Transitioning towards Net-Zero Emissions in Chemical and Process Industries: A Holistic Perspective

Abstract

Given the urgency to combat climate change and ensure environmental sustainability, this review examines the transition to net-zero emissions in chemical and process industries. It addresses the core areas of carbon emissions reduction, efficient energy use, and sustainable practices. What is new, however, is that it focuses on cutting-edge technologies such as biomass utilization, biotechnology applications, and waste management strategies that are key drivers of this transition. In particular, the study addresses the unique challenges faced by industries such as cement manufacturing and highlights the need for innovative solutions to effectively reduce their carbon footprint. In particular, the role of hydrogen as a clean fuel is at the heart of revolutionizing the chemical and process sectors, pointing the way to cleaner and greener operations. In addition, the manuscript explores the immense importance of the European Green Deal and the Sustainable Development Goals (SDGs) for the chemical industry. These initiatives provide a clear roadmap and framework for advancing sustainability, driving innovation, and reducing the industry’s environmental impact, and are a notable contribution to the existing body of knowledge. Ultimately, alignment with the European Green Deal and the SDGs can bring numerous benefits to the chemical industry, increasing its competitiveness, promoting societal well-being, and supporting cross-sector collaboration to achieve shared sustainability goals. By highlighting the novelty of integrating cutting-edge technologies, addressing unique industrial challenges, and positioning global initiatives, this report offers valuable insights to guide the chemical and process industries on their transformative path to a sustainable future.

1. Introduction

The transition to net-zero emissions is a critical undertaking for the chemical and process industries, given their role in combating climate change and ensuring environmental sustainability. Member countries of the United Nations Framework Convention on Climate Change (UNFCCC) committed in the Paris Agreement to limit the global temperature increase to well below 2 °C above pre-industrial levels and to aim for a limit of 1.5 °C. However, without drastic reductions in global greenhouse gas (GHG) emissions, even the 2 °C target could be exceeded before 2050. Recent data suggest that the global mean temperature near the surface between 2012 and 2021 was already 1.11–1.14 °C warmer than before industrialization, making it the warmest decade since records began. In Europe in particular, land temperature rose even faster during the same period: 1.94–1.99 °C [1].

Projections indicate that the annual average temperature near the surface between 2023 and 2027 could be 1.1–1.8 °C higher than the 1850–1900 average [2]. The Intergovernmental Panel on Climate Change (IPCC) Special Report on 1.5 °C Warming predicts that the world could reach the 1.5 °C threshold sometime between 2030 and 2052 [3]. A 2021 projection using a different methodology narrowed this timeframe to the early 2030s, underscoring the urgency of reaching the peak of global greenhouse gas emissions before 2025.

Within the industrial landscape, global energy-related CO₂ emissions continue to rise, reaching a new peak of over 36.8 Gt (gigatons) in 2022, with a growth rate of 0.9%, or 321 Mt/a (megatons per year) [4]. Most of the emissions growth was from energy combustion, which increased by 423 Mt, while emissions from industrial processes decreased by 102 Mt.

The materials industry, which includes process industries such as pulp and paper, chemicals, bio-based solutions, mining and metals, and more, contributes to 27% of global CO₂ emissions, including energy-related emissions [5]. Certain sectors such as cement, iron and steel, chemicals, and oil refining contribute significantly and account for about 7%, 6%, 2.6%, and 2% of total global emissions, respectively [6]. Given the complexity and energy-intensive production of certain industries, the food and beverage industry (responsible for 36% of global emissions) and the textile industry (responsible for about 10% of global GHG emissions) are not covered in this report.

The findings underscore the urgent need for further efforts to reduce emissions and shift to sustainable practices in the chemical and process industries. While significant progress has already been made, it is critical to align the trajectory of industrial growth with global climate goals to pave the way to a more sustainable and environmentally friendly future. Achieving net-zero emissions and contributing to a greener world will require collective and innovative action across all sectors to ultimately preserve the planet for future generations.

2. Literature Review

The chemical industry holds a pivotal position in the global economy, generating numerous jobs and making significant contributions to the GDP. By prioritizing emissions reduction, this industry can achieve substantial growth, which is projected to reach 2.5 times current levels by 2050. It also has the potential to play a crucial role in facilitating the transition to net-zero emissions across other sectors. Aligning with the Paris Climate Agreement, the chemical industry can effectively manage its own greenhouse gas emissions (Scope 1–3) while pursuing remarkable growth [7]. To realize these advantages, the European Commission has outlined a transition pathway specifically tailored to the chemical industry [8].

To explore the relevance of research in approaching net-zero emissions in the chemical and process industries, a literature search was conducted in Web of Science, Science Direct, and Google Scholar for the following keywords: ‘Chemical Industry’, ‘Chemical Industries’, ‘Process Industry’, ‘Process Industries’, ‘Net Zero’, ‘Net-Zero’, and ‘Emissions’. The period under consideration ranged from 2013 to half of the year 2023. The queries are listed in

Table 1. Search queries.

Keyword	Keyword No.	Query A	Query B	Query C
Chemical Industry	1	$\begin{array}{c}\left(1\vee 2\right)\\ \wedge \\ \left(5\vee 6\right)\\ \wedge \\ 7\end{array}$	$\begin{array}{c}\left(3\vee 4\right)\\ \wedge \\ \left(5\vee 6\right)\\ \wedge \\ 7\end{array}$	$\begin{array}{c}\left(1\vee 2\right)\wedge \left(3\vee 4\right)\\ \wedge \\ \left(5\vee 6\right)\\ \wedge \\ 7\end{array}$
Chemical Industries	2
Process Industry	3
Process Industries	4
Net Zero	5
Net Zero	6
Emissions	7

$\mathrm{Logical}\mathrm{operators}:\wedge -\mathrm{AND};\vee -\mathrm{OR};$.

. According to Google Scholar results, about 5670 articles on net-zero emissions have been published in the last ten years, of which about 75% were published in the last three years. In contrast, searches on Web of Science and Science Direct yielded a total of only 39 and 12 articles, respectively. The search results shown in Figure 1 clearly indicate that the urgency of addressing global climate change challenges has led the scientific community and the chemical industry to work together to develop sustainable solutions over the past decade. Although it is sometimes difficult to judge whether an article is aimed at a solution to reduce emissions or whether “net zero” is just being used as a buzzword, it is safe to say that awareness of the need for such solutions is deeply rooted in both academia and industry.

