RSC sustainability最新文献

Solar-driven interfacial water evaporation is a promising sustainable desalination strategy, but most research has been predominantly focused on material innovation and evaporation rate enhancement, while little attention has been paid to the impact of convective airflow on salt resistance and energy efficiency. Herein, a novel biomass-derived porous evaporator based on carbonized wild rice root (CWRR) with interconnected microchannels was fabricated. The obtained CWRR-based evaporator exhibited remarkable salt tolerance, with a stable evaporation rate of 1.12 kg m⁻² h⁻¹ in 10 wt% NaCl solution over 6 h at efficiencies reaching 82.1%. The addition of convective airflow further enhanced the evaporation performance in 3.5 wt% NaCl at 2 m s⁻¹ wind speed to yield a sustained evaporation rate of 2.19 kg m⁻² h⁻¹ over 6 h at efficiencies reaching 94.3%, highlighting remarkable energy utilization. Further analysis of the data revealed that moderate airflows could optimize vapor diffusion while improving salt deposition, and excessive wind velocities could disrupt the evaporation balance state, thereby accumulating salt and declining efficiency. Overall, solar desalination can be optimized by combining environmental airflow control with sustainable biomass materials as a promising novel strategy for future advanced desalination devices.

Plastic waste presents a critical environmental challenge, with reports of global production surpassing 390 million tons annually and an effective recycling rate of less than 10%. This study investigates advanced recycling methodologies aimed at mitigating plastic waste and promoting a circular economy. Mechanical, chemical, and emerging advanced recycling technologies are evaluated based on efficiency, scalability, and environmental impact. Mechanical recycling achieves material recovery rates up to 60%, accompanied by a 30% reduction in greenhouse gas emissions compared to virgin plastic production; however, polymer contamination and degradation restrict its long-term effectiveness. Chemical recycling processes, including microwave-assisted pyrolysis and enzymatic plastic depolymerization, demonstrate recovery efficiencies exceeding 90%, producing high-quality feedstocks suitable for industrial reuse. Life-cycle assessments reveal that chemical recycling can reduce environmental footprints by approximately 45% relative to conventional disposal practices. Advanced recycling technologies, such as enzymatic and catalytic hydrocracking, blockchain-enabled plastic waste tracking, and bioplastic waste valorization conversion, exhibit conversion efficiencies ranging from 85 to 95%, though scalability remains limited by economic and technological constraints. Integration with digital innovations, such as AI-enabled waste sorting and blockchain-based supply chain transparency, enhances material recovery rates by up to 20%. Policy instruments, notably extended producer responsibility (EPR) schemes and consumer engagement initiatives, further reinforce recycling outcomes. Case studies from Europe and Asia demonstrate landfill diversion rates reaching 75%, underscoring the effectiveness of integrated approaches. The analysis highlights the urgent necessity for multifaceted recycling strategies to curb the escalating plastic waste crisis and facilitate a transition toward a sustainable circular economy. Through the strategic application of technological advancements and policy interventions, it is feasible to achieve a 50% reduction in global plastic waste by 2030, thereby contributing significantly to environmental protection and resource conservation, while mitigating climate change impacts.

Climate change is a critical global concern, driven in part by the continuous increase in greenhouse gas (GHG) emissions. The refrigeration and air conditioning industries significantly contribute to these emissions through the use of hydrofluorocarbons (HFCs), which are potent GHGs. This study evaluates the environmental impacts of natural and fourth-generation synthetic refrigerants to support the development of a sustainable cooling action plan for India. Focusing on low global warming potential (GWP) refrigerant blends, the study investigates the atmospheric oxidation pathways of HFOs—R1234yf, R1234ze(Z), R1234ze(E), and R1243yf—alongside propane, identifying a 90 : 10 propane–R1234yf blend as a promising alternative to R32 in residential split air conditioners up to 7 kW. Thermodynamic analysis reveals that this blend achieves a 15% improvement in both volumetric cooling capacity and coefficient of performance compared with R32 while significantly lowering GWP to the level of R1234yf. Environmental and economic assessments show that the blend emits approximately 5.1 tCO₂e annually, which is 22 times lesser than R32, and offers cost benefits due to its reduced capital and environmental expenditures. The total environmental impact metric for the simulated blend indicates that CO₂-equivalent emissions can be reduced up to 96% when R32 is replaced with the R1234yf + propane blend. Based on these findings, this study proposes key policy imperatives for accelerating the adoption of natural refrigerants in India, in alignment with the Kigali Amendment's HFC phasedown schedule.

This investigation assesses electrochromic windows as a novel green alternative to traditional double-pane windows through a life cycle assessment, which analyzes and compares both types of windows. The life cycle assessment was conducted using the impact categories of TRACI 2.1 in the SimaPro 9.1 application, with ecoinvent, and 1 m² of each window type as the functional unit for the comparisons. The manufacturing of EC windows yielded a total CO₂ generation of 49.6 kg CO₂, and the manufacturing of double-pane windows resulted in 76.05 kg CO₂. In the manufacturing of electrochromic glass windows, the float glass production process contributed 9.79 kg of CO₂ at that stage of fabrication. From the sensitivity analysis, it was determined that using 10% less electricity during electrochromic window production can lower carbon emissions for electrochromic windows by 1.51 kg CO₂. These life cycle assessment impact results were later used for advanced AI-predictive modeling using Python's scientific ecosystem, including PyTorch for neural network implementation, scikit-learn for data preprocessing and metric calculation, and custom-built hierarchical architectures to develop both Artificial Neural Network and Adaptive Neuro-Fuzzy Inference System models. Considering that 200 m² of double-pane windows were replaced by electrochromic windows, the embodied impact of electrochromic window production would be offset by the operational impact of 30.1 t CO₂ in 10.5 months. Since the lifespans of both window types are similar, electrochromic windows are promising green alternatives to double-pane windows.

