Saihong Cao , Shu Yang , Ying Jin , Hongming Xiang , Haifan Fan , Zakira Tabassum , Kangkang Ou , Kaikai Chen , Binjie Xin
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引用次数: 0
Abstract
The development of high-performance oil-water separation membranes necessitates addressing the inherent challenges of high energy consumption while ensuring both high flux and durability. In this study, we propose an electrospun Janus membrane with an asymmetric structure, consisting of a hydrophilic layer made from polyacrylonitrile (PAN) and polyethylene glycol (PEG), and a hydrophobic layer composed of polycaprolactone (PCL), referred to as the PPCL membrane. By constructing a gradient pore structure within the bilayer membrane, we enhance capillary forces to achieve superior unidirectional water transport. This design allows water droplets to permeate the Janus membrane in just 0.05 s, with a diffusion rate of 217.6 mm2/s and a diffusion area of 1084.9 mm2. The separation efficiency is found to positively correlate with both the diffusion area and rate, while negatively correlating with time, thereby confirming the beneficial effect of unidirectional water transport on oil-water separation. Even after 9 oil-water separation cycles, the PPCL-16 % membrane maintains stable separation efficiencies of 92.5 ± 1.8 % for white mineral oil-water mixtures and 91.3 ± 1.2 % for dichloromethane emulsions, while consistently achieving an oil-in-water emulsion flux exceeding 205 L·m−2·h−1. In summary, this study offers theoretical support for the design and optimization of unidirectional water transport membranes in oil-water separation applications, ensuring low energy consumption while emphasizing high separation flux and efficiency.
期刊介绍:
The Journal of Water Process Engineering aims to publish refereed, high-quality research papers with significant novelty and impact in all areas of the engineering of water and wastewater processing . Papers on advanced and novel treatment processes and technologies are particularly welcome. The Journal considers papers in areas such as nanotechnology and biotechnology applications in water, novel oxidation and separation processes, membrane processes (except those for desalination) , catalytic processes for the removal of water contaminants, sustainable processes, water reuse and recycling, water use and wastewater minimization, integrated/hybrid technology, process modeling of water treatment and novel treatment processes. Submissions on the subject of adsorbents, including standard measurements of adsorption kinetics and equilibrium will only be considered if there is a genuine case for novelty and contribution, for example highly novel, sustainable adsorbents and their use: papers on activated carbon-type materials derived from natural matter, or surfactant-modified clays and related minerals, would not fulfil this criterion. The Journal particularly welcomes contributions involving environmentally, economically and socially sustainable technology for water treatment, including those which are energy-efficient, with minimal or no chemical consumption, and capable of water recycling and reuse that minimizes the direct disposal of wastewater to the aquatic environment. Papers that describe novel ideas for solving issues related to water quality and availability are also welcome, as are those that show the transfer of techniques from other disciplines. The Journal will consider papers dealing with processes for various water matrices including drinking water (except desalination), domestic, urban and industrial wastewaters, in addition to their residues. It is expected that the journal will be of particular relevance to chemical and process engineers working in the field. The Journal welcomes Full Text papers, Short Communications, State-of-the-Art Reviews and Letters to Editors and Case Studies