Having established the significance of research and the growing awareness of net-zero emissions in the chemical and process industries, we now turn to innovative approaches and transformative actions. These integrate principles of the circular economy and climate action, essential for a sustainable and low-carbon future [7]. Urgently limiting anthropogenic CO₂ release to levels absorbable by natural sinks becomes imperative [9]. Critical processes such as hydrogen production, ammonia synthesis, CO₂ reduction, and novel aspects of acetylene chemistry are vital for creating a sustainable chemical sector [10]. Innovative approaches play a crucial role in waste reduction and the discovery of new utilization methods [11]. A notable example is the direct incineration of brewer’s grains and coffee grounds, effectively removing biomass waste from urban solid waste streams, which is a commendable waste recovery method [12]. Another example is the addition of calcined canal sediments, otherwise considered waste, as an artificial pozzolanic material, which can improve strength and significantly reduce energy consumption and greenhouse gas emissions [13].

In addition to developing innovative technologies, the chemical industry needs a comprehensive and coordinated strategy that incorporates its interconnected supply chains to effectively achieve the goal of net-zero GHG emissions [14]. Even what was considered innovation some time ago must keep pace with a new paradigm. For example, conducting a thorough life cycle assessment (LCA) prior to establishing a biorefinery and its entire supply chain is essential to comprehensively assess environmental impacts [15]. Recently, circular design strategies, including the design-for-disassembly (DfD), have been promoted to address waste production, raw material consumption, and lack of reuse; however, their environmental impacts are not always measured [16]. Digital transformation is also important for decarbonization. Several computer-based tools facilitate design and allow more rapid assessment of the environmental impacts of chemical processes [17], as traditional LCA can take weeks to complete. One prominent avenue is the use of artificial intelligence (AI) as a valuable tool for mitigating CO₂ emissions in the chemical industry [18]. It is possible to integrate AI data and methods to estimate sustainability metrics and design for more sustainable chemical processes [19]. One example is the development of a sustainable closed-loop supply chain (SCLSC) incorporating a non-dominated sorting genetic algorithm that considers multiple subsystems and enables the optimization of concrete production to reduce carbon intensity while considering the complexity of customers, suppliers, production, and recycling stations [20]. In contrast to large-scale management systems, new technologies such as lab-on-a-chip are becoming increasingly popular [21].Computer-assisted engineering approaches are also important for integrating and optimizing existing processes with the aim of reducing emissions, as shown for example in the oxidative dehydrogenation of propane using CO₂ (CO₂-ODP) [22,23], a coal gasification system integrating a commercially available coal gasifier with the Allam Cycle [24], or optimizing carbon and energy flows in ethylene production [25].

System engineering approaches are relevant to the chemical and process industries, as well as to individual sectors with specific characteristics. The production of cement is a significant contributor to global CO₂ emissions, accounting for more than 7% of the total which can be reduced in many ways. Firstly, carbon emissions in Ordinary Portland Cement (OPC) can be brought down with the use of alkali-activated materials (AAM), which are traditional binders [26]. Secondly, the proposed option for reducing CO₂ emissions in the cement industry is the use of CO₂-containing flue gas and cement kiln dust (CKD) for producing mineral carbonates that serve as non-reactive fillers for blending cement [27]. Thirdly, the use of alternative supplementary cementitious material (SCM), such as biochar, obtained by pyrolyzing rice husks at a temperature of 550 °C, can be performed [28].

In addition to concrete production, the manufacturing of zeolites calls for more sustainable production due to a high energy consumption and substantial CO₂ footprint [29]. Similarly, achieving the production of high-quality iron at low temperatures is preferred [30].

Steel production is responsible for another 7% of CO₂ emissions globally and for 5% of emissions in the EU, which is why the EU steel industry is moving forward with hydrogen-based steelmaking as a decarbonization strategy [31].

All of the above-mentioned process industries are large consumers of energy; thus, developing renewable energy sources is crucial to get rid of coal-fired power plants (CFPPs), which cause significant harm to human health, the environment, and climate change [32]. The industry of synthetic ammonia is the largest energy consumer and CO₂ emitter in China’s chemical industry, and the process was reviewed from the viewpoint of deep emission reduction in terms of energy-saving and emission reduction potential [33]. However, the portfolio of low-carbon energy sources also includes hybrid energy systems (HESs) that provide heat and electricity to industrial processes [34].

In the effort to achieve net-zero greenhouse gas emissions, the use of CO₂ as a feedstock plays an important role [35,36]. Carbon capture and storage (CCS route, [37]) can be conducted with various mechanisms such as pre-combustion, post-combustion, oxy-fuel technologies, direct air capture, chemical looping combustion and gasification, ionic liquids, biological CO₂ fixation, and geological CO₂ capture [38]. Furthermore, the utilization of CO₂ in value-added chemical products through the electrochemical reduction method has attracted much attention [39], along with the improvement of existing process intensification technologies for CO₂ capture applications [40].

The sequestration and reduction of CO₂ require the development of a portfolio of technologies [41]. In addition, the integration of various renewable energy sources with CO₂ capture processes [42] and carbon-neutral processes to replace current industrial processes is urgently needed. Studies have been conducted on the sustainable synthesis of ammonia and iron with high value nanocarbon products by electrolysis in molten salt(s) with the introduction of the Solar Thermal Electrochemical Process (STEP) [41]. There is also potential for closing the carbon cycle (C-3) for the nation’s carbon-intensive industries, such as the production of olefins by reducing lignite for power generation in Germany and the need to increase carbonaceous waste recycling [43].

There is a critical need to further develop cost-effective technologies related to the use of CO₂ as a feedstock, valuable chemical, and material for fuels [41]. A carbon-neutral fuel is characterized by the utilization of the atmosphere as the primary source of hydrocarbons, followed by combustion that releases CO₂ as a byproduct [44]. In the area of thermo-catalytic CO₂ conversions to clean fuels, the core-shell catalysts for thermo-catalytic CO₂ conversion to syngas and fuels have recently received much attention [45]. The U.S. Department of Energy (DOE) aims to reduce the cost of clean hydrogen to 1 USD/kg in one decade [46].

In conclusion, addressing the challenges of climate change and creating a sustainable future for the chemical industry requires a comprehensive and coordinated approach. Integrating innovative technologies such as carbon capture and utilization, renewable energy sources, and process optimization is critical to reducing greenhouse gas emissions and minimizing environmental impact. In addition, accelerating digital transformation, applying circular economy principles, and conducting life cycle assessments can guide decision making toward more sustainable practices. To achieve a low-carbon and environmentally sustainable chemical industry, further research, collaboration, and policy support are essential.

