磷酸铝添加剂对聚偏氟乙烯膜抗污染性能的影响

考察添加剂磷酸铝(AlPO4)对聚偏氟乙烯(PVDF)膜性能的影响,分析模拟污染物的过滤行为机制。结果表明,AlPO4对PVDF膜的孔隙率和含水率无明显影响。适量添加Al PO4使PVDF膜的水通量、通量恢复率增加,提升PVDF膜的抗污染能力。AlPO4添加质量分数为2.5%时,PVDF滤膜的整体性能较优:水通量为246.4 L/(m^2·h),通量衰减系数0.22,牛血清白蛋白截留率95%,通量恢复率66%。采用AlPO4的质量分数2.5%制备的PVDF膜,模拟污染物(牛血清白蛋白、海藻酸钠、腐殖酸及其混合液)的过滤机制主要为滤饼过滤-标准堵塞型。

Effect of Aluminum Phosphate Additive on the Antifouling Properties of PVDF Membrane

The effect of aluminum phosphate(AlPO4) addition on the properties of PVDF membrane was investigated, and the filtration behavior of simulated pollutants was also analyzed. The results showed that AlPO4 had no obvious effect on the porosity and water content of PVDF membrane.Optimal addition of AlPO4 into the membrane phase increased the water flux and flux recovery rate of PVDF membrane, and the antifouling ability of PVDF membrane also enhanced. At 2.5% of mass fraction of AlPO4, the PVDF membrane exhibited better performance. The water flux, flux attenuation coefficient, BSA retention rate and flux recovery ratio were 246.4 L/(m^2·h), 0.22, 95% and 66%, respectively. Using prepared PVDF membrane with 2.5%of mass fraction of AlPO4, the filtration mechanism of simulated pollutants(bovine serum albumin, sodium alginate, humic acid and their mixture) was cake filtration-standard blocking model.