支撑体生坯浸涂溶胶(一步法)制备不对称结构陶瓷超滤膜的研究

PREPARATION OF ASYMMETRIC CERAMIC ULTRAFILTRITION BY DIP-COATING BOEHMITE SOL ON UNFIRED SUPPORT (ONE STEP PROCESS)

无机陶瓷膜的低成本化日益受到重视。在此以降低陶瓷膜制备成本为出发点,采用在支撑体生坯上浸涂勃姆石溶胶,经干燥烧结后制备具有不对称结构的无机陶瓷超滤膜。考察了更具成本优势的常温水解氯化铝制勃姆石溶胶和传统异丙醇铝制勃姆石溶胶两种溶胶在涂膜时缺陷控制的方法。溶胶中添加PVA可以有效降低溶胶涂层缺陷。在支撑体生坯上浸涂勃姆石溶胶,支撑体与涂层一次烧结制备的不对称结构的陶瓷膜孔隙率与未涂膜支撑体相同,对PVA1750的截留率为90.7%。相对于传统烧成支撑体涂膜的多次烧结工艺,表现出了更低成本优势。

Nowadays ceramic membranes have been used in many separation industries. To decrease the manufacturing cost of ceramic membrane, cost control has been paid more attention. A novel process of asymmetric ceramic membrane prepared by dip-coating beohmite sol on unfired ceramic support was adapted. The boehmite sol prepared from aluminum chloride hydrolyzed at room temperature, which has advantage in cost, and the boehmite sol prepared from aluminum isopropoxide were studied in surface coating to decrease the defects of dip-coating film. The results showed that the asymmetric ceramic ultrafiltration can be prepared by using one step technique. The prepared asymmetric ceramic membrane had same porosity to sintered support, and its retention to PVA1750 was 90.7%.