3. Methods

A literature review, foreseeing the engineering developments from international organizations along with their analyses and syntheses, and personal experience were used as the methodology. The ChatGPT response was used in the literature overview analysis [47].

4. Results

This section reviews the current situation and methods planned for the net-zero transition. It is divided into sectors of process industries.

Net zero means cutting greenhouse gas emissions to as close to zero as possible, with any remaining emissions re-absorbed from the atmosphere by oceans and forests, for instance. The United Nations has organized a growing coalition of countries, cities, businesses, and other institutions that are pledging to work towards net-zero emissions [48]. More than 70 countries, including the biggest polluters—China, the United States, and the European Union—have set a net-zero target, covering about 76% of global emissions. More than 3000 businesses and financial institutions are working with the Science-Based Targets Initiative to reduce their emissions in line with climate science. More than 1000 cities, over 1000 educational institutions, and over 400 financial institutions have joined the Race to Zero, pledging to take rigorous, immediate action to halve global emissions by 2030.

4.1. Sustainable Development Goals

The 17 SDGs with 169 targets are the main action plan of the Paris Agreement [49]. The chemical and process industries play an essential role in achieving the SDGs by addressing environmental, social, and economic challenges and making an important contribution to the global economy by providing critical products and services to various industries. The pursuit of the SDGs is consistent with promoting clean production methods, optimizing resource efficiency, and minimizing environmental impact. Industry efforts to reduce GHG emissions and adopt CCUS techniques are an essential part of global climate action. In addition to environmental aspects, the chemical and process industries also impact the social and economic dimensions of sustainable development. By promoting innovation in materials science, process engineering, and sustainable technologies, the chemical process industry contributes to inclusive economic growth and job creation.

The World Business Council for Sustainable Development (WBCSD) has coordinated an SDG roadmap for the chemical sector proposed by leading chemical companies and industry associations [50]. Ten goals were identified as a priority of the sector: 2—Zero hunger, 3—Good health and well-being, 6—Clean water and sanitation, 7—Affordable and clean energy, 8—Decent work and economic growth, 9—Industry, innovation, and infrastructure, 11—Sustainable cities and communities, 12—Responsible consumption and production, 13—Climate action, and 14—Life below water. The roadmap outlines 18 impact opportunities that can contribute to the 10 priority SDGs. They are grouped into five key themes: food, water, people and health, energy, infrastructure, and cities. To reach the goals by 2030, innovation will be needed across products and processes, in cooperation with partners.

The International Council of Chemical Associations (ICCA) published six themes cross-referenced to specific SDG indicators: health and well-being; sustainable consumption and production; energy, environment, and sustainable cities; sustainable economies; learning and education; and public-private partnerships [51]. The article presented some other links to several trade associations, and examples of several chemical companies’ approaches.

American Chemical Society (ACS) has identified seven priority SDGs and five additional SDGs that are foundational to the work of the chemistry community [52]. The ACS Green Chemistry Institute organized various principles of green chemistry and engineering and presented them in three groups: (1) maximize resource efficiency; (2) eliminate and minimize hazards and pollution; (3) design systems holistically and using life cycle thinking—requiring chemists and chemical engineers to design, measure, be efficient, and be sustainable [53]. The European Chemical Industry Council (CEFIC) published a report focusing on four areas of impact: the low-carbon economy, resource efficiency, the circular economy, and for people and the planet [54].

Concrete and other materials based on cement are the most widely used construction materials due to their ease of use, flexibility, durability, and low cost [55]. Sustainable Development Report 2023 mentions cement only in connection with SDG 13-CO₂ emissions from fossil fuel combustion [56]. The high-volume fraction of annual CO₂ emissions (7–8%) is due to the large mass of cement-based materials produced—around 30 Gt/a [57]. Moreover, the cement industry has lowered specific emissions of CO₂ per mass of cementitious material by 19.2% since 1990 [58]. They knew this was not enough, and the GCCA committed to supporting its members in achieving carbon-neutral concrete by 2050. They are also significantly reducing emissions of airborne pollutants, such as dust and NO_X, that directly impact human health [57]. Alternative fuels are a key area in which the cement industry can significantly contribute to the wider communities in which it operates, as a sustainable solution to waste management. The use of refuse-derived fuels (RDF) has reached substitution rates well over 50% in Europe, and companies are pushing them to hit 100%. Cement will be a critical resource in achieving many SDGs.

UN have declared 2022 the »International Year of Glass« (IYOG) to raise awareness of the significant contribution this material has made over several millennia of human history, and the important role it will continue to play in the future. In the description of glass achievements, they mentioned that “Glass melting is being de-carbonized and glassy products are being safely recycled)” [59]. The aim of the IYOG was to highlight the important role of the glass in achieving the 17 SDGs [60]. The most important goals will be SDG 3 (bioactive glasses), 6 (porous and coated glass filters), 7 (covers and reflective mirrors for photovoltaic systems, glass photobioreactors, glass-reinforced composite materials for wind turbines), 9 (optical fibers, doped glass, ultra-thin glasses, spherical lenses, prisms, and beam splitters), 11 (chemically reinforced glass and coated windowpanes), and 12 (high recycling rates, energy-efficient melting technologies, and optimized glass compositions).

Intensity of association between 10 metal (steel, copper, aluminum, nickel, zinc, gold, silver, platinum group metals, silicon, and rare-earth elements) producing companies, estimated from their corporate social responsibility (CSR) reports, sustainability reports, and integrated reports, was the largest with the SDG 8, followed by SDG 3, SDG 12, and SDG 9 [61]. The metals industry review with 152 metal companies places the most focus on SDGs 8, 3, and 12, but its activities are less associated with SDGs 14, 2, and 1 [62]. The steel sector is the most important sector in the European process industry. The steel industry places great weight on SDG 12 and less on SDGs 1 and 2, whereas the copper industry recognizes the relevance to SDGs 1 and 2.

Worldsteel is focusing on climate action, responsible value chain, life cycle thinking, circular economy, water management, and air quality [63]. In the area of climate action, e.g., they are proposing three groups of policy goals and development initiatives:

• Breakthrough technologies: (a) Using carbon as a reductant while preventing the emission of fossil CO₂, for example using CCUS and/or sustainable biomass, e.g., bio-charcoal; (b) Using electricity through an electrolysis-based process; (c) Substituting hydrogen for carbon as a reducing agent, generating H₂O instead of CO₂.
• Efficiency and circular economy: (a) Optimal raw material selection and use, (b) Increasing energy efficiency and minimizing waste, (c) Improving yield, (d) Improving process reliability, and (e) Circular economy with four Rs: Reduce, Reuse, Remanufacture, and Recycle.
• Developing advanced steel products to enable societal transformations: (a) Developing and manufacturing the advanced steel products necessary to facilitate the required transformation and adaptation of society and reach carbon neutrality through zero-energy buildings, renewable energy infrastructures, electrification, etc. (b) Assisting customers in delivering innovative solutions using steel and introducing new, advanced steel products.

