Current Opinion in Green and Sustainable Chemistry最新文献

A challenge for the future is the valorization of food waste to obtain a plethora of food additives, chemicals, biodegradable polymers, materials, and energy, with the overarching goal of mitigating the environmental impact of these residues. Many of these wastes are an important source of natural pigments with biofunctional properties. Furthermore, the growing awareness of the potential side effects of synthetic colorants and the demand for healthier foods featuring clean labels have driven to new techniques for extracting these coloring compounds from natural sources. Non-conventional green extraction techniques are gaining momentum due to their higher extraction yields, low environmental impact, and better protection of pigments against degradation compared to conventional extraction methods. On the other hand, encapsulation of biocompounds is presented as the alternative to improve pigment stability. In this concise review, cutting-edge methodologies and innovations used in the extraction and stabilization of natural pigments by encapsulation will be discussed.

The scientific and industrial communities worldwide have recently achieved impressive technical advances in developing innovative electrocatalysts and electrolysers for water and seawater splitting. The viability of water electrolysis for commercial applications, however, remains elusive, and the key barriers are durability, cost, performance, materials, manufacturing, and system simplicity, especially with regard to running on practical water sources like seawater. This article, therefore, primarily aims to provide a concise overview of the most recent disruptive water-splitting technologies and materials that could reshape the future of green hydrogen production. Starting from water electrolysis fundamentals, the recent advances in developing durable and efficient electrocatalysts for modern types of electrolysers, such as decoupled electrolysers, seawater electrolysers, and unconventional hybrid electrolysers, have been represented and precisely annotated in this report. Outlining the most recent advances in water and seawater splitting, the article can help as a quick guide in identifying the gap in knowledge for modern water electrolysers while pointing out recent solutions for cost-effective and efficient hydrogen production to meet zero-carbon targets in the short to near term.

Benzene, toluene, and xylenes (BTX), as well as their downstream products, are a fundamental part of numerous processes in the chemical industry. However, by now, aromatics are still yielded from fossil resources like naphtha, coal, and natural gas. Thus, to push the chemical industry further toward renewability, the production of bio-based aromatics is an essential step to take. The implementation of bio-based aromatics to replace petrochemical aromatics can proceed in two main ways: as direct replacement via renewable drop-in or as replacement by renewable functional alternatives. However, the implementation of both pathways still requires significant process optimization toward large-scale application in industrial processes. In this work, renewable drop-in is mainly discussed in the context of pyrolysis and Diels–Alder reactions. Furthermore, renewable functional alternatives discussed here focus on furan derivatives and lignin-based building blocks.

The discarded electrical equipment has become the leading waste problem worldwide. The safe and sustainable disposal of electronic waste (e-waste) is challenging because it is composed of both hazardous and non-hazardous substances. Concurrently, geopolymers offer multifaceted benefits and have potential applications, particularly in the realm of building materials. Drawing inspiration from these circumstances, this article delves into the possibility of using non-metallic fractions of e-waste—such as plastic (e-plastic) and glass (e-glass)—as aggregates or/and precursors in geopolymer production. The characteristics of these e-waste components, their suitability for incorporation, and the rationale behind their selection form a focal point of this article. The literature suggests that incorporating less than 50% of e-waste fractions to produce geopolymers exhibits adequate compressive strength to fabricate at least medium-grade construction materials. However, more experimental investigations are required in this domain to explore and optimize the utilization of such composites in various applications in the construction industry.

Artificial intelligence (AI) including machine learning (ML) has played a leading role in advancing biofuel technology with applications ranging from product yield prediction, optimization of process conditions, and preliminary evaluation of economic and environmental impacts of biomass to biofuel technologies. This review presents an overview of recent study within the past two years that evaluates the applications of ML in advancing biofuels technology. These studies are grouped into three distinct categories: Screening and discovery of new materials; optimization of process; decision-making. Furthermore, the applications of ML/AI in preliminary economic and environmental assessment of biomass to biofuel technologies are discussed.

