Search Results (103)

Cellulosic raw materials are the most common source of carbon on Earth and are in great demand for the production of high-value-added products. Cellulosic feedstocks represent a strong matrix consisting of cellulose, lignin, and hemicelluloses. The efficient transformation of cellulosic raw materials into fermentable sugars requires the use of effective pretreatment strategies. The methods employed for pretreatment should be efficient, have low operating costs, and exhibit lower environmental impact. The present review describes pretreatment methods like liquid hot water (LHW) and steam explosion (SE) and highlights peculiar features, benefits and disadvantages of these processes. The effectiveness of these pretreatment methods and their effect on cellulosic raw materials strongly depends on the type of feedstock (component composition), pretreatment method, and pretreatment conditions (pressure, temperature, time, etc.). The LHW pretreatment requires neither addition of chemicals and catalysts nor grinding stage, but requires high energy inputs. The SE pretreatment is regarded as environmentally friendly and requires lower energy inputs, but contributes to the formation of toxic compounds. The life cycle assessment approach demonstrated that the SE pretreatment outperforms dilute acid pretreatment methods and allows the reduction of energy inputs, thereby improving the environmental performance of the process, while the LHW method improves long-term energy security and creates a greener future. Full article

Current biodiesel production is costly, in part due to the catalysts added during transesterification and later washed out. We have previously shown that intact rapeseed shells can be ball-milled with an alcohol to produce biodiesel without an added catalyst. Here, we report on the activation and identity of the complexing agent within the shells of rapeseeds and sunflower seeds. Lignin, present in the cell walls of plant matter, complexes with iron and manganese within metallic media, such as in a ball mill, and acts as a catalyst support in a transesterification reaction with oil and methanol. When ball-milled with methanol, rapeseed and sunflower seeds produce up to 90% biodiesel, similar to yields produced by industrial methods. However, this new method for producing biodiesel is a greener alternative, as it requires fewer organic solvents, may reduce the time and energy required for synthesis, and may reduce the effort required for product purification. Full article

The pharmaceutical industry faces mounting pressure to reduce its environmental impact while maintaining innovation in drug development. Artificial intelligence (AI) has emerged as a transformative tool across healthcare and drug discovery, yet its potential to drive sustainability by improving molecular design remains underexplored. This review critically examines the applications of AI in molecular design that can support in advancing greener pharmaceutical practices across the entire drug life cycle—from design and synthesis to waste management and solvent optimisation. We explore how AI-driven models are being used to personalise dosing, reduce pharmaceutical waste, and design biodegradable drugs with enhanced environmental compatibility. Significant advances have also been made in the predictive modelling of pharmacokinetics, drug–polymer interactions, and polymer biodegradability. AI’s role in the synthesis of active pharmaceutical compounds, including catalysts, enzymes, solvents, and synthesis pathways, is also examined. We highlight recent breakthroughs in protein engineering, biocatalyst stability, and heterogeneous catalyst screening using generative and language models. This review also explores opportunities and limitations in the field. Despite progress, several limitations constrain impact. Many AI models are trained on small or inconsistent datasets or rely on computationally intensive inputs that limit scalability. Moreover, a lack of standardised performance metrics and life cycle assessments prevents the robust evaluation of AI’s true environmental benefits. In particular, the environmental impact of AI-driven molecules and synthesis pathways remains poorly quantified due to limited data on emissions, waste, and energy usage at the compound level. Finally, a summary of challenges and future directions in the field is provided. Full article

In this work, a sustainable approach to reclaiming high-value anatase/rutile TiO₂ nanoparticles from deactivated or used selective catalytic reduction (SCR) catalysts is demonstrated using a composite flux (NaOH/Na₂CO₃) through an efficient sintering and subsequent leaching methodology. This method directly addresses the urgent need for circular economy strategies in industrial waste management. Sintering experiments revealed that while NaOH enhanced the separation efficiency of V₂O₅ and SiO₂, it led to agglomerated products, hindering TiO₂ recovery. In contrast, Na₂CO₃ enabled the production of powdery sintered residues, facilitating the complete separation of anatase/rutile TiO₂ nanoparticles, as confirmed by XRD. By optimizing the sintering-leaching conditions, this method achieves near-total recovery of TiO₂ with retained photocatalytic performance, ensuring its suitability for reuse in applications such as air/water purification or renewable energy systems. This study advances sustainability by repurposing industrial waste into high-performance materials, reducing the energy and resource demands associated with conventional TiO₂ synthesis, and preventing hazardous material leakage into ecosystems. The scalable, low-complexity process aligns with global sustainability goals, including responsible consumption (SDG 12), climate action (SDG 13), and industrial innovation (SDG 9), offering a blueprint for transforming waste streams into valuable resources for a greener economy. Full article

