Vacuum membrane distillation to remove ethyl acetate from aqueous solutions

Water pollution of volatile organic compounds (VOCs) was a serious environment problem. Vacuum membrane distillation (VMD) was an environmental friendly membrane separation technology to treat VOCs wastewater. Aqueous binary mixtures of ethyl acetate were treated by VMD process. Comparisons were made between different membrane modules for investigating the influence of channel on the membrane separation performance. Three kinds of channel presented different useful area, shape, width, and depth. The arc flow channel was more easier to reduce resistance than square flow channel. Operation parameters influencing flux and separation performance were examined: feed-flow rate, feed concentration, vacuum degree, and feed temperature. Vacuum degree and feed temperature had more significant influence on membrane flux and separation factor than other parameters. The effect of membrane type on separation properties was also investigated, the smaller pore membrane was better for increasing the separation factor. Three membrane modules with various channels were used for experiments. VMD is very suitable for low concentration of aqueous solution VOC separation and better experimental separation performance could be obtained.