Search Results (12)

Plastic waste poses a significant challenge in Africa and around the world, with its volume continuing to increase at an alarming rate. In Africa, an estimated 25–33% of daily waste is made up of plastic, posing a threat to the environment, marine life, and human health. One potential solution to this problem is waste-to-energy recycling, such as pyrolysis, which involves the conversion of waste materials into oil, char, and non-condensable gasses through a thermochemical process in the absence of oxygen. Given the abundance of waste in Africa and the continent’s energy challenges, pyrolysis offers a sustainable solution. This review delves into the concept of pyrolysis, its products, thermodynamics, and endothermic kinetics, presenting it as a promising way to address the plastic waste problem in Africa. Despite the African Union’s goal to recycle plastic waste, the continent faces significant barriers in achieving this target, including infrastructural, economic, and social difficulties. It is crucial to implement sustainable strategies for managing plastic waste in Africa to mitigate environmental degradation and promote a cleaner and healthier living environment. Pyrolysis technology is highlighted as a viable solution for plastic waste management, as it can convert plastic waste into valuable byproducts such as oil, char, and syngas. Case studies from countries like South Africa and Nigeria demonstrate the potential for scaling up pyrolysis to address waste management issues while generating energy and job opportunities. This review underscores the need for investment, regulatory support, and public awareness to overcome the challenges and unlock the full potential of pyrolysis in Africa. Embracing pyrolysis as a method for managing plastic waste could lead to significant environmental and economic benefits for the continent. Full article

The construction industry is critical to economic growth and environmental sustainability. However, its substantial resource consumption and waste generation highlight the urgent need for a transition toward circular construction (CC) practices. This study uses scientometric and content analyses of 199 articles published between 2017 and 2024 to uncover the barriers to adopting CC principles. This study aims to identify these barriers, map key research trends, and propose future directions for addressing obstacles to CC adoption. This research focuses on global contributions to CC, highlighting influential nations, journals, and scholars and analyzing keyword trends over time. Additionally, it examines the recurring themes and patterns to provide a holistic understanding of the systemic challenges faced by the construction industry in embracing CC principles. By presenting the first comprehensive overview of barriers to CC, this study fills a critical research gap and offers insights for researchers and policymakers. The findings reveal that 12% of the total publications in the field originate from Australia and China, leading in contributions, while journals such as Sustainability and the Journal of Cleaner Production account for 31.5% of the articles. Keyword co-occurrence analysis identifies “management”, “barriers”, and “waste management” as prevailing themes. The annual growth rate of CC-related publications is 44.78%, underscoring its rising importance. Furthermore, 41 barriers to CC were revealed with content analysis. These insights offer a foundational understanding for policymakers and researchers, emphasizing collaboration, government intervention, and innovation in materials and technology to overcome barriers and transition to a circular, resource-efficient construction model. Full article

This comprehensive review examines the role of sustainable aviation fuels (SAFs) in promoting a more environmentally responsible aviation industry. This study explores various types of biofuels, including hydroprocessed esters and fatty acids (HEFAs), Fischer–Tropsch (FT) fuels, alcohol-to-jet (ATJ) fuels, and oil derived from algae. Technological advancements in production and processing have enabled SAF to offer significant reductions in greenhouse gas emissions and other pollutants, contributing to a cleaner environment and better air quality. The review addresses the environmental, economic, and technical benefits of SAF, as well as the challenges associated with their adoption. Lifecycle analyses are used to assess the net environmental benefits of SAF, with a focus on feedstock sustainability, energy efficiency, and potential impacts on biodiversity and land use. Challenges such as economic viability, scalability, and regulatory compliance are discussed, with emphasis on the need for supportive policies and international collaboration to ensure the long-term sustainability of SAF. This study also explores current applications of SAF in commercial airlines and military settings, highlighting successful case studies and regional differences driven by policy frameworks and government incentives. By promoting technological innovation and addressing regulatory and economic barriers, SAF has the potential to play a crucial role in the aviation industry’s transition toward sustainability. Full article