A heterogeneous polybenzimidazole-supported Mo(VI) catalyst and tert-butyl hydroperoxide (TBHP) as an oxidising reagent have been utilised to establish a more environmentally friendly and greener alkene epoxidation process. A polybenzimidazole-supported Mo(VI) complex (PBI.Mo) has been prepared, characterised and evaluated successfully. The stability and catalytic activity of the produced catalyst have been evaluated for the epoxidation of 1,7-octadiene and 1,5-hexadiene in a jacketed stirred batch reactor to assess its performance towards these alkenes. The suitability and efficiency of the catalyst have been compared by studying the effect of reaction temperature, feed mole ratio of alkene to TBHP, catalyst loading, and reaction time on the yield of 1,2-epoxy-5-hexene and 1,2-epoxy-7-octene. Response surface methodology (RSM) using Box–Behnken Design (BBD) has been employed to design experimental runs and study the catalytic performance of the PBI.Mo catalyst for all batch experimental results. A quadratic regression model has been developed representing an empirical relationship between reaction variables and response, which is the yield of epoxides. The numerical optimisation technique concluded that the maximum yield that can be reached is 66.22% for 1,7-octadiene and 64.2% for 1,5-hexadiene. The reactivity of alkenes was observed to follow the sequence 1,5-hexadiene > 1,7-octadiene. The findings of this study confirm that the optimal reaction conditions vary between the two reactions, indicating differences in catalytic performance for each alkene. Full article

The so far unattended version of the Hirao reaction involving the coupling of the less reactive chloroarenes with >P(O)H reagents, such as diarylphosphine oxides, diethyl phosphite, and ethyl phenyl-H-phosphinate, was investigated in detail using Pd(OAc)₂ as the catalyst precursor, and applying some excess of the P-reagent to provide the ligand via its trivalent tautomeric (>P-OH) form. In the presence of triethylamine, no P–C coupling took place, meaning that there was a need for a stronger base, an alkali carbonate. The solvent had a significant effect on the efficiency of the Hirao reaction. The optimum conditions (10% of the Pd(OAc)₂, 1.3 equiv. of the P-reagent, 1.1 equiv. of the alkali carbonate, 135–150 °C) explored herein were applied in the synthesis of diaryl-phenylphosphine oxides, aryl-diphenylphosphine oxides, diethyl arylphosphonates, and ethyl diphenylphosphinate. Theoretical calculations performed at the M06-2X/6-31G(d,p)[PCM(MeCN)] level also justified coupling with the chloroarenes under appropriate conditions, and were in accord with the experimental results revealing the unsuitability of triethylamine as a base and the need for an alkali carbonate. The new protocol elaborated herein is more practical and “greener” than the version with bromoarenes, and embraces a wide substrate scope. Full article

Palladium nanoparticles (PdNPs) are transforming the landscape of modern catalysis and offer sustainable and efficient alternatives to traditional catalysts for cross-coupling reactions. Owing to their exceptional surface area-to-volume ratio, PdNPs exhibit superior catalytic activity, selectivity, and recyclability, making them ideal for greener chemical processes. Recent innovations have focused on improving the stability and reusability of PdNPs through environmentally benign approaches, such as water-based reactions, renewable stabilizers, and magnetic nanoparticle supports. Advances in catalyst design, including PdNP immobilization on magnetic nanosilica for enhanced recyclability in Suzuki–Miyaura reactions, nitrogen-doped carbon nanosheets achieving up to ninefold improvements in turnover frequencies, and biodegradable biopolymer matrices that reduce environmental impact, have effectively addressed key challenges such as catalyst leaching, support degradation, and agglomeration. The shift from conventional catalysis to these cutting-edge nanocatalytic techniques signifies a critical movement toward sustainable chemistry, positioning PdNPs at the forefront of industrial applications and the future of eco-friendly chemical synthesis. Full article

The single-atom catalysts (SACs) for the electrocatalytic nitrogen reduction reaction (NRR) have garnered significant attention in recent years. The NRR is regarded as a milder and greener approach to ammonia synthesis. The pursuit of highly efficient and selective electrocatalysts for the NRR continues to garner substantial interest, yet it poses a significant challenge. In this study, we employed density functional theory calculations to investigate the stability and catalytic activity of 29 transition metal atoms loaded on the two-dimensional (2D) AlN monolayer with Al monovacancy (TM@AlN) for the conversion of N₂ to NH₃. After screening the activity and selectivity of NRR, it was found that Os@AlN exhibited the highest activity for NRR with a very low limiting potential of −0.46 V along the distal pathway. The analysis of the related electronic structure, Bader charge, electron localization function, and PDOS revealed the origin of NRR activity from the perspective of energy and electronic properties. The high activity and selectivity towards the NRR of SACs are closely associated with the Os-3N coordination. Our findings have expanded the scope of designing innovative high-efficiency SACs for NRR. Full article