Environmental standards, e.g., ISO 14000 series on Environmental Management Systems, Environmental Auditing, Environmental Labeling, Environmental performance, Life Cycle Assessment, etc. [64], ISO 26000 on social responsibility [65], and EU Eco-labeling system, e.g., Environmental Product Declaration (EPD) [66] are upholding their importance.

The pulp and paper industry must align its sustainability strategy with the SDGs as well. In Canada, Resolute Forest Products, committing to ESG principles, identified eight SDGs that align with its sustainability strategy [67]: SDG 6 (Water management), SDG 7 (Energy), SDG 8 (Employees’ health, safety and wellness), SDG 9 (Economic performance and infrastructure investments), SDG 12 (Waste management), SDG 13 (Climate change), SDG 15 (Forest management, fiber sourcing practices, and biodiversity), and SDG 16 (Environmental compliance). In 2021, they surpassed their 2025 GHG emission reduction target ahead of schedule, and in 2022, the Science-Based Targets initiative (SBTi) validated their new reduction goals, which include the 41.5% reduction in absolute scope 1 and 2 emissions by 2026 from a 2015 base year, and a 16.5% reduction in scope 3 emissions within the same timeframe [68]. Over the past two decades, their carbon-reduction initiatives have cut more than 7.3 Mt/a of GHG, comparable to taking close to 1.6 million cars off the road.

Asia Pulp & Paper (AP&P) prepared a new Sustainability Roadmap Vision 2030 guiding them in fulfilling their commitment to protect forests, support communities, conserve biodiversity and work towards achieving carbon neutrality across their operations [69]. The earlier Vision 2020 set out ten key impact areas relevant to stakeholders across their business and wider supply chain: climate change, emissions, solid waste, reforestation, conservation and biodiversity, human rights and indigenous people, community empowerment, employee welfare, fiber sourcing, and water management. AP&P have met most of the targets set out in the Sustainability Roadmap Vision 2020, e.g., protection and restoration of national forest, 40% fiber was from recycled sources, carbon intensity decreased 29% compared to a 2012 baseline, energy intensity decreased 14%, water intensity decreased 30%, and solid waste reduction was 47%, etc. Vision 2030 focuses on three main areas:

• Production—30% reduction of carbon footprint by (a) increased share of renewables in the energy mix, (b) reduced energy consumption, (c) reduced water consumption, (d) zero waste to landfill, (e) increase recycled fiber composition, and (f) increased product biodegradability and resource efficiency.
• Forest—over 0.5 Mha of natural forests area conserved by (a) sustainable forest management, protection, and restoration (of APP property and supplier concessions), (b) increased fiber productivity. (c) Protecting and conserving the forests, peatlands and biodiversity that sustain their business; (d) maintain the area impacted by fires at under 2%.
• People (improving the lives of millions) by (a) reduction of land conversion for agricultural purposes through the use of fire, (b) improve the welfare of local communities through capacity building and enhance community access to markets, (c) respect the rights of local communities and indigenous people thorough increased multistakeholder engagement, (d) increase the number of women in management positions, (e) strengthen organizational agility, (f) best practices for fraud reporting and whistleblower management, and (g) best practices for ensuring adherence to their Code of Conduct.

4.2. European Green Deal

EGD plans to transform the EU into a modern, resource-efficient, and competitive economy, ensuring: (1) no net emissions of greenhouse gases by 2050 (at least 55% reduction by 2030), (2) economic growth decoupled from resource use, and (3) no person and no place left behind [70]. The European Green Deal shall improve the well-being and health of citizens and future generations by providing: (1) fresh air, clean water, healthy soil, and biodiversity; (2) renovated, energy-efficient buildings; (3) healthy and affordable food; (4) more public transport; (5) cleaner energy and cutting-edge clean technological innovation; (6) longer lasting products that can be repaired, recycled, and re-used; (7) future-proof jobs and skills training for the transition; (8) a globally competitive and resilient industry. In 2023, the Commission presented an EGD Industrial Plan to enhance the competitiveness of Europe’s net-zero industry and support the fast transition to climate neutrality [71]. It is based on four pillars: (1) a predictable and simplified regulatory environment, (2) speeding up the access to finance, (3) enhancing skills, and (4) open trade for resilient supply chains.

CEFIC sees the transformation to a climate-neutral and circular economy as a key driver of European jobs and economic growth [72]. The European chemical industry has the ambition to become climate neutral by 2050. To reach it, decarbonized and circular economy solutions shall be developed by the chemical industry. Access to abundant and competitive low-carbon energy, development of relevant infrastructure, as well as new market opportunities related to sustainable products, are key conditions to ensure that the industry stays globally competitive during the transition [73]. Costs and opportunities of the EGD for the chemical industry for core equipment and the design, construction and modification of facilities have been estimated to be 400–600 GEUR by Accenture [74]. Chemicals for the EGD are foreseen to be used in (1) Renewable energy, (2) Clean Road transport, (3) Circular economy, (4) Public health, (5) Electronics, (6) Aerospace, etc.. The chemical industry is indispensable to Europe’s strong and sustainable economy of the future, as chemicals are present in almost every strategic value chain [75].

Other sectors of process industries have also been active. The European Cement Association Cembureau published the Carbon neutrality roadmap to demonstrate that reaching net-zero emissions along the cement and concrete value chain is achievable by 2050 in key areas: (1) CCUS (42% of the CO₂ emissions reduction), (2) Replacement of fossil fuels by non-recyclable and biomass waste (15% of the emissions reduction), and (3) Providing low carbon-cements products (13% emissions reduction), etc. [76].

The EU is the world’s biggest glass producer, with a market share of around one-third of the total world production. Glass production in the EU reached 36.8 Mt in 2020 according to Glass Alliance Europe. It comprises five subsectors: 60.4%—Container glass, 29.2%—Flat glass, 3.2%—Domestic glass, 5.3%—Fibers (reinforcement and insulation), and 2.1%—Special glass [77].

