GO-TiO_2改性中空纤维膜的制备条件及抗污染性能研究

Study on preparation conditions and antifouling properties of GO-TiO_2 modified PVDF hollow fiber membrane

以氧化石墨烯(GO)与纳米二氧化钛(TiO_2)为改性剂,采用界面聚合法与抽滤吸附结合,对聚偏氟乙烯中空纤维超滤膜(简称原膜)进行表面改性,得到新型纳米改性膜(简称GO-TiO_2改性膜).研究改性膜的制备工艺条件及其对腐殖酸(HA)的吸附截留性能与抗污染特性.结果表明:(1)最佳制备工艺条件为:钛酸丁酯2 m L、GO 1 mg、间苯二胺1%(质量分数)、间苯二胺浸泡时间8 min、均苯三甲酰氯0.2%(质量分数)、均苯三甲酰氯浸泡时间10 min;(2)亲水性提高显著,亲水性表面为GO-聚酰胺-TiO_2复合结构,改性膜接触角由80.6°±1.8°下降到38.6°±1.2°;(3)抗污染性能提高明显.改性膜通量总衰减率由改性前的51.2%下降到35.6%,过滤周期约为原膜的2.5倍;反冲洗后膜通量恢复率由69%提高到96%.

The graphene oxide（ GO） and nano-titanium dioxide（ TiO2）-coated membrane（ for short GO-TiO2 modified membrane） were prepared with polyvinylidene fluoride hollow fiber ultrafiltration membrane（ for short PVDF membrane） as the raw material,GO and TiO2 as the modifiers,by using the interface polymerization method combined with the pumping adsorption as the modification technology. The preparation conditions of the GO-TiO2 modified membrane were investigated. The adsorption properties and interception behaviors of GO-TiO2 modified membrane to humic acid（ HA） and its antifouling characteristics were explored. The results show that：（1） The optimal preparation conditions were： butyl titanate 2 m L,GO 1mg,m-phenylenediamine 1%,the soak time in the m-phenylenediamine solution 8 mins,trimesoyl chloride 0. 2%,the soak time in the trimesoyl chloride solution 10 min;（2） The hydrophilicity of the PVDF membrane improved significantly. There is a special GO-polyamide-TiO2 composite structure,which is hydrophilic,on the surface of the GO-TiO2 modified membrane. The contact angle of the modified membrane decreased from 80.6° ±1.8° to 38.6° ±1.2°;（3） The antifouling properties were enhanced dramatically. The total flux decay rate of the GO-TiO2 modified membrane decreased from the original 51.2% to 35.6%,and the filtration cycle is proximately 2. 5 times that of the original PVDF membrane; The membrane flux recovery rate increased from 69% to 96% afterbackwashing.