摘要
在溶胶凝胶法颗粒溶胶路线制备α相氧化铝超滤膜的基础上,通过添加适量的氧化铝晶种促进勃姆石在较低的相转变温度下实现从无定型态向完全α相的晶型转变过程,以减弱氧化铝晶粒在完成α相形核后因高温继续生长,进而获得由较小氧化铝颗粒堆积的膜孔,制备出具有良好截留性能的小孔径氧化铝超滤膜.结果表明:按照此种方法添加6dwb%(dwb%是指相对于所制得氧化铝质量分数)氧化铝晶种,勃姆石即可在1 000℃、保温1h的条件下发生完全的α相转变,所制备的α相氧化铝超滤膜的截留性能相比于由纯勃姆石制备的氧化铝超滤膜有了较大的提升,证明孔径缩小,其葡聚糖的切割相对分子质量为13 000,对应膜孔径为5.2nm,纯水渗透率为1 400L/(m2·h·MPa).
Small diameter alumina ultrafiltration membranes were prepared via a colloidal sol-gel route by addingα-Al2O3 seeds. The effects of adding α-Al2O3 seeds on the phase transition of alumina derived from boehmite and the microstrueture of alumina membranes were investigated at various temperatures. Results showed that the addition of α-Al2O3 seeds plays an impressive role on the promotion of alumina phase transition. The alpha transformation of alumina can be accomplished completely by adding 6dwb%α-Al2O3seeds at 1 000 ℃ for 1 h holding time. Comparing to the membrane without adding α-Al2O3 seeds, alpha alumina ultrafiltration membrane prepared by adding α-Al2O3 seeds showed relatively small pore size and high retention performance. The molecular weight cut off obtained from the retention of dextran was calculated to be 13 000, corresponding to an average pore size of 5.2 nm. Meanwhile, such membranes exhibited high pure water permeability of 1 400 L/（m2 · h · MPa）. Theα-Al2O3seeds assisted colloidal sol-gel method showed a good potential to prepare tight alpha alumina ultrafiltration membrane from boehmite sol.
出处
《膜科学与技术》
CAS
CSCD
北大核心
2016年第1期12-16,22,共6页
Membrane Science and Technology
基金
国家"863"计划课题(2012AA03A606)
江苏高校优势学科建设工程资助项目(PAPD)
关键词
溶胶凝胶法
α相氧化铝
晶种
超滤膜
sol-gel
alpha alumina
α-Al2O3seeds
ultrafiltration membrane