The pulp and paper industry (P&PI) is the fourth most energy-intensive industry in Europe. Since 2005, CO₂ emissions of the pulp and paper sector have been reduced by 36%. By substituting fossil-based products, the European forest-based industries lowered the EU’s total emissions by an estimated 410 Mt/a [78]. P&PI is the largest industrial generator and user of renewable energy—60% of the industry’s total primary annual energy consumption is biomass-based [79]. In 2019, European P&PI chief executive officers (CEOs) declared their intention to be at the forefront of supporting the 2050 carbon-neutral society. In 2020, Cepi 2030 Industry Manifesto responded to the tightening climate change policy in the EU. Their future is also tackling fiber-based packaging circularity, biorefineries, emerging bio-based products (e.g., human-made cellulosic fibers), and a shift towards a low-carbon circular bioeconomy.

In 2024, the EU Corporate Sustainability Reporting Directive (CSRD) will strengthen the rules concerning the environmental, social, and governance (ESG) information that large companies with more than 250 employees and 40 MEUR in net turnover or 20 MEUR in assets [80], and listed companies must report [81]. The CSRD is expected to increase the number of companies subject to the EU sustainability, as they reported requirements from 11,700 to approximately 50,000. They will have to report according to the European Sustainability Reporting Standards (ESRS) and will require external auditing.

The EU has accepted a Green Deal Industrial Plan to enhance the competitiveness of Europe’s net-zero industry and support the fast transition to climate neutrality. It is based on four pillars: (1) a predictable and simplified regulatory environment, (2) speeding up access to finance, (3) enhancing skills, and (4) opening trade for resilient supply chains [82]. The European Commission published the Transition pathway for the chemical industry [83], identifying electrification, hydrogen, biomass, waste, Carbon Capture and Utilization (CCU), Carbon Capture and Storage (CCS), and process efficiency as key technological contributors to the transition pathway.

Bengtsson et al. have studied more than 20 decarbonization projects in the chemical industry in 9 developed EU member states [84]. Their CO₂ emissions could be reduced by pursuing steam generation, utilizing residual heat, changing electricity procurement, and improving energy efficiency. Industrial clusters, also known as “chemical parks”, could reduce their CO₂ emissions by 50–60% until 2030 in the fields of steam generation (25–30%), heat integration (10–15%), electricity procurement (10–15%), and energy efficiency (1–3%). In steam generation, coal can be substituted by seven carbon-free heat-source technologies—biomass, solar thermal, hydrogen, biogas, thermal storage, heat pumps, and e-boilers.

4.3. The Role of Chemical Process Systems’ Engineering

The vision for the chemical industry to achieve net-zero emissions by 2050 exists. The Center for Global Commons at the Tokyo University & Systemiq, for example, identified three main strategies: replacing fossil fuels with alternative feedstocks, switching from fossil to renewable energy sources, carbon capture, storage, and utilization [7]. It highlights the main chemicals, namely green hydrogen, ammonia, methanol, olefins, and aromatics, whose synthesis needs to be switched from fossil to non-fossil feedstocks, specifically hydrogen from the electrolysis of water, nitrogen from the air, and carbon from biomass, waste, and/or captured CO₂. Also listed are seven major production processes for the carbon-free production of primary chemicals: (i) electrolysis of water to produce green hydrogen, (ii) reforming of methane, (iii) gasification of biomass and waste to produce syngas followed by methanol and ethanol synthesis, (iv) CO₂ capture and conversion to methanol with green hydrogen, (v) steam cracking of biomass and waste to produce olefins and aromatics, (vi) catalyzed conversion of methanol to downstream chemicals (methanol to X), and (vii) dehydration of ethanol to olefins. Since all these processes are very energy intensive, it is important that they use renewable energy to get to a net zero. The report states that in a certain scenario, it would even be possible for the global chemical industry to become carbon-negative before 2050 by acting as a CO₂ sink and generating economic value from it.

While the vision and strategies for a net-zero chemical industry are well defined, the concrete pathways to achieve these goals are less obvious. The introduction of the above principles will enormously increase the demand for hydrogen, ammonia, and methanol. Therefore, consumption must also decrease, and this requires a much higher level of circularity than today, when the global circularity level is only 7.2% in 2023 [85]. Does society have the knowledge, motivation, and resources? Are the know-how and skilled professionals available to design net-zero transition technologies? Over the decades, chemical process systems engineering has developed a remarkable methodological portfolio of methods and tools for process design and optimization that are key to achieving net-zero transition, such as efficiency improvement, multi-objective optimization, process integration, and process intensification.

Increasing efficiency. To reduce resource consumption, the efficiency of bio-based chemical processes must be increased. The conversion of renewable and alternative resources, e.g., biomass and waste, is often less efficient economically and technologically than the conversion of fossil resources [86]. There is a need to encourage investment in low-carbon technologies and carbon capture and storage/utilization through various financial incentives [87]. On the other hand, fossil-based technologies are still economically attractive in many cases and should be charged accordingly for CO₂ emissions. A higher CO₂ tax in process optimization promotes higher reactant conversion, lowers feedstock consumption, and increases the required investment by encouraging the use of more efficient process units and higher quality feedstocks [88].

Multi-Objective Process Optimization. The introduction of technologies to move the chemical industry closer to net-zero production involves many conflicting criteria. Reductions in greenhouse gas emissions are usually associated with reductions in economic benefits [89]. It was shown by Kasaš et al. that trade-off solutions between economic, operational, and environmental criteria can be achieved if an appropriate objective function is used [90]. This is usually the net present value that promotes a balance between the return on invested funds and the long-term generation of a stable cash flow with moderate environmental impacts and operational efficiency.

Process Integration. Process integration is one of the main methodological approaches that contributes significantly to the decarbonization of the chemical industry [84]. It leads to a lower consumption of heat, energy, and materials, and thus lower emissions [91]. The use of process integration is expanding to include greenhouse gas emissions’ planning and reduction [92]. It is a mature approach that includes various methods such as pinch analysis, mathematical programming, and P-graphs [93]. The most common applications are the integration of hot and cold streams within the process and in total sites which offer the possibility of using the excess process heat in residential areas [94]. With the use of heat pumps, it is possible to recycle even low-temperature waste heat and increase the efficiency of the generated heat and electricity from renewable sources by coupling a heat pump with a CHP unit [95].

