Xiaozhen Lu, Lin Wang, Xuewu Zhu, Liping Qiu, Zhe Yang, Daliang Xu, Jiashuai Wei, Qianxin Zhang, Chunzhao Chen, Shan Niu, Bin Liu
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引用次数: 0
Abstract
Polyamide (PA) nanofiltration membranes (NFMs) possess highly crosslinked structures, leading to several technical limitations such as poor selectivity, low permeance, and severe fouling. This study devised a novel isopropanol (IPA)-induced decrosslinking strategy to systematically modulate PA crosslinking density by precisely controlling IPA concentration and temperature. IPA induces swelling effects and hydrogen bonding, selectively extracting loosely crosslinked PA chain segments and allowing for network relaxation and rearrangement to form a uniform structure with lower overall crosslinking density. The optimised NF membrane post-treated with IPA at 60°C (NF-IPA@60) achieved 32.94% decrosslinking with enhanced surface negative charge density and enlarged pore size. Compared to the control membrane (NF-H2O), NF-IPA@60 exhibited higher pure water permeance (27.3 LMH/bar) while maintaining 92.7% Na2SO4 rejection. Enhanced Donnan exclusion significantly improved micropollutant removal, particularly for anionic contaminants such as perfluorooctanoic acid and perfluorooctanesulfonic acid. Pearson correlation analysis established clear structure–performance relationships for the decrosslinking strategy. Natural water testing showed that NF-IPA@60 exhibit total organic carbon removal efficiencies exceeding 88.2%, with 3.15-fold improvement in organic/mineral selectivity and excellent antifouling properties. This study provides a novel theoretical framework and technical approach for high-performance NFM design, offering significant potential for overcoming traditional membrane technology bottlenecks.
期刊介绍:
Water Research, along with its open access companion journal Water Research X, serves as a platform for publishing original research papers covering various aspects of the science and technology related to the anthropogenic water cycle, water quality, and its management worldwide. The audience targeted by the journal comprises biologists, chemical engineers, chemists, civil engineers, environmental engineers, limnologists, and microbiologists. The scope of the journal include:
•Treatment processes for water and wastewaters (municipal, agricultural, industrial, and on-site treatment), including resource recovery and residuals management;
•Urban hydrology including sewer systems, stormwater management, and green infrastructure;
•Drinking water treatment and distribution;
•Potable and non-potable water reuse;
•Sanitation, public health, and risk assessment;
•Anaerobic digestion, solid and hazardous waste management, including source characterization and the effects and control of leachates and gaseous emissions;
•Contaminants (chemical, microbial, anthropogenic particles such as nanoparticles or microplastics) and related water quality sensing, monitoring, fate, and assessment;
•Anthropogenic impacts on inland, tidal, coastal and urban waters, focusing on surface and ground waters, and point and non-point sources of pollution;
•Environmental restoration, linked to surface water, groundwater and groundwater remediation;
•Analysis of the interfaces between sediments and water, and between water and atmosphere, focusing specifically on anthropogenic impacts;
•Mathematical modelling, systems analysis, machine learning, and beneficial use of big data related to the anthropogenic water cycle;
•Socio-economic, policy, and regulations studies.