ePTFE/PP和PVDF亲水膜的化学稳定性研究

Chemical Stability of ePTFE /PP and PVDF Hydrophilic Membranes

将ePTFE/PP和PVDF亲水膜分别浸泡在pH值=1、2、3的HCl溶液,pH值=11、12、13的NaOH溶液,2.0%的H2O2溶液,和0.5%、2.0%的NaClO溶液中,于40℃的恒温箱中分别静置20、40、60 d后,通过测定清水通量和电镜扫描(SEM)观察,对两种亲水膜的化学稳定性进行了比较。与PVDF膜相比,ePTFE/PP亲水膜的化学药剂耐受性能更好(耐酸性>耐氧化性>耐碱性)、初始通量更高[为312.47 L/(h·m2),远大于PVDF膜的42.15 L/(h·m2)],而且保持了较好的膜片结构完整性。这可为ePTFE/PP亲水膜在油田采油废水回注与配聚中的应用,以及膜污染后的化学清洗提供化学稳定性方面的理论依据。

ePTFE/PP and PVDF membranes immersed in HC1 with pH of 1,2 and 3, NaOH with pH of 11, 12 and 13, 2.0% H202, and 0.5% and 2.0% NaC10 were placed in 40 ~C thermostat for 20, 40 and 60 d. The chemical stability of ePTFE/PP and PVDF hydrophilic membranes was investigated by water flux measurement and SEM. ePTFE/PP hydrophilic membrane has an advantage over PVDF hy- drophilic membrane in chemical resistance （acid resistance 〉 oxidation resistance 〉 alkali resistance）, initial flux [ 312.47 L/（ h· m2） for ePTFE/PP and 42.15 L/（ h · m2） for PVDF ] and membrane struc- tural integrity. This provides a theoretical basis for the application of ePTFE/PP hydrophilic membrane in oil-field wastewater reinjection, polymer solution preparation, and especially chemical cleaning after membrane fouling.