The hydrogenation of carbon monoxide (CO) offers a promising avenue for reducing air pollution and promoting a cleaner environment. Moreover, by using suitable catalysts, CO can be transformed into valuable hydrocarbons. In this study, we elucidate the mechanistic aspects of the catalytic conversion of CO to hydrocarbons on the surface of manganese-doped graphene oxide (Mn-doped GO), where the GO surface includes one OH group next to one Mn adatom. To gain insight into this process, we have employed calculations based on the density functional theory (DFT) to explore both the thermodynamic properties and reaction energy barriers. The Mn adatoms were found to significantly activate the catalyst surface by providing stronger adsorption geometries. Our study concentrated on two mechanisms for CO hydrogenation, resulting in either CH₄ production via the reaction sequence CO → HCO → CH₂O → CH₂OH → CH₂ → CH₃ → CH₄ or CH₃OH formation through the CO → HCO → CH₂O → CH₂OH → CH₃OH pathway. The results reveal that both products are likely to be formed on the Mn-doped GO surface on both thermodynamic grounds and considering the reaction energy barriers. Furthermore, the activation energies associated with each stage of the synthesis show that the conversion reactions of CH₂ + OH → CH₃ + O and CH₂O + OH → CH₂OH + O with energy barriers of 0.36 and 3.86 eV are the fastest and slowest reactions, respectively. The results also indicate that the reactions: CH₂OH + OH → CH₂ + O + H₂O and CH₂OH + OH → CH₃OH + O are the most exothermic and endothermic reactions with reaction energies of −0.18 and 1.21 eV, respectively, in the catalytic pathways. Full article

The pursuit for better skin health, driven by collective and individual perceptions, has led to the demand for sustainable skincare products. Environmental factors and lifestyle choices can accelerate skin aging, causing issues like inflammation, wrinkles, elasticity loss, hyperpigmentation, and dryness. The skincare industry is innovating to meet consumers’ requests for cleaner and natural options. Simultaneously, environmental issues concerning waste generation have been leading to sustainable strategies based on the circular economy. A noteworthy solution consists of citrus by-product valorization, as such by-products can be used as a source of bioactive molecules. Citrus processing, particularly, generates substantial waste amounts (around 50% of the whole fruit), causing unprecedented environmental burdens. Hesperidin, a flavonoid abundant in orange peels, is considered to hold immense potential for clean skin health product applications due to its antioxidant, anti-inflammatory, and anticarcinogenic properties. This review explores hesperidin extraction and purification methodologies as well as key skincare application areas: (i) antiaging and skin barrier enhancement, (ii) UV radiation-induced damage, (iii) hyperpigmentation and depigmentation conditions, (iv) wound healing, and (v) skin cancer and other cutaneous diseases. This work’s novelty lies in the comprehensive coverage of hesperidin’s promising skincare applications while also demonstrating its potential as a sustainable ingredient from a circular economy approach. Full article

Production planning and control (PPC), responsible for all the activities that keep production running regularly, plays an essential role in the transition to more sustainable manufacturing systems. PPC decision-making processes need to be driven by sustainable principles even if this makes them more effortful and complex from the strategic to operative level. This study aims to review the scientific literature relating to sustainable PPC. A bibliometric analysis of 437 papers published on the Scopus database was performed to identify the most relevant articles, authors, and journals and to provide the current topic trends and future research themes and gaps. The findings revealed the increasing interest in this topic mainly since 2018. China and the USA are the most productive countries, whereas the Journal of Cleaner Production and Sustainability are the most productive journals. The analysis has also highlighted the ways to address sustainability issues in PPC, e.g., by integrating in scheduling models objectives related to sustainability or by removing barriers to reverse logistics and circular economy at the PPC level. The following topics, instead, deserve further research: attention to the social issues in PPC and the development of decision support systems that will improve companies’ PPC decision-making capabilities in sustainable optics. Full article

Organizations moving towards adopting sustainable business development has become a necessity. As more and more stakeholders increasingly show interest in pollution and environmental degradation and the major impacts on the economic activities of organizations, it has become a necessity for organizations to move towards adopting sustainable business development. To achieve this goal, organizations need to invest in green innovations (GIs). Therefore, this paper examines the important influence of internal and external stakeholders on organizations that choose to pursue sustainable development with the help of implementing green innovations. It has certain theoretical and practical implications, but the following problems exist: (a) the usage of energy has increased in recent years and further creates a warning sign that precautionary measures need to be taken soon, and if not, the situation will impact the environment and organizations’ sustainable performance; (b) stakeholders’ raise concerns about pollution and environmental deterioration and urge industrialists to incorporate green innovation into all aspects of production and processes. A positivist research paradigm is applied, and the hypotheses will be tested using Structural Equation Modelling (SEM). This study analyzes how green innovation interacts with the linkage between stakeholders and organizational sustainable performance. The contribution hopes to benefit the growth of the economy, promote a cleaner environment, and enhance the wellbeing of the country. This study will further help to enlighten the importance of embracing green innovation in industries to policy makers and manufacturers, which is currently lacking. This initiative is in line with Malaysia’s 12th plan, which aims to promote green innovation to boost the Gross Domestic Product (GDP) and push the country above the high-income barrier. Full article

