Current Opinion in Green and Sustainable Chemistry最新文献

Researchers worldwide have significantly emphasized utilizing green adsorbents for environmental remediation to ensure a sustainable and secure environment. A promising avenue in this endeavor involves the production of biochar through the pyrolysis of sewage sludge. This review offers a contemporary exploration of sewage sludge pyrolysis, emphasizing the generation of a crucial solid fraction, namely biochar. This review delves into the physio-chemical attributes of biochar, encompassing elemental composition, specific surface area, pore size and volume, functional groups, surface morphology, and heavy metal content. Furthermore, the study discusses recent advancements in the adsorption capabilities of sewage sludge-derived biochar, specifically in removing metals, emerging pollutants, and dyes from wastewater, along with carbon capture. This biochar proves promising in both pollutant removal and the effective management of large sewage volumes. Despite these advancements, the research field warrants further attention, particularly in addressing technological features and sustainability considerations.

Pyrometallurgy is a well-known method for the efficient recovery of valuable metals from spent lithium-ion batteries (LIBs). This work provides an overview of the key aspects and recent advancements in pyrometallurgical processes for LIBs recycling. The newly developed pyrometallurgical processes have the potential to be energy-efficient, especially when utilizing microwave technologies. Despite encountering certain challenges and limitations, the prospects for recovering LIBs through pyrometallurgy appear promising, especially considering the anticipated rise in the number of spent LIBs for recycling.

The study explores the essential role of Life Cycle Assessment (LCA) in assessing the environmental sustainability impacts of biochar as a green sorbent in soil remediation. Recent studies from 2021 to 2023 underscore biochar's potential for global warming mitigation and carbon sequestration. The review discusses various concerns related to biochar-to-soil LCA, including its effects on heavy metals and pesticides in soils, the necessity for additional research on application frequency for pollutant sorption, impacts on real/different soil carbon stocks, variability in biochar properties, limited long-term studies, potential health implications, and incomplete assessment of pollutant dynamics, considering different biochar production methods and soil surface albedo. Advocating for LCAs for other green sorbents, such as low-cost clay, chitosan, and green nano-sorbents, is essential. Additionally, the integration of multiple green remediation techniques is proposed to enhance overall efficiency in soil and environmental remediation practices.

Biowastes are waste materials of organic/biological origin. The aim of this paper was to discuss the recent breakthroughs in the thermochemical conversion of biowastes to green adsorbents for pollutant uptake. The review also discussed how thermochemical conversion impacts adsorbent cost considerations after their use in water decontamination. The nature of the biowaste feedstock and process temperature are important in controlling the biochar properties, especially those relevant to pollutant removal. Considering that biowaste tends to have wide compositional variations with each batch (especially from home and municipal waste), it would be difficult to fully tune properties based on composition. Biochar can have good cost performance when applied for pollutant removal since its adsorptive capacity tends to be high for a wide range of pollutants. The simplicity and efficiency of thermochemical processes ensure they will continue to be a reliable choice for researchers in adsorbent synthesis.

Safe-and-sustainable-by-design (SSbD) is central in the European Chemicals Strategy for Sustainability, yet a common understanding of what SSbD is in concept and in practice is still needed. A comparison of current SSbD descriptions and approaches was made and lessons learned were derived from value chain discussions (packaging, textile, construction, automotive, energy materials, electronics, and fragrances value chains) to help provide input on how to implement SSbD in practice. Five important building blocks were identified: design, data, risk and sustainability governance, competencies, and social and corporate strategic needs. Other lessons learned include the identification of the biggest safety and sustainability challenges in a lifecycle-thinking approach towards the development of purpose-driven innovations, and connecting trans-disciplinary experts to the innovation process, already from the early phases. A clear understanding of what SSbD is and how to implement the SSbD framework is needed with clear procedures and incentives to support the industrial sector, especially SMEs.

Spatially confined photoexcitation of the photoresist is essential to achieve a high spatial resolution for stereolithography and related 3D printing; while for the photopolymerization initiated by conventional organic dyes based on one photon absorption, it is impossible to achieve localized excitation due to the linear correlation between excitation power and excited state concentration; usually, all the molecules in the whole beam path were excited. Photon upconversion technology provides the possibilities for spatially confined photoexcitation to achieve high spatial resolution due to the nonlinear optical characteristics. Three different upconversion technologies have been employed to assist the photopolymerization process. This review was organized according to the mechanisms of the upconversions and summarized the progress of stereolithographic 3D printing enabled by two-photon absorption, upconversion nanoparticles, and triplet-triplet annihilation, the research progresses in the last two years were specially emphasized.

The current scenario of human urine being directly discharged into the environment without recycling, despite being an economical source of fertilizer. Train coaches are the major source of large-scale urine waste generation. Adopting a circular economy creates significant synergies toward usages of water generated after nutrient recovery from urine. Some advanced decentralized treatment systems, such as electrochemical, bioelectrical, or reverse osmosis, would be useful to treat and recover nutrients from urine waste/wastewater. The laborious and costly affair of removing nutrients like N, P, and K from human urine needed a sustainable solution. These recovered nutrients can be reused as fertilizers in irrigation and, indirectly, in large-scale biodiesel production by being used in microalgae cultivation. However, the potential of reusing human urine waste is yet to be explored commercially. Additionally, artificial intelligence may be explored with sustainable approaches for urine separation and recycling soon.

Our polymer material and processing industry heavily relies on single- and twin-screw extrusion technology. To facilitate a circular economy technological upgrades, bridging experimental characterization techniques and the predictive power of modeling and software tools are although indispensable. The current work highlights engineering challenges and solution strategies to make (reactive) extrusion technology more sustainable and reliable. Molecular scale-driven case studies are included dealing with (i) energy and residence time optimization, (ii) the enlargement of the pool of polymers to be processed or synthesized (e.g. biopolymers and more well-defined compatibilizers), and (iii) polymer recycling applications, both chemical and mechanical. These case studies consider linear, branched, as well as cross-linked polymers.

In the last one hundred years, our comfort and life expectancy have increased exponentially compared to what humanity has experienced throughout its existence, primarily due to technological progress and much easier access for everyone to products and technologies that make our daily lives easier. But all this came with an equally significant increase in material consumption and the generation of huge amounts of residues. One of the resources that has been majorly affected in the last century is water. Although it is the most abundant substance on the planet, its quality has continuously decreased due to lifestyle. This short article deals with the possibility of filtering water in the near future using membranes based on natural polymers, assuring a more sustainable recirculation and reuse of water in the context of the circular economy. The challenges that this new paradigm raises, as well as the technological limitations, will also be discussed and presented.