RSC sustainability最新文献

Critical metal recovery from e-waste in concentrated ionic media using ultrasound†

RSC sustainability Pub Date : 2025-03-12 DOI: 10.1039/D4SU00715H

Christopher E. Elgar, Kelsey Hall and Andrew P. Abbott

{"title":"Critical metal recovery from e-waste in concentrated ionic media using ultrasound†","authors":"Christopher E. Elgar, Kelsey Hall and Andrew P. Abbott","doi":"10.1039/D4SU00715H","DOIUrl":"https://doi.org/10.1039/D4SU00715H","url":null,"abstract":"With an increase in the amount of e-waste being generated worldwide, there is greater demand for sustainable recycling techniques to recover components and technology critical metals (TCMs) that would otherwise be discarded. Current methods for solder removal are inefficient, produce harmful gases and by-products. This work aims to use catalytic etchants in concentrated ionic media, to improve the sustainability of recycling techniques. The viscosity of these solutions is often perceived as a limiting factor for ion mobility, so ultrasonic agitation has been used to improve mass transport. Cyclic voltammetry and linear sweep voltammetry have been used to investigate the redox behaviour of tin and lead in solder, and how ultrasound can overcome passivation and improve the dissolution of these metals. Ultrasound results in a linear response between the slope of the LSV and solution conductivity for tin, suggesting a migration-controlled mechanism, however passivation still occurred with lead, showing that there is still some diffusion control. A waste printed circuit board was etched using FeCl3 catalyst in a choline chloride and ethylene glycol DES (ChCl : 2EG) but no major components were removed after 30 minutes of sonication at room temperature. The use of a choline chloride and water in a 1 : 10 molar ratio removed most of the components, along with some gold coating, under the same conditions. The additional water content in the brine improved the fluidity of the solution, enabling dissolution of the solder and copper under-layer, freeing the gold. Cavitation effects including acoustic streaming and jetting work in tandem to aid metal removal.","PeriodicalId":74745,"journal":{"name":"RSC sustainability","volume":" 4","pages":" 1957-1965"},"PeriodicalIF":0.0,"publicationDate":"2025-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2025/su/d4su00715h?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143761608","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}

引用次数: 0

Catalyst coated membranes for fuel cell and water electrolyser delamination induced by organic solution soaking and water ultrasonication†

RSC sustainability Pub Date : 2025-03-10 DOI: 10.1039/D4SU00795F

Tanongsak Yingnakorn, Jennifer Hartley, Molly E. Keal, Ross Gordon, Daniel Marin Florido, Andrew P. Abbott and Jake M. Yang

{"title":"Catalyst coated membranes for fuel cell and water electrolyser delamination induced by organic solution soaking and water ultrasonication†","authors":"Tanongsak Yingnakorn, Jennifer Hartley, Molly E. Keal, Ross Gordon, Daniel Marin Florido, Andrew P. Abbott and Jake M. Yang","doi":"10.1039/D4SU00795F","DOIUrl":"https://doi.org/10.1039/D4SU00795F","url":null,"abstract":"This study presents a novel room-temperature, two-step process for separating catalyst-coated membranes (CCMs) used in fuel cells and water electrolysers. The method not only achieves a clean separation of the central membrane from the catalyst materials but also preserves the catalyst, thereby avoiding any potential hazardous gas release. The process involves a brief one-minute soak in an optimised solution, followed by a 10–12 minutes low-power ultrasonic treatment in water. The effectiveness of various organic (acetone, ethanol, ethylene glycol, hexane, and toluene) and aqueous (CaCl2, HCl, NaOH, NH4Cl) soaking solutions was thoroughly investigated to identify the optimal conditions for achieving near-pristine, separated membranes. This safe and efficient approach offers a promising strategy for CCM recycling, promoting resource recovery and economic benefits in clean energy technologies.","PeriodicalId":74745,"journal":{"name":"RSC sustainability","volume":" 4","pages":" 1900-1908"},"PeriodicalIF":0.0,"publicationDate":"2025-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2025/su/d4su00795f?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143761598","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}

引用次数: 0

Production of oxymethylene ethers (OME) as sustainable diesel fuel substitutes: continuous synthesis from dimethyl ether and trioxane and evaluation of catalyst stability†

RSC sustainability Pub Date : 2025-03-10 DOI: 10.1039/D4SU00818A

Marius Drexler, Victor Zaghini Francesconi, Ulrich Arnold, Thomas A. Zevaco and Jörg Sauer

