γ-Al_2O_3微孔膜制备及其处理电镀废水的研究

Preparation of γ-Al_2O_3 Membrane and Its Application in Electroplating Wastewater Treatment

膜分离技术在电镀废水处理领域有着良好的应用前景。以异丙醇铝为主要原料,经酸解、除醇、干燥和烧结过程制备陶瓷膜。采用8 nm粒径溶胶多次真空覆涂-焙烧法,在1℃/m in的焙烧条件下制备了非对称氧化铝微孔膜。测试了陶瓷膜的纯水通量、膜截留性能、膜流动电位,结果表明:经过4次的浸涂成膜,纯水通量为3.55×103L/(MPa.h.m2),达到超滤膜的要求;通过截留率计算膜片平均孔径为28 nm;流动电位为-20 mV。将制得的陶瓷膜用于电镀废水处理,COD去除率为85%,在透过液中Cu、Cr、N i浓度分别为0.0663、0.0051和0.0763 mg/L,回用废水可满足电镀前处理的使用要求。

Membrane separation technology has wide application in electroplating wastewater treatment. A vacuum-assisted dipcoating （VADC） and slip-casting method has been developed for the deposition of sol-gel to prepare γ-Al2O3 membrane. Aluminum isopropoxide was used to prepare non-symmetrlcal γ-Al2O3 membrane through aeidolysis, dealcoholization, drying and sintering, The mean pore size of prepared membrane was 28 nm, water flux was 3.55 ×10^3 L/（ MPa·h· m^2 ） at 0.2 MPa of transmembrane pressure, and the streaming potential was -20 mV. The ceramics membrane was used to treat electroplating wastewater. The rejected rate of COD was 85% and concentrations of Cu, Cr and Ni in the filtrate were 0. 0663,0. 0051 and 0. 0763 mg/L, respectively. The wastewater recycling can meet the recycling demand of electroplating pretreatment.