RSC sustainability最新文献

{"title":"Task-specific boronium ionic liquids as ashless lubricant additives†","authors":"Novina Malviya, Farah Fazlina M. Yasin, Maria Teresa Sateriale, Fergal Coleman, H. Q. Nimal Gunaratne, Andrea Dolfi, Geetha Srinivasan and Małgorzata Swadźba-Kwaśny","doi":"10.1039/D4SU00451E","DOIUrl":"10.1039/D4SU00451E","url":null,"abstract":"<p >Modern engines are designed for very close contact between shearing planes, which requires high-performance boundary lubrication, delivered by lubricant base oils formulated with an array of additives. Commercial additive packages typically contain metals, sulfur, and phosphorus, which act as poisons to catalytic converters (thereby increasing emissions), increase wear and contribute to corrosion (which lowers the lifespan of engines). Ionic liquids (ILs), which are low-melting organic salts, have been extensively studied as lubricant additives; although some commercially available ionic liquids perform well as friction modifiers, they suffer from low solubility in the oil matrix and may cause corrosion due to residual chloride content. Here, we report nine new, task-specific ionic liquids, designed to act as ashless lubricant additives, comprising boron-containing cations for enhanced wear reduction, carboxylic acid anions to reduce friction, and modified alkyl chains to enhance solubility in the base oil. All ILs were inherently free from metals, sulfur, and phosphorus, and synthesised through a halide-free route. Their speciation was studied through multinuclear NMR and Raman spectroscopies, followed by studies of solubility in Group III+ base oil. Their performance as lubricant additives was assessed in terms of friction reduction and wear scar reduction, benchmarked against glycerol mono-oleate (GMO), a commercially availabe lubricant additive.</p>","PeriodicalId":74745,"journal":{"name":"RSC sustainability","volume":" 10","pages":" 3100-3113"},"PeriodicalIF":0.0,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/su/d4su00451e?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142192800","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Molecular and material property variations during ideal PET degradation and mechanical recycling","authors":"Chiara Fiorillo, Lynn Trossaert, Erion Bezeraj, Simon Debrie, Hannelore Ohnmacht, Paul Van Steenberge, Dagmar R. D'hooge, Mariya Edeleva","doi":"10.1039/d4su00485j","DOIUrl":"https://doi.org/10.1039/d4su00485j","url":null,"abstract":"Poly(ethylene terephthalate) (PET) is an important polyester utilized for a wide variety of applications such as bottles, fibers and engineering compositions. Its chemical composition depends on the use of main monomers (e.g. terephthalic acid and ethylene glycol) as well as comonomers (e.g. diethylene glycol and isophthalic acid) in low amounts, defining several reaction pathways upon degradation or (mechanical) recycling. The present work gives a detailed overview of these molecular pathways, differentiating between thermal, thermo-mechanical, thermo-oxidative, photo-oxidative, hydrolytic and enzymatic degradation reactions. Considering at most low contaminant amounts, hence, under ideal (mechanical) recycling (lab) conditions, a wide range of functional group variations is already revealed, specifically during consecutive polyester processing cycles. Moreover, as a key novelty it is explained how the molecular variations influence the material behavior, considering both rheological, thermal and mechanical properties. Supported by basic life cycle analysis, it is highlighted that our future improved assessment of the mechanical recycling potential must better link the molecular and material scale. Only such linkage will open the door to a well-balanced polyester waste strategy, including (i) the evaluation of the most suited recycling technology at industrial scale, dealing with the mitigation of contaminants, and (ii) its further adoption and design in the context of the overall virgin and recycling market variation.","PeriodicalId":74745,"journal":{"name":"RSC sustainability","volume":"25 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142192805","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Volatile fatty acid extraction from fermentation broth using hydrophobic ionic liquid and in-situ enzymatic esterification","authors":"Ramkrishna Singh, Nikhil Kumar, Prathap Parameswaran, Blake A. Simmons, Kenneth L Sale, Ning Sun","doi":"10.1039/d4su00346b","DOIUrl":"https://doi.org/10.1039/d4su00346b","url":null,"abstract":"Efficient recovery of volatile fatty acids (VFAs) from fermentation broth is a challenge due to low VFA titers and thus limit the commercialization of VFA production using biological routes. Liquid-liquid extraction using hydrophobic ionic liquids (ILs) shows great promise for the extraction and esterification of hydrophilic VFAs. In this study, several ILs were evaluated to select a water-immiscible and efficient extraction solvent. The selected IL: trihexyltetradecyl phosphonium dibutylphosphate ([P666,14][DBP]) gave a cumulative VFA extraction of around 842.8 