The metabolic activities of microorganisms to modify the chemical structures of organic compounds are an effective tool for the production of high-value steroidal drugs or active pharmaceutical ingredients (APIs). The integration of biotransformation into the synthesis of APIs can greatly reduce the number of reaction steps and achieve higher process efficiency, thus enabling their greener production. The current research efforts are focused on either the optimization of existing processes or identification of new potentially useful bioconversions. This study aimed to assess the catalytic abilities of the filamentous fungus Fusarium culmorum AM 282 to transform B-nor analogues (5(6→7)abeo compounds) of steroid hormones: androstenedione (AD), dehydroepiandrosterone (DHEA) and its acetate. Our previous studies have demonstrated that this strain is an active hydroxylating catalyst for many steroidal compounds with diverse structures. The results presented in this work showed that the hydroxylation of B-nor steroids occurred with the regio- and stereoselectivity typical of this strain in relation to the corresponding natural hormones of the standard 6:6 A/B series. After the transformations of B-nor-DHEA and its acetate, 15α-hydroxy-B-nor-DHEA was obtained as the sole product of the reaction, while the transformation of the AD analogue resulted in a mixture of its 15α- and 6α-hydroxy derivatives. A detailed analysis of the transformation course indicated that all the obtained hydroxy derivatives could be the result of the activity of the same enzyme. The presented results may provide a basis for research aimed at understanding the molecular nature of cytochrome P-450 monooxygenase from F. culmorum AM 282 with its ability for 15α-hydroxylation of steroidal compounds. An analysis of the pharmacokinetic and pharmacodynamic properties of the obtained metabolites with cheminformatics tools suggests their potential biological activity. Full article

The growth of the environment depends upon developing greener and ecological methods for managing pollutants and contamination from industrial wastewater, which causes significant effects on human health. The removal of these pollutants from wastewater using nanomaterials covers an ecological method that is free from expensive and secondary pollution. In this report, we developed magnetic iron nanoparticles from Chenopodium glaucum (CG), which showed excellent adsorption capacity at pH 5 for selective Hg²⁺ and Pb²⁺ metal ions among various heavy metal ions, with maximum adsorption capacities of 96.9 and 94.1%, respectively. These metals’ adsorption process conforms to the Langmuir model, which suggests that monolayer adsorption transpires on CG–Fe₂O₃ nanoparticles. CG–Fe₂O₃ nanoparticles also act as an efficient and recyclable heterogeneous catalyst for one-pot synthesis of xanthene derivatives, yielding products with high yields (up to 97%) and excellent purity (crystalline form) within a short timeframe (6 min) using microwave irradiations (at 120 W). Full article

Fiber-reinforced composites (FRCs) represent a promising class of engineering materials due to their mechanical performance. However, the vast majority of FRCs are currently manufactured using carbon and glass fibers, which raises concerns because of the difficulties in recycling and the reliance on finite fossil resources. On the other hand, the use of natural fibers is still hampered due to the problems such as, e.g., differences in polarity between the reinforcement and the polymer matrix components, leading to a significant decrease in composite durability. In this work, we present a natural fiber-reinforced composite (NFRC), incorporating plasma pre-treated flax fibers as the reinforcing element, thermoplastic polylactic acid (PLA) as a matrix, and a key point of the current study—a thermoset coating based on epoxidized linseed oil for adhesion improvement. Using atmospheric plasma-jet treatment allows for increasing the fiber’s surface energy from 20 to 40 mN/m. Furthermore, a thermoset coating layer based on epoxidized linseed oil, in conjunction with dodecyl succinic anhydride (DDSA) as a curing agent and 2,4,6-tris(dimethyl amino methyl) phenol (DMP-30) as a catalyst, has been developed. This coated layer exhibits a decomposition temperature of 350 °C, and there is a substantial increase in the dispersive surface-energy part of the coated flax fibers from 8 to 30 mN/m. The obtained natural fiber-reinforced composite (NFRC) was prepared by belt-pressing with a PLA film, and its mechanical properties were evaluated by tensile testing. The results showed an elastic modulus up to 18.3 GPa, which is relevant in terms of mechanical properties and opens up a new pathway to use natural-based fiber-reinforced bio-based materials as a convenient approach to greener FRCs. Full article

