摘要
研究了一次刮膜形成偶联层的涂覆液组成与刮膜厚度以及二次刮膜铸膜液的配方与成膜工艺,利用扫描电子显微镜(SEM)、X射线光电子能谱仪(XPS)等对制备的膜组成及结构进行了表征。首先通过聚合物共混相容性实验筛选出聚甲基丙烯酸甲酯(PMMA)作为支撑层聚酯无纺布与聚偏氟乙烯(PVDF)铸膜液之间的偶联层聚合物,确定一次刮膜涂覆液中PMMA的质量分数为12%,刮膜厚度为20μm;然后优化确定了二次刮膜铸膜液配方NMP/PVDF/PMMA/PVP质量比为74/16/4/6。经二次刮膜法制备的聚偏氟乙烯平板复合超滤膜机械强度高,抗反洗能力强,主体材料为PVDF,在0.1 MPa条件下纯水通量稳定在628.1 L/(h·m^2),接触角为53.7°,用于实际石化废水处理运行1个月膜平均产水通量约为68.3 L/(h·m^2),产水浊度基本稳定在0.2~0.6 NTU之间,膜表面污染物较少,抗污染能力强。
Composition of coating solution and thickness of casting membrane in forming a coupling layer by the first time casting membrane are studied,and the casting solution formula and making-membrane technique of the second time casting membrane is also studied.The composition and structure of membrane are characterized by scanning electron microscopy（ SEM）,X ray photoelectron spectroscopy（ XPS）,etc. Firstly,through the compatibility experiments of polymer blends,polymethyl methacrylate（ PMMA） is screened out as the coupling layer polymer between the support layer polyester non-woven fabric and polyvinylidene fluoride（ PVDF） casting solution. It is confirmed that the mass concentration of PMMA in the coating solution of first time casting membrane is 12% and the thickness of casting membrane is 20 μm. Then the solution formula of the second time casting membrane is optimized as NMP/PVDF/PMMA/PVP = 74/16/4/6（ mass percent）. The PVDF flat composite ultrafiltration membrane prepared by the twice casting method has a high mechanical strength and strong anti-backwashing ability. With PVDF as the bulk material,it can remain pure water flux steady at 628. 1 L·（ h·m^2）-1under 0. 1 MPa when the contact angle is 53. 7°. Having been used in the actual operation of petrochemical wastewater treatment for one month,the average membrane water flux is about 68. 3 L·（ h·m^2）-1,and the turbidity of production water is basically stable between 0. 2 NTU and 0. 6 NTU.The surface of membrane is less pollutant,showing a strong anti-pollution ability.
出处
《现代化工》
CAS
CSCD
北大核心
2017年第7期133-137,共5页
Modern Chemical Industry
基金
中国石油化工股份有限公司开发项目(312071)
山东省自然科学基金资助项目(ZR2010BM037)
关键词
聚偏氟乙烯
平板复合膜
二次刮膜
亲水性
增强型
polyvinylidene fluoride
flat composite membrane
twice casting membrane
hydrophilicity
reinforced