mg/g IL. The predicted excess enthalpy (HE) and logarithmic activity coefficients ln(γ) using the COSMO-RS model were validated with the experimentally obtained VFA recovery from fermentation broth. To understand the extraction mechanism of VFAs, quantum theory of atoms in molecules (QTAIM) and noncovalent interaction (NCI) were performed. The results suggest that long chain fatty acids exhibit strong Van der Waals interaction with DBP anion leading to higher VFA extraction. The enzymatic esterification of VFAs with ethanol in [P666,14][DBP] was optimized using the Box-Behnken response surface design of experiment. Under the optimized conditions, up to 83.7 % of hexanoic acid was converted to ethyl esters, while other shorter chain VFAs has lower conversion efficiency (38.3%-63.2%).","PeriodicalId":74745,"journal":{"name":"RSC sustainability","volume":"75 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142192801","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Activated carbon with composite pore structures made from peanut shell and areca nut fibers as sustainable adsorbent material for the efficient removal of active pharmaceuticals from aqueous media†","authors":"Sujata Mandal, Dayana Stephen and Sreeram Kalarical Janardhanan","doi":"10.1039/D4SU00262H","DOIUrl":"10.1039/D4SU00262H","url":null,"abstract":"<p >The massive growth in the human population, along with an improved healthcare system, resulted in the discharge of a large variety of active pharmaceuticals, including antibiotics, into the water stream leading to genotoxic, mutagenic, and ecotoxicological effects on plants, animals, and human. In this study, cost-effective and environmentally sustainable activated carbon adsorbents with composite pore structures have been prepared from agricultural waste materials, peanut shells and areca nut fibers, through a facile method. Phosphoric acid (H<small>₃</small>PO<small>₄</small>) of two different concentrations (20% and 40%) was used for preparing the activated carbons. All the activated carbon samples showed reasonably high specific surface area (SSA) ranging between 580–780 m<small>²</small> g<small>⁻¹</small>. The SSA of the activated carbon obtained from peanut shells was higher than those obtained from the areca nut fibers. The adsorption characteristics of the prepared activated carbons were assessed for the common active pharmaceuticals, paracetamol, amoxicillin, and aspirin, in an aqueous medium. The rate of adsorption of the activated carbon was very high, and about 90% of the paracetamol was adsorbed within 5 min of contact. The adsorption kinetics followed a pseudo-second-order kinetic model. The paracetamol adsorption capacity of the activated carbons obtained from the Langmuir adsorption isotherm (monolayer) model was 67 mg g<small>⁻¹</small>. Regeneration and reuse of the adsorbent for the removal of paracetamol were also studied for up to 5 cycles. The present research work ensures the “3 Rs” principle [reduce (waste), reuse and recycle] of environmental sustainability.</p>","PeriodicalId":74745,"journal":{"name":"RSC sustainability","volume":" 10","pages":" 3022-3035"},"PeriodicalIF":0.0,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/su/d4su00262h?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142192804","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Eco-friendly synthesis and enhanced antibacterial action of bimetallic Ag/ZnO nanoparticles using Hylocereus costaricensis stem extract","authors":"Joel Xaviour, S. Sreelekshmi, Jebin Joseph, S. Alfiya Fathima and T. Sajini","doi":"10.1039/D4SU00254G","DOIUrl":"10.1039/D4SU00254G","url":null,"abstract":"<p >This work presents a novel method for generating bimetallic silver and zinc oxide nanoparticles (Ag/ZnO-NPs) using <em>Hylocereus costaricensis</em> (HC) stem extract and microwave irradiation. Silver and zinc oxide nanoparticles were prepared separately during the synthesis process, and they were directly mixed to produce bimetallic Ag/ZnO-NPs. A thorough characterisation was conducted utilising various analytical methods to clarify the formed nanoparticles' structural, morphological and constitutional characteristics. The conventional agar well diffusion technique was then used to assess the Ag/ZnO bimetallic nanoparticles' antibacterial activity towards <em>Staphylococcus aureus</em> and <em>Escherichia coli</em>, the two most common human pathogenic bacteria. The characterisation analysis showed the successful synthesis of bimetallic Ag/ZnO-NPs with a cluster-like spherical alloy-type morphology with an average hydrodynamic diameter of 281.7 nm and a direct band gap of 2.90 eV. The antibacterial results revealed that bimetallic Ag/ZnO-NPs have a solid combinatorial antibacterial activity, underscoring their abilities to be effective antibacterial substances from renewable sources. This study opens the door for more in-depth investigation into this topic by enhancing bimetallic nanoparticles and their utilisation in the biomedical field.