Journal of Environmental Chemical Engineering
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2024
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IF 7.4
Bingke Tian,Chaofeng Huang,Yingshuang Zhang,Cong li,Hongru Jiang,Chongqing Wang,Hui Wang,Shangbo Zhang,Liuchuang Zhao
Plastics are extensively used in packaging, automobiles, sanitation, agriculture, and architecture due to their lightweight, malleability, corrosion resistance, and low cost. However, their short lifespan leads to the rapid accumulation of plastic waste. Therefore, recycling waste plastics is crucial to conserve resources and protect the environment from "white pollution." This study developed a flotation process to facilitate the recycling of common polyesters by separating polyamide (PA), polycarbonate (PC), polyethylene terephthalate (PET), polymethyl methacrylate (PMMA), and polyurethane (PU). The flotation process was based on a hydrophilic gradient induced by modification with methanol, ethanol, and ethanolamine. The floatability sequence of the polyesters was PA < PU < PET < PC < < PMMA in the methanol-based system, PA < PU < PET < < PC ≈ PMMA in the ethanol-based system, and PET < PU < PA < < PC < PMMA in the ethanolamine-based system. The floatability of the polyesters was closely related to the reactivity of ester exchange. Based on the hydrophilic gradients, a cascaded flotation process was designed, following the ester exchange mechanism, to sequentially recover PET, PA, PC, and PMMA. PA, PET, and PU were the sinking plastics after modification with methanol, ethanol, and ethanolamine, respectively, while only PC remained hydrophilic after methanol modification. The purity of PA, PC, PET, and PMMA was 95.10 %, 93.68 %, 89.39 %, and 86.42 %, respectively, with recovery rates of 82.96 %, 83.90 %, 96.08 %, and 100 %. This study presents a promising approach for the flotation separation of waste polyesters.
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2025
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IF 9
Ying-Lin He,Zhuo Chen,Dilibinuer Niyazimaimaiti,Yuan Fan,Rimeh Ismail,Abudukeremu Kadier,Chantaraporn Phalakornkule,Putu Teta Prihartini Aryanti,Ghizlane Achagri,Peng-Cheng Ma
To address global freshwater scarcity, developing a sustainable and efficient brackish/high salinity water desalination technology is crucial. Solar-driven interfacial evaporation (SIE) systems typically consist of a water-absorbing layer drawing water via capillary action to the interface and a photothermal conversion layer absorbing sunlight to heat the interface. Researchers have focused primarily on designing various photothermal materials to enhance heat generation and evaporation efficiency, while they often overlook the need for all-weather functionality, limiting further advancement of SIE systems. This study introduces a novel basalt fabric-based photo-electrothermal interfacial evaporator for all-weather efficient desalination, integrating photothermal and electrothermal effects to enhance evaporation rates and reduce reliance on sunlight. The basalt fabric is functionalized with polydopamine, carbon nanotubes, and polypyrrole to improve its photothermal properties, and stainless steel mesh 304 is used as an electrothermal layer. Under simulated sunlight (1 sun) and 1.5 V in the laboratory, the evaporation rate of actual brackish water can reach 4.43 kg m −2 h −1 ; under real sunlight and 1.5 V outdoors, the evaporation rate can reach up to 6.37 kg m −2 h −1 . Additionally, due to the well-designed multilayer structure with Janus hydrophilicity gradient distribution, the evaporator exhibits excellent salt resistance and long-term stability, maintaining a daytime evaporation rate above 2.17 kg m −2 h −1 during 120-hour continuous operation without any intervention. The purified water meets the drinking water standards set by the WHO, with significant reductions in ion concentrations and chemical oxygen demand. This study provides a promising approach for efficient and sustainable brackish water purification, offering potential applications in water-scarce regions.
研究领域:
环境科学
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材料工程
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海水淡化
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可再生能源
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可持续技术
✓ 已验证
产品关联
DOI
高影响因子