The purpose of this study is to evaluate the economic and environmental gains that result from the implementation of cleaner production in a small enterprise (SE) from the metal and mechanics industry, allowing for overcoming barriers and contributing to sustainable development goals. The research work builds on a case study that involved several data sources, including semi structured interviewing and non-participant observation. Data analysis involved the calculation of mass balance, building solid and liquid waste that were minimized in the process. The results suggest that cleaner production led to economic gains, by allowing for reduction in losses and promoting a better use of raw materials. It also led to environmental improvements by means of the implementation of a wastewater treatment station that allowed for the reuse of water in the manufacturing process. It was concluded that the economic gain in the project played a determinant role for the SE to overcome the barriers for the implementation of CP and leading to the reduction of the environmental impact in the abiotic, biotic, water and air compartments, as estimated with the Mass Intensity Factor. The study offers a timely and relevant contribution for the literature in the field, while offering insights for o managerial practice, and the attainment of the Sustainable Development Goals defined by the United Nations Development Program. Full article

The generation of hydrogen from water using light is currently one of the most promising alternative energy sources for humankind but faces significant barriers for large-scale applications due to the low efficiency of existing photo-catalysts. In this work we propose a new route to fabricate nano-hybrid materials able to deliver enhanced photo-catalytic hydrogen evolution, combining within the same nanostructure, a plasmonic antenna nanoparticle and semiconductor quantum dots (QDs). For each stage of our fabrication process we probed the chemical composition of the materials with nanometric spatial resolution, allowing us to demonstrate that the final product is composed of a silver nanoparticle (AgNP) plasmonic core, surrounded by satellite Pt decorated CdS QDs (CdS@Pt), separated by a spacer layer of SiO₂ with well-controlled thickness. This new type of photoactive nanomaterial is capable of generating hydrogen when irradiated with visible light, displaying efficiencies 300% higher than the constituting photo-active components. This work may open new avenues for the development of cleaner and more efficient energy sources based on photo-activated hydrogen generation. Full article

Pressure-driven processes have come a long way since they were introduced. These processes, namely Ultra-Filtration (UF), Nano-Filtration (NF), and Reverse-Osmosis (RO), aim to enhance the efficiency of wastewater treatment, thereby aiming at a cleaner production. Membranes may be polymeric, ceramic, metallic, or organo-mineral, and the filtration techniques differ in pore size from dense to porous membrane. The applied pressure varies according to the method used. These are being utilized in many exciting applications in, for example, the food industry, the pharmaceutical industry, and wastewater treatment. This paper attempts to comprehensively review the principle behind the different pressure-driven membrane technologies and their use in the removal of heavy metals from wastewater. The transport mechanism has been elaborated, which helps in the predictive modeling of the membrane system. Fouling of the membrane is perhaps the only barrier to the emergence of membrane technology and its full acceptance. However, with the use of innovative techniques of fabrication, this can be overcome. This review is concluded with perspective recommendations that can be incorporated by researchers worldwide as a new problem statement for their work. Full article

Small enterprises negatively affect the environment due to the inadequate disposal of manufacturing and raw material wastes generated in production processes; in addition, small enterprises do not often adopt adequate environmental practices due to barriers that include the lack of investment capacity. However, the adoption of cleaner production results in economic and environmental gains. The purpose of this study is to demonstrate how Brazilian small metal mechanical enterprises can identify and overcome barriers with the aim of implementing cleaner production. The research method used multiple cases with data collected by means of interviews and observations. The results allowed us to conclude that cultural and technical barriers negatively affect the adoption of cleaner production in the small enterprises studied. However, cultural and technical barriers can be overcome by means of economic and environmental gains as well as through investment in employee training and in the acquisition of more efficient machines and equipment. Full article

Microbial pigments, regarded as the most potential biomass pigments, have lately attracted increasing attention in textile dyeing due to their sustainability and cleaner production. The pyrrole structure microbial pigment, called prodigiosin, recently have become a research hotspot for its bright colors and antibacterial function. However, in most case the extraction and preparation are time-consuming and expensive processes since these kinds of microbial pigments are intracellular metabolites. In order to promote the application of microbial pigments in textile dyeing, a novel idea of preparing dye liquid of pyrrole structure pigments based on fermentation broth was put forward via increasing the proportion of extracellular pigments. A model membrane platform was established with a planar lipid bilayer to investigate transmembrane transport of microbial pigments and permeability barrier of cell membrane. The nano-dispersion of pigments was produced as the dye liquor owing to high-throughput transmembrane transfer of intracellular pigments and the increase of extracellular pigments proportion. The results indicated that the size and surface electrical properties of the pigments had contributed much to the mass transfer. It is also showed that transmembrane transmission of the intracellular pigments could be regulated by physical and chemical methods. With the improvement of transmembrane transfer efficiency of microbial pigments and the proportion of extracellular pigments, the complicated biological separation process could be avoided and the application of microbial pigments in textile dyeing can be promoted. Full article