</p>","PeriodicalId":74745,"journal":{"name":"RSC sustainability","volume":" 10","pages":" 3077-3089"},"PeriodicalIF":0.0,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/su/d4su00254g?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142192802","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ionic liquid-based extraction of metal ions via polymer inclusion membranes: a critical review","authors":"Babafemi Adigun, Bishnu P. Thapaliya, Huimin Luo and Sheng Dai","doi":"10.1039/D4SU00297K","DOIUrl":"10.1039/D4SU00297K","url":null,"abstract":"<p >Polymer Inclusion Membranes (PIMs) have significantly advanced the field of membrane-based separation technologies introducing an innovative method for the selective transport and extraction of metal ions. The incorporation of ionic liquids (ILs) into PIMs leverages the exceptional characteristics of ILs to boost both selectivity and efficiency in the separation of metal ions. This synergy advances metal separation processes towards greener and more sophisticated solutions perfectly aligning with green chemistry and environmental sustainability. This review presents an overview of current knowledge on PIMs including the distinct roles of their different components. It critically assesses the different strategies essential for achieving optimal membrane performance and ensuring stability and selectivity of PIMs. Future research directions are discussed particularly focusing on the understanding of transport dynamics within PIMs and refining membrane compositions to reduce the risk of carrier leakage. These investigations promise to enhance the efficiency and environmental friendliness of metal ion separation propelling the field towards more effective and sustainable practices. This review can serve as a roadmap for ongoing research, promoting the advancement of IL-based extraction of metal ions <em>via</em> PIMs for sustainable and efficient metal separation processes.</p>","PeriodicalId":74745,"journal":{"name":"RSC sustainability","volume":" 10","pages":" 2768-2780"},"PeriodicalIF":0.0,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/su/d4su00297k?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142192806","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sustainability of hydrogen manufacturing: a review","authors":"Satish Vitta","doi":"10.1039/D4SU00420E","DOIUrl":"10.1039/D4SU00420E","url":null,"abstract":"<p >Hydrogen is a highly versatile energy vector, and most importantly, its oxidation, which releases energy, is a green process with no associated emissions. Hence, it is considered a green alternative that can supply energy and simultaneously reduce global warming. This gas, however, does not occur naturally in sufficient quantities and needs to be synthesized using different resources. The two most feasible methods for producing H<small>₂</small> are steam methane reforming and water splitting <em>via</em> electrolysis. Therefore, these two processes were reviewed first, and subsequently, a complete sustainability analysis was performed using currently available data. It has been found that input raw materials such as methane and water will be required in ‘gigatonne’ quantity every year. Although availability of water does not pose supply risk, methane production falls far short of the requirement and becomes a supply risk. The conversion of these into H<small>₂</small> requires energy and results in the production of ‘Gt’ of CO<small>₂</small>. For example, the production of 1 Gt of H<small>₂</small> using the steam methane reforming process requires ∼3.6 EJ of energy and releases ∼10 Gt of CO<small>₂</small>. In contrast, water splitting electrolysis requires ∼198 EJ of energy and releases anywhere from 102 Gt to 220 Gt of CO<small>₂</small>, depending on the electricity generation mix. Additionally, they have ecological impacts in the form of acidification, marine toxicity, particulate emissions and so on, which affect all life forms on the earth. This analysis clearly shows that complete transitioning to H<small>₂</small>-based energy supply is unsustainable and only a fraction of the energy needs can be supplemented.</p>","PeriodicalId":74745,"journal":{"name":"RSC sustainability","volume":" 11","pages":" 3202-3221"},"PeriodicalIF":0.0,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/su/d4su00420e?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142192842","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Upcycled waxes from mixed polyolefins for hot-melt adhesive (HMA) applications†","authors":"Anurag Ganapathi, Mohamed Shaker and Muhammad Rabnawaz","doi":"10.1039/D4SU00135D","DOIUrl":"10.1039/D4SU00135D","url":null,"abstract":"<p >Upcycled waxes are blended with poly(ethylene-<em>co</em>-vinyl acetate) (EVA) to make hot-melt adhesives (HMAs). Herein, we report partially recycled HMAs that were prepared by blending EVA with upcycled waxes obtained from mix waste polyolefins. First, waste mixed polyolefins (such as high-density, low-density, and linear low-density polyethylene and polypropylene) were converted into waxes in high yields reaching up to 92%. The obtained upcycled waxes were used as an additive for HMAs along with gum rosin. The thermal properties and seal strength of the HMAs containing upcycled waxes were compared with those of commercially available HMAs. The HMA made from upcycled wax was found to be as efficient in seal strength as the commercially available HMA. This upcycling of plastic waste for use in HMAs is yet another way of promoting circularity in single-use plastics.