4.4. Process Industries

The chemical sector is the largest industrial energy consumer and the third largest industry subsector in terms of direct CO₂ emissions [96]. This is largely because around half of the chemical subsector’s energy input is consumed as feedstock—fuel used as a raw material input rather than a source of energy. In 2021, direct CO₂ emissions from primary chemical production reached a total of 925 Mt [97]. In the Net-Zero Emissions by 2050 Scenario, CO₂ emissions will be reduced by 17% until 2030—both the private and public sectors will need to achieve technological innovation, efficiency gains and higher recycling rates. Ammonia production is responsible for the highest fraction of emissions, followed by high-value chemicals (i.e., ethylene, propylene, benzene, toluene, and mixed xylenes) and methanol.

4.4.1. Chemical Industry

Direct CO₂ emissions from primary chemical production reached 925 Mt in 2021 [97]. This represents a 5% increase from the previous year, due to higher production levels than in 2019 [4]. However, the CO₂ intensity of primary chemicals has remained relatively stable at around 1.3, indicating the mass ratio of emitted CO₂ to primary chemicals produced. On a global level, the chemical industry is responsible for about 4% of global greenhouse gas emissions.

On a more positive note, the chemical industry in the EU has made remarkable progress in reducing its environmental impact. Despite an increase in the production of more than 43% since 1990, greenhouse gas emissions from chemical production in the EU-27 have decreased by 55% compared to 1990 [98]. Over the same period, energy consumption in the EU-27 chemical industry has fallen by 22%, and chemical waste has decreased by nearly a third since 2007. In addition, the introduction of industrial biotechnology products promises to further reduce greenhouse gas emissions while maintaining product performance [98].

Industrial chemicals, such as ammonia, methanol, and ethylene, are crucial feedstocks for over a dozen different sectors—from healthcare, agriculture, and construction, to packaging, cars, and textiles [99]. However, the chemical industry is also deeply involved in many issues related to Planetary Boundaries, such as greenhouse gas emissions, the discharge of waste plastics into the oceans, deviations from the natural cycle of nitrogen and phosphorus, and the loss of biodiversity [7].

The chemical industry plays a significant role in global emissions due to its energy-intensive processes and reliance on fossil fuels. However, several promising and state-of-the-art technological innovations are emerging to shift the industry towards net-zero emissions.

Carbon Capture, Utilization, and Storage (CCUS) [100,101]. CCUSs capture CO₂ emissions from industrial processes and either store CO₂ underground by injecting it into suitable geological formations or utilize it for other purposes [102]. Technologies such as electrochemical conversion [103,104], catalytic hydrogenation [105], and photocatalytic conversion of CO₂ [106] have the potential to reintegrate captured CO₂ into the value chain by converting it into fuels and chemicals.

Electrification and renewable energy integration. Shifting from fossil fuel-based energy sources to renewable energy is crucial for decarbonizing the chemical industry. The electrification of processes [107,108], by switching from fossil-powered processes to electricity-powered processes (e.g., electrical furnaces and boilers, heat pumps) and the integration of renewable energy sources [109,110,111,112], such as solar, wind and biomass, can reduce or eliminate the need for fossil fuel combustion.

Hydrogen as a feedstock and energy carrier. Hydrogen produced from renewable sources (green hydrogen) can serve as a clean feedstock and energy carrier in chemical manufacturing processes. It can be produced by biological processes [113,114], e.g., direct, and indirect photolysis, photo-fermentation, or dark fermentation), by thermochemical processes [115], e.g., biomass pyrolysis and gasification, or electrolysis of water [116], by electrolysis, e.g., proton exchange membrane electrolysis, anion exchange membrane electrolysis [117], or solid oxide electrolysis [118].

Bio-based feedstocks. The utilization of bio-based feedstocks derived from biomass can help reduce the industry’s reliance on fossil fuels. Biomass, such as agricultural residues [119], and food wastes [120], can be converted into bio-based chemicals through various processes such as fermentation [121], enzymatic conversion [122], or thermochemical conversion [123].

Process optimization and advanced catalysts. Improving the efficiency of chemical processes and developing advanced catalysts [124,125], can reduce energy consumption and emissions through increased conversion and selectivity and milder operating conditions with respect to temperature and pressure. Optimization techniques, for example process intensification [126,127] and heat integration [128], enhance the overall energy efficiency and sustainability of chemical production.

Circular economy and recycling. Embracing a circular economy approach within the chemical industry involves designing products for reusability, recycling, or biodegradability [129]. Developing innovative recycling technologies, such as chemical recycling, enables the recovery of valuable materials and reduces the need for virgin feedstocks [130].

Artificial intelligence (AI) and data analytics. AI and data analytics can be employed to optimize processes [131], predict and detect anomalies [132], etc. AI and data analytics will play a major role in boosting new product development, increasing the safety and reliability of chemical production processes, and enhancing the sustainability of chemical supply networks.

4.4.2. Pharmaceutical Industry

The pharmaceutical industry plays a vital role in advancing human health, but its environmental impact cannot be overlooked. The manufacturing processes involved in pharmaceutical production generate significant GHG emissions [133], contributing to climate change. The pharmaceutical industry is responsible for an estimated annual direct emission of approximately 52 Mt of CO₂ equivalent worldwide [134]. It is important to note that this estimation solely accounts for emissions directly generated by pharmaceutical activities, without taking into consideration the indirect emissions associated with energy use throughout the entire supply chain. Indirect emissions may arise from various sources such as the transportation of medicines, lighting and refrigeration in distribution facilities, and other energy-related processes.

The pharmaceutical industry is exploring various state-of-the-art technological innovations that hold promise for shifting towards net-zero emissions. Several key advancements have emerged in recent years:

Green Chemistry and Sustainable Synthesis. The adoption of green chemistry principles and sustainable synthesis methods is gaining traction in pharmaceutical manufacturing. This approach focuses on minimizing the use of hazardous materials [135], optimizing chemical processes, and designing more environmentally friendly reactions to reduce waste generation and energy consumption [136,137].

Process Intensification and Continuous Manufacturing. Process intensification involves optimizing manufacturing processes to improve efficiency, reduce resource consumption, and decrease emissions. Continuous manufacturing, as opposed to batch processing, allows for streamlined operations, reduced waste, and improved energy and material efficiency, thereby lowering the overall carbon footprint [138,139,140,141].

Decentralized Energy Generation and Advanced Energy Management Systems. Utilizing waste-to-energy systems [142], solar photovoltaic systems, wind turbines, and biomass energy facilities on-site can significantly reduce reliance on fossil fuels. Advanced energy management systems integrate energy storage, demand response, and smart grid technologies. This enables the optimization of energy use, real-time monitoring of energy consumption, and identification of opportunities to improve energy efficiency.