This report provides a brief synopsis of the inaugural International Conference on Sustainable Chemistry for Net Zero (ICSC-NZ), held at the University of St Andrews in June 2025.

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Green synthesis of efficient photocatalysts using agricultural waste is a promising approach toward sustainable wastewater treatment. In this work, magnetite (Fe₃O₄) and jarosite (KFe₃(SO₄)₂(OH)₆) nanoparticles were synthesized using banana peel extract as a natural reducing/stabilizing agent and potassium source under microwave-assisted conditions. The structural, optical, and magnetic properties of the nanoparticles were systematically characterized. Photocatalytic performance was evaluated for Rhodamine B (RhB) degradation under simulated sunlight irradiation, and reaction kinetics were analyzed using pseudo-first-order models. Jarosite exhibited a rate constant (k) of 0.0198 min⁻¹, approximately double that of magnetite (k = 0.0098 min⁻¹), achieving >99% RhB removal within 30 minutes. Mechanistic studies, including scavenger tests and photoluminescence analysis, confirmed the dominant role of ˙OH radicals and efficient charge separation in jarosite. The catalyst retained >94% activity over five cycles, and total organic carbon (TOC) removal reached 92%, indicating effective mineralization. This study demonstrates a low-cost, scalable, and environmentally friendly route for synthesizing iron-based photocatalysts, aligning with the UN Sustainable Development Goals (SDGs) for clean water and responsible consumption.

Recovering cathode-active materials (CAMs) from end-of-life lithium-ion batteries without added heat or chemicals is pivotal for low-impact, closed-loop manufacturing. We show that circuit capacitance dictates whether a single electrical pulse yields clean, solvent-free delamination or destructive pulverization. Commercial Li(Ni₀.₃₃Mn₀.₃₃Co₀.₃₃)O₂ coated on aluminum foil was exposed to 375–475 J discharges from 6.4 μF (low-C) and 400 μF (high-C) capacitor banks. The low-C circuit squeezed the stored energy into sub-200 μs current spikes (≈15 kA) that heated the CAM/Al interface from ambient to ≈500 K within 100 μs, generating transient stresses of tens of MPa before the foil was severed. A 425 J pulse cleanly lifted the entire coating (99.9 wt% CAMs), leaving only 0.3 wt% residual aluminum, and X-ray diffraction confirmed that the layered oxide structure remained intact. Conversely, the high-C circuit stretched the same energy over > 500 μs, diverting the current into the plasma and fragmenting both the foil and coating. The delamination plateaued near 90 wt%, and at 475 J, aluminum contamination surged nine-fold. One-dimensional transient heat-rise analysis corroborated that temporal energy concentration—enabled by low capacitance—triggers the instantaneous interfacial heating required for clean separation, whereas energy dispersion channels power into fragmentation. This heat- and solvent-free pre-treatment supplies battery-grade layered oxides ready for direct cathode recycling, eliminating the furnaces, acids, and wastewater typical of pyro- or hydrometallurgical routes.

Biomass presents a sustainable alternative to fossil fuels; however, it faces limitations such as high moisture content, low bulk density, and poor grindability. This study investigates the pyrolysis of waste orange peels to produce pyro-char, pyro-oil, and pyro-gas, a process that has been rarely reported in the literature. The effects of pyrolysis temperature, feedstock mass, and heating rate on the yield of these pyro-products were systematically investigated. The biomass was characterized using proximate analysis and thermogravimetric analysis (TGA), while the pyro-products were analyzed for their higher heating value (HHV), lower heating value (LHV), morphology and elemental composition via scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDX), and chemical composition using gas chromatography mass spectrometry (GC-MS). Critical parameters influencing the pyrolysis outcomes were identified: feedstock mass (1–3 kg), temperature (573–1173 K), and heating rate (10–30 K min⁻¹). Under optimal conditions of 2 kg feedstock mass, 873 K temperature, and a heating rate of 20 K min⁻¹, the theoretical yields were 26.52 wt% pyro-char, 22.76 wt% pyro-oil, and 50.72 wt% pyro-gas, with an overall process desirability of approximately 0.7. Experimental yields showed slight deviations, resulting in 28.12 wt% pyro-char, 22.89 wt% pyro-oil, and 48.99 wt% pyro-gas, all within a ±5.7% margin of the theoretical values. The estimated payback period for the initial investment is 1.3 years at a 10% discount rate, which is considerably shorter than the previously reported 6-year period for pyro-gas and pyro-oil production. Scale-up to larger plants is expected to further reduce this duration. This study bridges the gap in comprehensive techno-economic analyses of industrial-scale waste orange peel pyrolysis by producing pyro-char, pyro-oil, and pyro-gas, a three-product yield not previously reported. It offers a sustainable approach to valorizing orange peel waste into high-value products, aligning with Industry 5.0 principles and the United Nations 2030 Sustainable Development Goals.

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