Chinese Journal of Environmental Engineering•2026•DOI: 10.12030/j.cjee.202507110
Algal-derived taste and odor compounds (2-methylisoborneol, 2-MIB, and geosmin, GSM) in drinking water sources are poorly removed by conventional treatment. This study systematically evaluated the standalone and combined performance of ozone micro-nano bubbles (O3-MNBs) oxidation and powdered activated carbon (PAC) adsorption for removing 2-MIB, GSM, and algal cells from source water. Results showed that O3-MNBs pre-oxidation achieved >97.5% removal of odorants at 400 ng·L−1 and 67.2% algal cell removal within 30 min. When applied as a deep treatment stage, the degradation rate constant (k) was 10.1%–25.6% higher than in pre-oxidation due to lower background matrix interference. Both pre-oxidation and deep treatment reduced effluent concentrations of 2-MIB and GSM to below 10 ng·L−1, with oxidation kinetics fitting pseudo-first-order models (R²>0.95). PAC adsorption of both compounds followed pseudo-second-order kinetics (R²>0.99), with GSM equilibrium adsorption capacity approximately 20.0% higher than that of 2-MIB. In pure water, adsorption capacity increased by >10.0% compared to raw water. Based on kinetic models, a quantitative prediction method was established for O3-MNBs oxidation and PAC adsorption processes, aiming to achieve efficient odorant removal and cost optimization, providing theoretical support for advanced drinking water purification and smart water plant construction.
Chinese Journal of Environmental Engineering•2026•DOI: 10.12030/j.cjee.202507058
With the rapid development of China's lithium-ion power battery industry, the recycling of large-scale retired batteries has become a critical link for the sustainable development of the new energy vehicle industry. The recovery of cathode materials from spent lithium iron phosphate (LiFePO4) batteries is a current research hotspot, significant for resource recycling and environmental protection. This study systematically reviews recent progress in recycling technologies for spent LiFePO4 cathode materials, mainly including direct regeneration, pyrometallurgy, and hydrometallurgy. It focuses on analyzing the current research status of key steps in hydrometallurgy, such as leaching of valuable elements, deep removal of impurities, and product regeneration, and compares the advantages and limitations of various methods. Addressing core issues in current recovery processes, such as insufficient high-value utilization of iron and phosphorus resources and difficulty in deep impurity removal, this study proposes corresponding solutions and technical prospects, aiming to provide theoretical reference and engineering guidance for efficient, clean, and high-value recycling of spent LiFePO4 batteries.
Environmental Chemistry•2026•DOI: 10.7524/j.issn.0254-6108.2025091801
Conventional wastewater treatment technologies face persistent challenges including incomplete removal of emerging contaminants, secondary pollution, and low energy efficiency. Micro-nano robots (MNRs), leveraging their self-propulsion, precise navigation, and high specific surface area, offer a transformative approach for targeted pollutant sequestration and degradation. This review systematically examines the operational mechanisms and propulsion strategies of MNRs in wastewater remediation. Through a data-driven bibliometric analysis, we identify chemical propulsion and photocatalytic degradation as the predominant research foci. We critically evaluate the performance of various MNR designs—including chemically driven, magnetically driven, and light-driven systems—for the removal of organic pollutants, heavy metals, microplastics, radioactive nuclides, and pathogenic microorganisms. Representative studies demonstrate removal efficiencies exceeding 90% for specific contaminants, such as uranium preconcentration via metal-organic framework-based microrobots and microplastic removal using self-driven magnetorobots. Despite these advances, MNRs face intrinsic trade-offs between propulsion efficiency and environmental compatibility, as well as challenges in coordinating actuation and control in complex aqueous matrices. We propose future directions emphasizing sustainable energy-harvesting systems and intelligent, reconfigurable multifunctional designs. This review provides a systematic framework and forward-looking perspective to accelerate the translation of MNR technology from laboratory innovation to practical wastewater treatment applications.
Chinese Journal of Environmental Engineering•2026•DOI: 10.12030/j.cjee.202510042
Given China's escalating municipal solid waste (MSW) generation and the limitations of current classification schemes, this study proposes a novel waste classification model centered on mid-end intelligent sorting technology. The approach integrates targeted pretreatment with multimodal visual recognition and robotic grasping to efficiently sort complex household waste, while compact equipment innovations adapt to the low-value characteristics of recyclables. An engineering demonstration case shows that the technology can effectively recover low-value recyclables comprising 15%–30% of mixed MSW. If applied at 5% of a case city's waste transfer stations, approximately 5×10^4 t of recyclables could be sorted annually. Preliminary estimates indicate a 20% return on investment for operators at an 80 t·d−1 scale. The study demonstrates that mid-end intelligent sorting offers a technically feasible and economically sustainable solution to reduce fiscal expenditure on waste classification while improving efficiency.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-026-4147-9
Fiber-shaped zinc-air batteries (FZABs) with aqueous electrolytes combine intrinsic safety, high energy density (1086 Wh kg−1), and environmental compatibility, making them attractive for wearable applications. However, free water in the electrolyte induces severe anode degradation while being a critical reactant for cathode redox, presenting a dilemma between anode stability and cathode functionality. The semi-open structure of FZABs allows airborne water to permeate and migrate to the anode, causing interfacial instability, while high surface area accelerates solvent evaporation, leading to increased internal resistance and salt crystallization. Consequently, typical cycle life is limited to <50 h. To overcome these challenges, we report a polymer electrolyte that captures atmospheric water as a solvent through the semi-open structure, achieved by introducing acetamide (AA), identified via unsupervised clustering algorithms, into the poly(vinylidene fluoride-hexafluoropropylene)/zinc trifluoromethanesulfonate (PVDF-HFP/Zn(OTf)2) system. AA incorporation preserves solvent-retention capability while reconstructing the Zn2+ coordination structure, promoting salt dissociation and polymer-segment mobility. Low adsorption energy of AA on zinc surfaces suppresses parasitic reactions from ambient moisture, and preferential adsorption across zinc crystal planes directs Zn2+ deposition along the (002) face, leading to uniform plating morphology. The exogenous aqueous polymer electrolyte exhibits superior mechanical properties, enabling stable output even after compression by a 1.7-t vehicle. As proof-of-concept, FZABs integrated with fiber solar cells and sensors in clothing enabled real-time health monitoring and sustainable energy utilization, demonstrating promising practical applications.