Circular Economy and Waste Reduction. Implementing circular economy practices within the pharmaceutical industry can minimize waste generation and resource depletion [143,144]. Recycling and repurposing of materials [145], implementing closed-loop systems [146], and developing innovative recycling technologies [147] enable the recovery of valuable resources, reducing the reliance on virgin materials and reducing emissions associated with raw material extraction and production.

Digitalization and Data Analytics. Leveraging digital technologies, such as artificial intelligence (AI), machine learning, and data analytics [148,149], can identify novel and sustainable reaction pathways and thus directly or indirectly optimize processes, improve energy efficiency, and identify opportunities for emission reduction. Advanced modeling and simulation tools [150] can also aid in designing more sustainable and environmentally friendly pharmaceutical manufacturing processes [151,152].

It is important to note that while these technological innovations hold significant promise, their widespread adoption requires collaboration between industry stakeholders, policymakers, and research institutions. Continued research, development, and investment in these areas are crucial for achieving the pharmaceutical industry’s goal of net-zero emissions and contributing to global sustainability efforts.

4.4.3. Cement Industry

Around 40% of CO₂ emissions from fuel combustion worldwide and 25% of global GHG emissions are attributed to the built environment [153]. Among these figures, cement production stands out as one of the most significant contributors, responsible for 6–10% of global CO₂ emissions [154]. Achieving net-zero emissions by 2050 will necessitate the swift decarbonization of the cement and concrete sector.

The cement and concrete industry can utilize the following strategies to accomplish their decarbonization objectives.

Reducing the fraction of clinker in cement. The emission from cement production is predominantly caused by clinker, accounting for roughly 90% of the total [155]. This makes it imperative for industry stakeholders to prioritize finding solutions for clinker-related emissions. To decarbonize the industry, cement manufacturers can explore the possibility of replacing clinker with alternative materials such as fly ash [156,157], granulated blast furnace slag [158], calcined clays [159] and even red mud, to some extent [160,161].

Reducing energy-related CO₂ emissions. To decrease emissions associated with energy usage, industry participants are actively investigating alternative fuels (biomass and municipal and industrial wastes and their mixtures) [162,163], developing innovative technologies such as kiln electrification [164,165], oxy-combustion [166], and heat generation via plasma technology [167].

Carbon capture, storage, and utilization. The CO₂ emissions captured from production processes [168,169] can be reintegrated into the value chain through various means [170]. For instance, they can be utilized in the production of recycled clinker (mineralization, [171]) or incorporated into fresh concrete (carbon curing, [172]). Moreover, concrete structures can absorb a substantial amount of CO₂ during their lifespan through a process called recarbonation.

4.4.4. Glass Industry

In 2019, the world consumed more than 194 Mt/a of glass, and the demand is forecast to increase to 256 Mt/a by 2027 [173]. Glass is made in furnaces at extremely high temperatures (up to 1700 °C) to melt several minerals, including silica (the main ingredient, in the form of sand), soda ash, and limestone. Producing it causes 95 Mt/a of GHG emissions worldwide [174]. The EU has set a timetable for the reduction of GHG emissions, with a 30% reduction target from 1990 levels by 2030 and 40% by 2040, culminating in net zero by 2050. The main methods forecast are energy efficiency, renewable sources of energy, minerals’ selection and composition, and circular economy. Globally, fuel emissions (mass ratio of CO₂ and melted glass) were reduced by 69% between 1960 and 2010 [173].

The UK glass industry has increased energy efficiency by 50% in the last 40 years by using waste heat, Organic Rankine Cycle, or steam turbine to preheat raw materials, fuel, or oxidants [175]. Oxyfuel combustion is using oxygen instead of combustion air, yielding energy savings of 10–15% and reduced emissions. Fossil fuels can be replaced by biofuels with reduced emissions of NOx. All electric furnaces are an established technology in the glass sector and are more efficient than gas-fired furnaces. The latest development is using up to 80% electricity with 20% gas energy (hybrid furnaces) with the future opportunity to consider hydrogen combustion using 100% hydrogen as well as different proportions of hydrogen blended with natural gas for glass melting.

Process emissions can be reduced by using a higher fraction of recycled glass which substitutes the carbonate raw material and reduces CO₂ emissions [175]. Alternative raw materials, such as calcium oxide, mineral slags, waste incineration ashes, etc., can replace carbonate raw material or reduce the melting temperature of the glass and thereby energy requirements. CCUS may be needed as a final stage for decarbonization.

Recycled glass reduces the usage of raw materials and GHG emissions as well as air and water pollution. Saint-Gobain was the first manufacturer in the world to achieve zero carbon flat glass production using 100% recycled glass (cullet) and 100% green energy, produced from biogas and decarbonized electricity [176].

4.5. Biotechnology

Industrial biotechnology, based on renewable resources, can save energy and significantly reduce CO₂ emissions. Bio-based chemicals can replace their fossil-based counterparts with significant GHG emissions reductions [177]. Bio-based plastics are potentially attractive in terms of specific emissions and energy savings. Governmental intervention can play a significant role in the effort to advance the industrial biotechnology sector toward lower GHG emissions, e.g., emissions trading systems (ETS) or tax for transportation emissions, pollution costs charged to petrol-based materials, labeling systems for bio-based materials and biofuels, public procurement supporting bio-based materials and sustainably produced biofuels [178].

4.6. Metals Production

4.6.1. Iron and Steel

CO₂ emissions and energy use in European steel production have already been halved since 1960 [31]. Presently, the EU steel industry is mainly focusing on hydrogen-based steelmaking as a decarbonization strategy. Carbon capture and utilization technologies will be developed in partnership with the chemical industry. Recycled iron and steel waste, and the electrolytic reduction of iron ore will be used for iron and steel production. Renewable electricity and transmission networks, hydrogen-related infrastructure or CO₂ transport, and storage infrastructures will be built.

4.6.2. Aluminum

An aluminum net-zero transition strategy will require [179]:

• Power decarbonization is critical: all smelters will need to switch to low carbon power by 2035, equating to approx. 1000 TW h of low-carbon electricity demand.
• Power decarbonization is necessary but not sufficient to decarbonize the sector; new technology for low carbon anodes and new refining technologies need to be commercialized by 2030.
• Recycled aluminum plays a critical role, expanding from 33% of supply in 2020 to over 50% by 2050.
• Mobilizing approximately 1 TUSD (10¹² USD) of the investment over the next 30 years will be needed to deliver the transition for the primary aluminum sector, with over 70% of the sum required for supporting infrastructure, most of it for power supply.