The utilization of nanomaterials in biofuel production has garnered considerable attention owing to their distinctive characteristics, including a high surface-area-to-volume ratio, strong dispersibility, and enhanced reactivity. This review delves into the transformative role played by nanomaterials, specifically graphene-based catalysts, metal–organic frameworks, biomass waste materials, and carbon nanotubes, in augmenting various facets of biofuel production. Noteworthy examples include the application of metal-modified graphene oxide composite catalysts, incorporating aluminium and ferric, revealing a significant 25% reduction in free fatty acid content and a remarkable 15% increase in methyl hexadecanoic yield. Furthermore, the eco-friendly synthesis of TiO₂ nanoparticles showcased consistently high biodiesel yields, reaching 95% over 10 cycles, underscoring its economic advantages and stability. However, it is essential to acknowledge the potential drawbacks associated with nanomaterial utilization in biofuel production. Environmental concerns, such as nanoparticle release during production processes and their impact on ecosystems as well as safety issues related to exposure to nanoparticles, require careful consideration. This comprehensive overview encompasses recent studies on green synthesis, hydrothermal-assisted carbonization, gold nanoparticles in biomass hydrolysis, and the impact of nano-fuel technology on engine characteristics. Innovations in catalysts and processes, such as sulfonic acid functionalized metal–organic frameworks and magnetic MOF-derived materials, are scrutinized for their sustainability. The review culminates with a thorough analysis of the environmental and economic impacts, accentuating both the potential benefits and challenges entailed in the seamless integration of nanotechnology into biofuel production.

Recent years have seen a growing convergence between digital, physical, and biological disciplines, heralding a major shift in agriculture and the food industry, led by advanced technologies, such as artificial intelligence, big data, smart sensors, robotics, three-dimensional printing, and blockchain, among others. These technological innovations constitute the core of the Fourth Industrial Revolution (called Industry 4.0) that is currently reshaping many agri-food sectors, including the dairy industry. Growing evidence shows that harnessing the power of Industry 4.0 technologies in the dairy sector could have several benefits, such as improved quality, traceability, and productivity, decreased production cost and time, and most importantly, from a sustainability point of view, reduced waste and by-products. This short review will focus on the potential of leveraging Industry 4.0 technologies in the reduction and valorization of waste and by-products in the dairy sector.

Synthesizing defined facets/morphologies with atomic precise arrangements and testing them to control catalytic activity and selectivity is gaining traction. Researchers from different backgrounds took serious initiatives to explore this young area of research. Since there are no clear guidelines in the literature demonstrating the ideal method (or a method that most approximates reality) in determining the facets of the materials, it can be seen that there are many recent studies which proposed methods that are highly prone to overinterpretation or even wrong, which leads to precarious conclusions in this field. Therefore, it is our aim here to demonstrate the main points of confusion between the definitions and practices. Our contribution concludes with recommendations and an outlook.

One of the most versatile platform chemicals that can be produced from lignocellulosic biomass with acid catalysis is 5-hydroxymethylfurfural (HMF). Deep eutectic solvents (DES), which are mixtures of hydrogen bond acceptor and hydrogen bond donor compounds that form low-melting point complexes are environmentally friendly and can be advantageously in HMF production as reaction phase, catalyst, co-catalyst, separation additive, or biphasic extractant. In this review, HMF production from biomass-derived carbohydrates along with the role of DES are highlighted with challenges being qualitatively assessed according to applicability, relative solvent cost, chemical safety, and R3 (reduce, reuse, recycle) indicators.

Continuous flow processes have distinct advantages over batch chemistry when it comes to long-term sustainability in the chemical industry, and they are widely acknowledged as being a greener approach to synthesis. However, despite this, the high costs and complexity of current commercial systems act as barriers to entry in this key technology for new entrants, stymieing chemists transition to continuous flow. In this overview, we discuss how 3D printing has emerged as a transformative force for chemists seeking to move into continuous flow. Alongside the physical equipment and microreactors, recent reports on incorporation of catalysts into 3D-printed reactors offers great promise for recyclability and environmental sustainability and the combined convergence of 3D printing and catalysis represents a transformative shift toward environmentally conscious, efficient, and standardized chemical processes in continuous flow.