</p>","PeriodicalId":74745,"journal":{"name":"RSC sustainability","volume":" 10","pages":" 3047-3053"},"PeriodicalIF":0.0,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/su/d4su00135d?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142192808","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Lab sustainability programs LEAF and My Green Lab®: impact, user experience & suitability†","authors":"Bianca R. Schell and Nico Bruns","doi":"10.1039/D4SU00387J","DOIUrl":"10.1039/D4SU00387J","url":null,"abstract":"<p >Facing the climate crisis and planetary boundaries, research institutions must address the challenge of becoming climate-neutral and using resources more sustainably. Natural science laboratories are the most resource-intensive and CO<small>₂</small>-emitting units within these institutions. Consequently, research groups aim to understand how to lower emissions and become sustainable by participating in green lab programs for wet labs, such as My Green Lab® or LEAF. Here, we compare these programs, analyse their impact on emission savings, and give insights from conducting both programs simultaneously in our biological and chemical labs. As a centrepiece, we provide a quantitative comparison of the programs based on a Germany-wide survey of participants from both programs. We showcase the significant impact of the programs on employees' motivation to work sustainably, highlight the advantages and shortcomings of the programs, and elucidate the pitfalls of greenwashing risks and the risks of leaving the most effective measures unimplemented. Finally, we provide decision-making guidance to help scientists choose the most suitable lab sustainability program based on their individual research backgrounds, needs, and personal preferences.</p>","PeriodicalId":74745,"journal":{"name":"RSC sustainability","volume":" 11","pages":" 3383-3396"},"PeriodicalIF":0.0,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/su/d4su00387j?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142192809","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sustainable micro-cellulosic additives for high-density fiber cement: emphasis on rheo-mechanical properties and cost–performance analysis†","authors":"Sreenath Raghunath, Mahfuzul Hoque, Behzad Zakani, Akash Madhav Gondaliya and E. Johan Foster","doi":"10.1039/D4SU00287C","DOIUrl":"10.1039/D4SU00287C","url":null,"abstract":"<p >To combat climate change (<em>i.e.</em>, global warming), reducing the CO<small>₂</small> footprint of cement-based building materials can be substantiated by incorporating cellulosic fibers into the cement matrix (fiber cement). However, such materials design imposes tremendous technical challenges towards the fabrication process, interlinked to its rheo-mechanical properties. Thus, polycarboxylate-based (petrochemical-derived) rheology modifiers and silica-based (carcinogenic) additives are usually added to the fiber-cement slurry. Micro-cellulosic biomaterials are technically a viable eco-friendly alternative, capable of modifying the rheo-mechanical properties, yet to be explored for high-density (&gt;8 wt% fiber) fiber cement. Herein, we have employed morphologically distinctive alpha-cellulose (AC) and microcrystalline cellulose (MCC) as rheo-mechanical additives. The total content of biomaterials in the fiber cement was up to 12 wt%, where the ratio between the micro-cellulosic additive (AC/MCC) and the cellulosic fibers varied proportionally. As a result, various composites were fabricated based on combinations 1 (AC and fibers) and 2 (MCC and fibers), and their rheo-mechanical properties were characterized to understand the effect of this morphologically distinctive micro-cellulose. Firstly, the rheological analysis revealed that combination 1 reduced the yield stress (improving the workability) at any content – with 4 wt% AC content indicating a maximum reduction in yield stress of 30%. Secondly, flexural strength analysis revealed that combinations 1 and 2 improve the modulus of rupture (MOR), and combination 2 (at 6 wt% MCC content) resulted in a 42% increase in MOR. Finally, we presented the cost-to-performance ratio analysis (economic perspective), highlighting the positive ramifications of this sustainable rheology modifier and additives for the cement-based composite – an avenue for low-embodied carbon building materials without compromising the strength-to-weight ratio.</p>","PeriodicalId":74745,"journal":{"name":"RSC sustainability","volume":" 11","pages":" 3362-3374"},"PeriodicalIF":0.0,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/su/d4su00287c?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142192810","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}