{"title":"Production of oxymethylene ethers (OME) as sustainable diesel fuel substitutes: continuous synthesis from dimethyl ether and trioxane and evaluation of catalyst stability†","authors":"Marius Drexler, Victor Zaghini Francesconi, Ulrich Arnold, Thomas A. Zevaco and Jörg Sauer","doi":"10.1039/D4SU00818A","DOIUrl":"https://doi.org/10.1039/D4SU00818A","url":null,"abstract":"Oxymethylene ethers (OMEs) are currently being investigated as attractive substitutes for fossil diesel fuel. In particular, the properties of OMEs containing 3–5 formaldehyde units (CH3O(CH2O)nCH3 with n = 3–5) are similar and mostly compliant with current diesel specifications. With their production based on renewable methanol, OMEs can contribute significantly to a future sustainable mobility. This study elaborates an anhydrous, liquid phase OME synthesis based on dimethyl ether (DME). Using a newly designed continuous production plant, the performance of extruded zeolite catalysts based on a commercially available ZSM-5 material is evaluated. The characteristics of the produced catalysts are analyzed extensively and discussed. Comprehensive characterization of the spent catalyst as well as regeneration experiments were performed to investigate catalyst deactivation mechanisms. It was shown that deactivation mechanisms are similar to those observed in methanol-to-hydrocarbon processes. Thus, understanding of these aspects is improved and approaches for further optimization can be identified.","PeriodicalId":74745,"journal":{"name":"RSC sustainability","volume":" 4","pages":" 1941-1956"},"PeriodicalIF":0.0,"publicationDate":"2025-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2025/su/d4su00818a?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143761602","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}

引用次数: 0

Cannabis sativa biochar: characterization and preliminary application in plant growth and adsorption, and as an electrode material†

RSC sustainability Pub Date : 2025-03-04 DOI: 10.1039/D4SU00829D

Maria Belen Ceretta, Sofia Antic Gorrazzi, Sebastian D’Ippolito, Julieta Mendieta, Debora Nercessian and Sebastian Bonanni

引用次数: 0

An aqua regia-free chemical recovery and reprecipitation of Ir from IrOx catalysts: optimisation of the extraction efficiency using surface response methodology†

RSC sustainability Pub Date : 2025-03-03 DOI: 10.1039/D5SU00038F

Sarah Turnbull, Delphine Clauss, Vincent Martin, Jean-Pierre Magnin, Laetitia Dubau and Frédéric Maillard

{"title":"An aqua regia-free chemical recovery and reprecipitation of Ir from IrOx catalysts: optimisation of the extraction efficiency using surface response methodology†","authors":"Sarah Turnbull, Delphine Clauss, Vincent Martin, Jean-Pierre Magnin, Laetitia Dubau and Frédéric Maillard","doi":"10.1039/D5SU00038F","DOIUrl":"https://doi.org/10.1039/D5SU00038F","url":null,"abstract":"The widespread deployment of hydrogen is essential in the energy transition away from fossil fuels. There is an increasing demand for iridium (Ir) in the proton-exchange membrane water electrolysis (PEMWE) industry, acting as the catalyst for the oxygen evolution reaction (OER). However, Ir is one of the rarest platinum group metals (PGMs) and its recycling requires significant energy and has considerable environmental impacts. Therefore, developing an innovative energy-efficient recycling method is essential to enhance the use of Ir. This study focuses on the development of a microwave-assisted leaching protocol of Ir from a commercial iridium oxide (IrOx) catalyst and its reprecipitation in the form of a salt. A Box–Behnken optimisation of the Ir leaching efficiency was performed by varying the temperature (70–200 °C), chloride concentration ([Cl−]) (0–4 M) and hydrogen peroxide concentration ([H2O2]) (0–3% v/v). An optimum of 91% extraction efficiency was predicted and then confirmed experimentally, achieving an Ir leaching efficiency of 83 ± 10%, which corresponds to an Ir mass extraction of 769 mgIr gIrOx−1. The precipitation of the Ir leachate solution was then performed to obtain Ir in the form of ammonium hexachloroiridate ((NH4)2IrCl6) with 94.6% purity.","PeriodicalId":74745,"journal":{"name":"RSC sustainability","volume":" 4","pages":" 1741-1750"},"PeriodicalIF":0.0,"publicationDate":"2025-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2025/su/d5su00038f?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143761628","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}

引用次数: 0

Microplastics in the rough: using data augmentation to identify plastics contaminated by water and plant matter†

