摘要
本文报道了用sol—gel法在多孔α-Al_2O_3陶瓷底膜表面制备复合γ—Al_2O_3超滤膜的研究工作。实验采用了孔径与溶胶离子大小相适应的多孔底膜,以吸镀法镀膜并进行增湿慢速控制干燥,以避免膜表面产生针孔和裂缝。文章指出干燥过程是保证膜完整的关键步骤。H_2、N_2渗透力与理想分离系数的测试结果说明分离主要以诺森扩散机制进行。分离系数达到了Alcoa公司产品水平,但支撑底膜传质阻力过大,结构应加以改进。
A composite membrane consisting of γ-Al_2O_3 Ultrafiltration layer and porous α-Al_2O_3 Ceramic support is prepared by sol—get technigue. Ceramic Support with its mean pore diameter suitable for particle size of asls is required. Process of vacuum coating and slow drying in humid air is applied to retain the membranes free of pinhols and cracks. The remark influence of drying condition on membrane integrity is pointed out. H_2, N_2 Permeability measurements show that the separation is controlled by Knudsen diffusion mechanism. Ideal separation factors are equivaient to Alcoa product, but the support must be improved to decrease permeation resistance.
出处
《膜科学与技术》
CAS
CSCD
1993年第4期29-33,共5页
Membrane Science and Technology
关键词
溶胶
凝胶
干燥
超滤膜
氧化铝
Composite membrane, γ-Al_2O_3, Preparation, sol—gel, drying