The electrochemical reduction of carbon dioxide (CO₂) to methane (CH₄) holds tremendous potential in mitigating greenhouse gas emissions and producing renewable fuels. Thus, this review provides a comprehensive overview of the utilization of copper-based metal–organic frameworks (Cu-MOFs) as catalysts for this transformative process. Diverse key aspects of Cu-MOFs that make them ideal candidates for CO₂ reduction are discussed, including their high surface areas, tunable pore sizes, and customizable active sites. Furthermore, recent advances in the design and synthesis of Cu-MOFs tailored specifically for enhanced catalytic activity and selectivity towards CH₄ production are highlighted. Additionally, mechanistic insights into the CO₂ reduction process on Cu-MOF catalysts are examined. Moreover, the recent application of diverse Cu-MOFs and derived materials in electrochemical reduction systems is discussed, and future research directions and potential applications of Cu-MOFs in sustainable energy conversion technologies are outlined. Thus, this review provides valuable insights into the current state of the art and the prospects for utilizing Cu-MOFs as efficient catalysts for the electrochemical conversion of CO₂ to CH₄, offering a pathway towards a greener and more sustainable energy future. Full article

We report the reticular synthesis and structural investigations through the spectroscopic analysis of a novel polyhedral oligomeric silsesquioxane (POSS)-modified framework, hereby ascribed as a catalyst for the selective reduction of aryl nitriles to amines. The integration of the unique features of the polyhedral oligomeric silsesquioxane with 2,2′-Bipyridine-4,4′-dicarboxaldehyde and subsequently coordination to cobalt acetate manifests a distinctive feature, which is a stable covalent bond between Co and the functionalized POSS, effectively preventing catalyst leaching. The cobalt acetate-modified POSS–COF, synthesized with this approach, underwent a comprehensive characterization employing various analytical techniques including FTIR, XRD, SEM, XPS, TGA, and ²⁹Si NMR. This thorough characterization provides a detailed insight into the structural and chemical attributes of the catalyst. Our catalyst, with its exceptional catalytic efficiency in catalyzing reduction reactions compared to its homogeneous counterparts, and its distinctive three-dimensional metalated POSS system, shows outstanding catalytic performance attributed to its diverse coordination interactions with ligands. Moreover, this catalyst presents additional merits, such as facile recovery and recyclability, making it a promising candidate for sustainable and efficient catalytic processes and thus instilling hope for a greener future. Full article

The amalgamation of sustainable practises throughout the fabrication process with advanced material engineering holds promise not only for eco-conscious manufacturing but also for promoting technological advancements in versatile material design and application. Moreover, technological innovation serves as a catalyst for sustainability initiatives, driving innovation and enabling the adoption of greener practises across industries. This study investigates redefining the production protocol of pressure spinning to produce core–sheath polymer fibres, deepening sustainable practises. It aims to explore innovative approaches such as modifying spinning parameters, optimising polymer solvent configurations and understanding fluid behaviour to curtail material wastage and maintain minimal energy consumption without compromising production efficiency. Utilising Polyvinylpyrrolidone (PVP) for the core and Polyethylene oxide (PEO) for the sheath, production rates of up to 64 g/h were achieved with a fibre diameter range of 3.2 ± 1.7 µm to 4.6 ± 2.0 µm. Energy consumption per mass of fibres produced showed a decreasing trend overall with increasing applied gas pressure. These findings highlight the potential for the efficient and scalable production of core–sheath fibres with applications in various advanced materials fields. Full article

γ-valerolactone (GVL), derived from biomass, is a crucial platform compound for biofuel synthesis and various industrial applications. Current methods for synthesizing GVL involve expensive catalysts and high-pressure hydrogen, prompting the search for greener alternatives. This study focuses on a novel zirconium phosphate (ZrP)-pillared zeolite MCM-36 derivative catalyst for converting levulinic acid (LA) to GVL using alcohol as a hydrogen source. The incorporation of ZrP significantly contributes to mesoporosity and greatly enhances the acidity of the catalysts. Additionally, we employed ³¹P MAS NMR to comprehensively investigate the influence of phosphorus species on both the acidity and the catalytic conversion of LA to GVL. By adjusting the Zr-to-P ratios, we synthesized catalysts with enhanced acidity, achieving high conversion of LA and selectivity for GVL. The catalyst exhibited high recyclability, showing only minor deactivation over the course of five cycles. Furthermore, the catalyst was successfully applied to the one-pot conversion of furfural to GVL, showcasing its versatility in biomass conversion. This study highlights the potential of the MCM-ZrP1 catalyst for sustainable biomass conversion and offers insights for future research in renewable energy technologies. Full article