RSC sustainability Pub Date : 2025-02-27 DOI: 10.1039/D4SU00612G

Joseph C. Shirley, Kobiny Antony Rex, Hassan Iqbal, Christian G. Claudel and Carlos R. Baiz

{"title":"Microplastics in the rough: using data augmentation to identify plastics contaminated by water and plant matter†","authors":"Joseph C. Shirley, Kobiny Antony Rex, Hassan Iqbal, Christian G. Claudel and Carlos R. Baiz","doi":"10.1039/D4SU00612G","DOIUrl":"https://doi.org/10.1039/D4SU00612G","url":null,"abstract":"Microplastics are present in nearly all environments. The detection of microplastics in the field is an important step toward understanding and regulating the proliferation of plastic waste, particularly in natural environments. Real-time surveys require robust instruments, rapid acquisition, and minimal processing. Near infrared (NIR) spectroscopy is an ideal technique to detect polymer composition regardless of spectral interference by water and/or organic matter. Here we report a fiber-based NIR instrument designed for simple and efficient spectral acquisition of consumer plastic particles across a range of sizes. Data augmentation with measured interferent spectra has been used to generate machine-learning based classification models that can identify polymer compositions in plastic particles that are wet and/or mixed in with organic plant material. These models achieve 98.5% accuracy on synthetic data and 86.4% accuracy when transferred to spectra of plastic particles of nine common polymers with particle sizes as small as 500 μm. Our model paves the way for the development of equipment to perform real-time surveys of microplastic compositions in the field.","PeriodicalId":74745,"journal":{"name":"RSC sustainability","volume":" 4","pages":" 1886-1899"},"PeriodicalIF":0.0,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2025/su/d4su00612g?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143761597","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}

引用次数: 0

Vortex fluidic-mediated transesterification enhancement of mongongo fatty acid ethyl ester production for haircare applications†

RSC sustainability Pub Date : 2025-02-26 DOI: 10.1039/D4SU00763H

Xuejiao Cao, Xuan Luo, Safira M. Barros, Wenjin Xing, Melanie MacGregor, Iliana Delcheva, Jonathan A. Campbell, Shan He, Bradley P. Kirk, Youhong Tang and Colin L. Raston

{"title":"Vortex fluidic-mediated transesterification enhancement of mongongo fatty acid ethyl ester production for haircare applications†","authors":"Xuejiao Cao, Xuan Luo, Safira M. Barros, Wenjin Xing, Melanie MacGregor, Iliana Delcheva, Jonathan A. Campbell, Shan He, Bradley P. Kirk, Youhong Tang and Colin L. Raston","doi":"10.1039/D4SU00763H","DOIUrl":"https://doi.org/10.1039/D4SU00763H","url":null,"abstract":"Fatty acid ethyl esters (FAEE) are one of the most popular ingredients in the organic cosmetic market due to their versatile functionality. However, its production technique aligning with the principle of green chemistry and adhering to organic standards remains unexplored. This study investigated the use of the vortex fluidic device (VFD), a versatile thin-film processing device that can generate substantial mechanical energy within a rapidly rotating tube, to assist in the sustainable and efficient production of Mongongo FAEE. Using the VFD, a FAEE yield of 92.65% was achieved within 20 minutes of processing, 1.3 times more effective than that attained via bench-top methods. Proton nuclear magnetic resonance (1H NMR) and gas chromatography-mass spectrometry (GC-MS) confirmed the preservation and elevated concentrations of polyunsaturated FAEE following VFD processing. Furthermore, Mongongo FAEE was investigated for its application in hair protection. In a custom hair styling simulation experiment, a comparative analysis of Mongongo oil with FAEE demonstrated that Mongongo FAEE exhibited superior coverage efficiency on the hair surface, masking 95% of sulphur and nitrogen from the hair surface. This results in reduction in pore size, improved surface integrity, enhanced gloss, and minimised cysteine oxidation of hair. In the sun protection test, the FAEE-treated hair demonstrates a uniform morphology after 8 hours of sunlight exposure. Overall, it has been shown that a high yield of Mongongo FAEE was effectively achieved via VFD processing, while also demonstrating the ability to use the product in haircare applications.","PeriodicalId":74745,"journal":{"name":"RSC sustainability","volume":" 4","pages":" 1909-1922"},"PeriodicalIF":0.0,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2025/su/d4su00763h?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143761599","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}

引用次数: 0

A high-performance nanofiltration membrane synthesized by embedding amino acids and ionic liquids in cellulose acetate for heavy metal separation

