脱乙酰基改性乙酸纤维薄膜对乳化油分离及积垢机理的探究

Study on the separation of emulsified oil and fouling mechanism by deacetylated cellulose scetate membrane

利用静电纺丝制造乙酸纤维素膜(CA纤维膜),并利用添加TiO_(2)及脱乙酰基(d-CA)对CA纤维膜进行改性,后续对膜过滤特性、渗透通量、油水乳化液去除效率、反洗特性及积垢机制进行讨究。结果显示,CA纤维膜通过TiO_(2)及d-CA改性后可以提高膜的热稳定性及亲水性能,并得到稳定的纯水通量和过滤通量;最佳的比例为TiO_(2)@d-18.5%CA纤维膜,在40kPa跨膜压差、60min的操作条件下,其纯水通量、过滤通量、1g/L油水乳化液去除效率以及反洗后通量分别为824.8L/(m^(2)·h)、(311.3±12.5)L/(m^(2)·h)、93.6%±1.1%、451.5L/(m^(2)·h);另外,添加TiO_(2)可能导致油水乳化液在膜表面不可逆阻力比例的增加,脱乙酰基改性CA纤维膜则可以降低膜自身阻力及增加可逆阻力的比例,提高CA纤维膜在油水分离方面的潜力。

In this research,the cellulose acetate membrane(CA fiber membrane)was produced by electrostatic spinning,and the prepared CA membrane was modified by added TiO_(2) powder and deacetylated cellulose acetate(d-CA).After,the membrane filtration characteristics,permeation flux,removal efficiency of oil/water emulsion and membrane resistances were discussed.The results showed that the thermal stability and superhydrophilicity of the modification CA fiber membrane could be improved by TiO_(2) and D-CA,and the stable water and filtration flux were obtained.In operation conditions at 40kPa and 60 minutes,the TiO_(2)@d-18.5%CA membranes were good membrane with water flux,filtration flux,removal efficiency of oil/water emulsion and backwash flux of 824.8L/(m^(2)·h),(311.3±12.5)L/(m^(2)·h),93.6%±1.1%and 451.5L/(m^(2)·h),respectively.The addition of TiO_(2) might lead to an increase in the irreversible resistance ratio of oil on the membrane surface.However,the d-CA modified could reduce the fiber membrane resistance and increase the proportion of reversible resistance,and improve the potential of CA fiber membrane in oil-water separation.