4.7. Pulp and Paper

• The pulp and paper industry is among the top five most energy-intensive industries globally and is the fourth largest industrial energy user. This industry accounts for approximately 6% of global industrial energy use and 2% of direct industrial CO₂ emissions [180]. As the paper production will increase, greater efforts must be made to reduce the emissions intensity of production by 2030 by substituting fossil fuels with renewable energy sources, e.g., biofuels, accelerating the energy efficiency improvements, and reducing the energy needed for drying [181].
• Substituting more pulp by recycled wastepaper to over 60% by 2030.
• Installation of high-temperature heat pumps using waste heat sources inside the production process.
• On-site waste heat recovery and co-generation.
• Emerging technologies, e.g., heat recovery from thermomechanical pulping, black liqueur gasification, microwave drying, supercritical CO₂ or deep eutectic solvent.

EU believes that by 2050 the European pulp and paper industry can reduce its energy consumption by 14% and greenhouse gas (GHG) emissions by 62% compared to 2015 levels [182]. Carbon capture and storage (CCS) could further reduce GHG emissions. Biorefinery products from the pulp and paper mills could replace fossil fuels for light duty vehicles, be used as raw materials in the chemical industry, or as fertilizers.

4.8. Key Technologies Related to Net-Zero Emission

Several technologies, directions, and approaches have been identified as important for the transition to a net-zero economy. Some of these are tailored to a specific industry, such as the reduction of the fraction of clinker in cement in the cement industry, while others are across industries, such as carbon capture, electrification, waste reduction, etc. To indirectly assess the activity of the development and interest in respective fields as they pertain to net-zero emissions, a Google search was performed relating some of these to net-zero emissions. The results are shown in Figure 2.

As can be observed from the bar chart in Figure 2, most of the net-zero activities relate to hydrogen. This is followed by Recycling and Electrification, which are the second and the third most active areas linked to net-zero emissions. Just below the top of the list are Carbon Capture, Circular Economy, Artificial Intelligence, Data Analytics, Digitalization, and Waste Reduction. This representation is by no means conclusive, as it is merely a snapshot of current trends. In addition, it may possibly be skewed by the search algorithm. However, it potentially does reveal that to achieve net-zero emissions, several technological solutions must be developed further and eventually implemented in an integrated framework.

5. Conclusions and Outlook

The review highlights the important concept of achieving net-zero emissions as more than just a singular focus on energy production. While the decarbonization of energy production remains critical, it is imperative to extend this goal to the entire supply and value chain to achieve a sustainable and carbon-neutral future. The discussion highlighted that the advancement of renewable energy technologies is a key pillar in the pursuit of net-zero emissions. We would also like to shed light on the major challenge that fossil-based feedstocks pose to the chemical industry. Switching to sustainable and renewable feedstock sources is critical to reducing emissions associated with chemical production processes. The importance of a comprehensive systems approach to achieve net-zero emissions was highlighted.

Megatrends are presumptive transformations of a global society, economy, or ecosystem. The most often cited megatrends are climate change with environmental degradation and resource scarcity, growing consumption, acceleration of technological change and digitalization, economic shifts, demographic change, rapid urbanization, and social instability [183]. Three megatrends have been observed in the chemical industry [184]:

• Sustainability and the circular economy, e.g., bio-based plastics, battery material recycling, and improving the efficiency of wind turbines.
• Digitalization, e.g., artificial intelligence (AI) to drive efficiency, sensors, and the internet of things (IoT) to transform logistics, collaboration with tech giants key to remain ahead of the curve, and machined to perfection.
• Innovation and accelerated globalization, e.g., novel manufacturing process, making composites affordable, and advanced materials for better insulation.

Deloitte has published the following four trends for chemical industry [185]:

• Sustainability and innovation (integrating innovation and sustainability to move beyond abatement).
• Portfolio transformation (near-term portfolio action positions the industry for long-term transformation).
• Supply chains (rearchitecting to balance costs, carbon footprint, and resilience).
• Digital (emerging technologies drive value chain improvements and sustainability).

Four solutions for fuel switching (green hydrogen, electrification, turquoise hydrogen, and waste heat capture) will be ready in the next decade, but 11 solutions (carbon capture and utilization, industrial bio-based operations, steam cracker electrification, small modular nuclear reactor, and electrification) need further development to drive long-term impact.

Net-zero activities are addressing the climate and resource problems. Energy and resource efficiency, and simple circular economy are addressing the welcomed low hanging fruits. The European Commission has proposed the Net-Zero Industry Act (NZIA) to promote the production of clean technologies in the EU and prepare for the transition to clean energy [186]. It shall significantly contribute to decarbonization by developing batteries, biogas/biomethane, carbon capture, and sustainable and alternative fuel technologies. The proposal was not accepted by the industry—Cefic (European Chemical Industry Council), described it as a “Zero Industry Act” [187].

Achieving net-zero emissions in the chemical process industries necessitates a holistic approach that combines technological advancements, supplies chain considerations, and societal transformation. While challenges exist, the CPI sector has the potential to significantly contribute to global emission reduction efforts. Collaboration, innovation, and a transition towards sustainable lifestyles are crucial for turning net-zero emissions into a tangible reality.

Yet, transitioning towards zero emissions will not be possible unless significant changes in the way human society functions occur. De-growth in developed countries and slower growth in developing ones is needed. OECD published a framework to decarbonize the economy [188]. Key aspects include:

• Emission pricing policy instruments;
• Standards and regulations;
• Complementary policies to facilitate the reallocation of capital, labor, and innovation towards low-carbon activities and to offset the adverse distributional effects of reducing emissions.

In conclusion, recognizing the complex interlinkages between sectors and understanding that emissions need to be addressed holistically across the value chain are crucial aspects to successfully achieving this ambitious goal. Furthermore, the roadmap toward net-zero emissions must encompass not only net-zero energy production, but also net-zero feedstock production. By ensuring that raw materials are sustainably sourced and do not contribute to net emissions, we can significantly reduce the carbon impact of various industries. In this effort, we emphasize the importance of highly selective conversions and striving for high recycling rates of products and equipment. By optimizing processes and reducing waste, we can minimize emissions throughout the life cycle of products and contribute to a more sustainable economy. However, making the transition to net-zero emissions a reality requires concrete strategies, innovative approaches, and effective policies. Joint efforts by governments, businesses, and consumers will play a crucial role in bringing about meaningful change. The roadmap to achieving net-zero targets requires a comprehensive, collaborative, and multifaceted approach. By considering all aspects of the economy, from energy production to raw materials and the life cycle of products, we can effectively navigate the path towards a sustainable future for generations to come.