RSC sustainability Pub Date : 2025-02-26 DOI: 10.1039/D4SU00688G

D. Teja Nayak, Vinoth Kumar Raja, G. Arthanareeswaran, Tran Dang Khoa and Wirach Taweepreda

{"title":"A high-performance nanofiltration membrane synthesized by embedding amino acids and ionic liquids in cellulose acetate for heavy metal separation","authors":"D. Teja Nayak, Vinoth Kumar Raja, G. Arthanareeswaran, Tran Dang Khoa and Wirach Taweepreda","doi":"10.1039/D4SU00688G","DOIUrl":"https://doi.org/10.1039/D4SU00688G","url":null,"abstract":"Water reclamation is necessary to meet the potable water demand. Heavy metals such as iron, zinc, lead, and copper, particularly in water, pose significant toxicity risks to humans and other biological life. Over the last few years, the contamination level of these heavy metals in water and soils has increased alarmingly. Correspondingly, membrane systems have emerged as a prominent approach to water reclamation. In this study, cellulose acetate (CA) membranes incorporating amino acids (AAs) and ionic liquids (ILs) were fabricated using phase inversion technique and effectively utilized for metal separation. The characterizations of these membranes using FTIR, SEM, TGA, and DSC revealed the presence of various functional groups, changes in surface morphologies, and improvements in thermal stabilities due to AA–IL. The pure water flux (PWF) was increased to 98 L m−2 h−1 at 4 bar pressure owing to the enhancement of hydrophilicity. The rejection percentage of heavy metal ions for AA–IL (0.5%) incorporated CA membranes was 94%. The rejection rates for ions of the heavy metals copper, zinc, iron, and lead present in the industrial effluent were studied and found to be 89%, 91%, 84%, and 90%, respectively. The rejection capacity of the AA–IL (0.5) incorporated CA membrane was the highest for all the metals. The AA–IL incorporated CA membranes are efficient and effective for nanofiltration to treat heavy metal ion solutions.","PeriodicalId":74745,"journal":{"name":"RSC sustainability","volume":" 4","pages":" 1966-1981"},"PeriodicalIF":0.0,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2025/su/d4su00688g?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143761609","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}

引用次数: 0

Polyhydroxyalkanoate (PHA) production by thermophilic Caldimonas thermodepolymerans comb. nov. from xylan†

RSC sustainability Pub Date : 2025-02-26 DOI: 10.1039/D5SU00040H

Wen Zhou, Salvador Bertrán Llorens, Peter J. Deuss, Gert-Jan W. Euverink and Janneke Krooneman

引用次数: 0

Preparation of thermally curable materials using lignin extracted from sawmill co-product†

RSC sustainability Pub Date : 2025-02-25 DOI: 10.1039/D4SU00767K

Libby J. Marshall, Daniel J. Cheney, Jasmine A. Keith, Christopher Kelly, Frédéric Blanc, Andrew J. West and Dave J. Adams

{"title":"Preparation of thermally curable materials using lignin extracted from sawmill co-product†","authors":"Libby J. Marshall, Daniel J. Cheney, Jasmine A. Keith, Christopher Kelly, Frédéric Blanc, Andrew J. West and Dave J. Adams","doi":"10.1039/D4SU00767K","DOIUrl":"https://doi.org/10.1039/D4SU00767K","url":null,"abstract":"We have exemplified the chemical reactivity of a new commercially available organosolv-like lignin via reaction with various amines to form benzoxazine groups. The resulting benzoxazine-modified lignin has desirable thermal properties, making it an attractive alternative to non-renewable benzoxazine resins. The thermal properties of the lignin-benzoxazine products can be altered by increasing the number of benzoxazine groups within the lignin. This is achieved by increasing the number of unsubstituted phenol groups in the lignin prior to benzoxazine formation, thereby increasing the number of benzoxazine groups added to the lignin. We were ultimately able to form a curable system from phenolated lignin prepared from lignin extracted from low-value biomass using ultrasonic biorefinery technology via functionalisation with benzoxazine groups. The properties of the new lignin-based benzoxazines are compared to those of Kraft lignin (obtained from pulp) modified by the same chemical reactions.","PeriodicalId":74745,"journal":{"name":"RSC sustainability","volume":" 4","pages":" 1870-1885"},"PeriodicalIF":0.0,"publicationDate":"2025-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2025/su/d4su00767k?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143761596","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}

引用次数: 0