Current Opinion in Green and Sustainable Chemistry最新文献

Vegetables and fruits are among the most widely consumed foods in the world. Because of consumption and industrial processing, huge amounts of by-products are generated, causing important environmental and economic problems. However, these wastes present a high content of bioactive compounds making its recovery an excellent opportunity to enhance sustainability and reduce food waste. This review highlights the main bioactive compounds and health benefits of vegetable and fruit by-products and their main applications, toward circular economy, making a critical review for their valorization.

At a time of rising raw material and energy prices, as well as growing awareness of the green transition approach, sustainability is becoming an increasingly important issue in the pharmaceutical industry. Research is actively addressing these issues, driven by changing market demands. In this brief review, we present 5 topics that we believe will play an important role in achieving sustainable continuous crystallization in present, and will continue to do so in the future. In particular, this review focuses on the developments made over the past three years towards continuous crystallization of biomolecules, enantioselective crystallization, new crystallizer designs, process integration of continuous crystallization as well as computer-aided process optimization in crystallization and their contribution to the principles of green chemistry and engineering.

The production of green diesel and jet bio–fuel takes place by hydrodeoxygenation (HDO) through hydrotreatment of natural triglycerides. This demands high pressurized external H₂ related to high cost as well as safety and environmental issues. The utilization of green H₂ released in situ from green solvents or side HDO products is essential for making the process safer, environmentally friendly and economically beneficial. Recent publications dealing with the utilization of this kind of hydrogen in the HDO of fatty biomass as well as the use of aqueous solutions in the HDO of waste cooking and algae oils containing appreciable amounts of water, are reviewed for the first time. Suggestions for future research in the field are formulated through critical comments at the end of the article.

Supramolecular chemistry exploits non-covalent intramolecular interactions to form structures such as host-guest complexes and crystalline porous materials. Supramolecular materials have potential for applications in a future sustainable society, such as energy-efficient separation, pollution remediation, or energy storage, but their production frequently relies on unsustainable methods. Flow chemistry is a technique that offers opportunities for ‘greener’ synthesis and that has recently found use in the supramolecular field. This review highlights recent examples to illustrate how flow chemistry can benefit the supramolecular chemist in terms of sustainability, process control, optimisation, and scale, ultimately providing viable routes to applications.

In recent years, the alarming surge in resource consumption has heightened global environmental awareness, prompting a critical examination of consumer behavior and production practices. The realization of the potentially catastrophic implications of these patterns on sustainability has led to a growing recognition of impending ecological challenges and the potential for social and economic collapse. Against this backdrop, the scientific community has witnessed significant advancements in the realms of circular economy and bioeconomy, emphasizing the need for holistic business models to underpin a circular bioeconomy. This short communication aims to emphasize the indispensable role of comprehensive business models within the circular (bio)economy, making a valuable contribution to existing literature. By focusing on the combination and profound impact of these models, the communication seeks to guide businesses towards success by aligning with the core principles of the circular economy. Delving into the essential components of a successful business model within the circular bioeconomy, this work offers insights crucial for policymakers, decision-makers, academia, industry professionals, engineers, and other key stakeholders. Through these insights, the communication strives to foster a deeper understanding and encourage the adoption of strategies that promote sustainability and resource efficiency in the dynamic landscape of the contemporary global economy while at the same time providing limitations and barriers to be expected for such implementations.

Renewable ammonia can be the path to decarbonization of food, chemicals, and the transport system. While lately, electrochemical hydrogen and air separation are gaining support, biomass-based ammonia can provide an alternative to contribute to green ammonia deployment with possible synergic with the current ammonia facilities. Different processing paths have been considered, depending on the wet content of the biomass. Wet biomass yield to ammonia is low, but it is more interesting as a waste management procedure. Biomass gasification has attracted most of the attention and results in promising ammonia production prices using technologies already in the toolbox of the process industry. The combination of ammonia and urea production solves one of the most significant challenges in biomass-based ammonia, the released CO₂. These integrated facilities allow for the full utilization of biomass in the green chemical industry.

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.