非对称性微孔复合陶瓷膜制备技术研究

Study on Preparation Technique of Unsymmetrical Microporous Composite Ceramics Membranes

采用压制-烧结法制备多孔氧化铝陶瓷片,并采用溶胶-凝胶法在多孔氧化铝陶瓷载体上依次沉积孔径逐渐减小的氧化铝陶瓷膜、氧化锆陶瓷膜和氧化钛陶瓷膜,从而得到具有非对称性结构的多孔复合陶瓷膜.采用压制-烧结法,将粉末造粒、压制、干燥,然后烧结,可分别得到平均孔径大约为2μm,6μm,10μm的多孔陶瓷片,该多孔陶瓷片的开口孔隙率大于40%,断裂强度大于50N.以此陶瓷片作载体,经溶胶-凝胶法多次涂敷不同的溶胶,可分别得到孔径大约为200nm,400nm和600nm,厚度大约为40μm的多孔复合陶瓷膜.此多孔复合陶瓷膜可作为气体及液体的过滤材料,也可以作为钯合金膜的支撑体.

The press - sintering process was developed to prepare Al2O3 microporous ceramics, and these ceramics were coated with Al2O3, ZrO2 and TiO2 membrane by sol - gel method to obtain the unsymmetrical composite ceramics membranes in this paper. In the press - sintering process, the powder was agglomerated,and the w(PVA) was controlled at 15%, 25% and 30%, the agglomerated powder was 10μm in size, thenpressed and sintered at 1250℃, and microporous ceramics with pore diameter of 2μm, 6μm and 10μm, open pore ratio higher than 40% , crushing strength of 50N could be achieved. Using the microporous ceramics withpore diameter of 2μm, 6μm and 10μm as substrate, sol - gel concentration of 0.5g/mL(salt), the substrateswere dried slowly at 25℃ and 80℃ successively, then sintered at 1000℃, the unsymmetrical composite ceramics membranes with pore diameter of 200nm, 400nm and 600nm, thickness of about 40 m could be developed by the sol - gel method. The membranes can be used as filter for gas or liquid, especially be used as substrate for Pd - Ag alloy membrane.