摘要
通过静态浸泡实验考察了臭氧对聚醚砜(PES)和聚偏氟乙烯(PVDF)超滤膜透水能力、截留性能、力学性能等的影响,分析了与臭氧接触前后膜化学组成和性质的变化,结果表明,室温(20±1)℃下与饱和臭氧水接触2h后,PES膜的透水率增大至原始膜的3倍以上,对腐殖酸(HA)的截留率降至0左右,结合膜表面组成和性质分析,臭氧在氧化亲水添加剂聚乙烯吡咯烷酮(PVP)的同时使PES分子也发生了分解,破坏了PES分离层的结构和功能;对于PVDF膜,与饱和臭氧水接触1h后膜的透水率增大至原始膜的1.4倍左右,对HA截留率由原始膜的61.13%降至41.24%,但与臭氧接触时间进一步延长时膜性能无进一步下降,对膜表面组成和性质的分析表明臭氧对PVDF膜分离层的损伤主要是由于PVP的氧化和流失造成的,PVDF本身未发生分解.PVDF膜分离层对臭氧的耐受性显著高于PES膜,但臭氧使2种膜的力学性能均有明显下降.
The effect of ozone on permeability, retention ability and mechanical properties of polyethersulfone(PES) and polyvinylidene fluoride(PVDF) membranes were investigated by static immersion experiments, and the changes in chemical composition and properties of PES and PVDF ultrafiltration membranes were analyzed. The pure water permeability of PES membrane increased to more than 3 times of the original membrane and the retention rate of humic acid(HA) by ozonated membrane decreased to about 0 after exposed to saturated ozonated water for 2 h at room temperature(20±1) ℃. Combing the analysis of composition and properties of the membrane surface, the hydrophilic additives polyvinylpyrrolidone(PVP) were oxidized, while PES molecules were seriously degraded, leading the destruction of the structure and function of PES separation layer. For the PVDF membrane, the pure water permeability of ozonated membrane was about 1.4 times of the original membrane and the HA rejection rate decreased from 61.1% to 41.2% after exposure to saturated ozonated water for 1 h. Moreover, the performances of the ozonated membranes did not further decrease with the extension of the exposure time. The analysis of the composition and properties of the membrane surface showed that the damage of the separation layer of PVDF membrane was mainly caused by the oxidation and loss of PVP, and PVDF matrix was not decomposed. The ozone resistance of PVDF membrane separation layer was significantly higher than that of PES membrane, but the mechanical properties of both membranes were significantly decreased by ozonation.
作者
李凯
徐维华
苏倩
文刚
黄廷林
LI Kai;XU Wei-hua;SU Qian;WEN Gang;HUANG Ting-lin(Collaborative Innovation Center of Water Pollution Control and Water Quality Security Assurance of Shaanxi Province,Shaanxi Key Laboratory of Environmental Engineering,Key Laboratory of Northwest Water Resource,Environment and Ecology,Ministry of Education,Xi'an University of Architecture and Technology,Xi’an 710055,China)
出处
《中国环境科学》
EI
CAS
CSCD
北大核心
2022年第3期1157-1163,共7页
China Environmental Science
基金
陕西省重点研发计划项目(2019ZDLSF06-01)
陕西省自然科学基金青年基金资助项目(2020JQ-672)
国家自然科学基金资助项目(51608427)。
