介孔TiO2膜的制备及其吸附性能研究

摘要

A stable TiO2 sol was synthesized from titanium isopropoxide by colloidal sol-gel route.Mesoporous TiO2 membranes were prepared with tubular Al2 O3 microfiltration membrane of 100 nm pore size as support by dip-coating method.The effect of preparation process on integrity and pore structure of mesoporous TiO2 mem-brane was studied in detail.In addition,the absorption of acid orange 7 and methylene blue onto unsupported mesoporous TiO2 membrane was researched.Defect-free mesoporous TiO2 membranes were obtained from TiO2 sol added appropriate amount of PVA and HPC as binder by time-controlled dip-coating followed by calci-nation at 450 ℃ for 1h.The thickness of TiO2 membrane was about 0.5μm and the pore size distributes in the range of 3-10 nm.The absorption of acid orange 7 and methylene blue onto mesoporous TiO2 membrane varies with pH value.It implies that adusting pH value may decrease membrane fouling caused by the adsorption.%以钛酸四异丙脂为原料,采用粒子型溶胶路线制备出稳定的 TiO2溶胶,通过浸渍涂膜法,在孔径为100 nm的管式Al2 O3微滤膜支撑体上制备出介孔TiO2膜。研究了介孔TiO2膜的制备过程对其完整性及孔结构的影响,同时考察了非负载介孔 TiO2膜对染料酸性橙7和亚甲基蓝的吸附性能。在溶胶中加入适量的 PVA 和 HPC,控制浸涂时间,在450℃焙烧1 h可获得完整的介孔TiO2膜,膜厚约0.5μm,孔径分布于3~10 nm。介孔TiO2膜对酸性橙7及亚甲基蓝吸附量随 pH 值变化,调节 pH 值可减少吸附造成的膜污染。