CPAM-assisted synthesis of NaA zeolite membrane on macroporous mullite hollow fiber for ethanol dehydration by pervaporation  

作　　者：Liqin Tang Xiang Jin Bing Gao Xuechao Gao Xuehong Gu 

机构地区：[1]State Key Laboratory of Materials-Oriented Chemical Engineering,College of Chemical Engineering,Nanjing Tech University,Nanjing 211816,China

出　　处：《Chinese Journal of Chemical Engineering》2025年第1期66-80,共15页中国化学工程学报(英文版)

基　　金：supported by the National Natural Science Foundation of China(22178166);Jiangsu Provincial Special Funds of Scientific and Technological Innovation for Carbon Peak and Carbon Neutrality(BE2022033-1,BE2022033-4);Chongqing Municipal Bureau of Science and Technology(cstc2021jcyj-msxmX0748).

摘　　要：Due to the low transport resistance,mullite hollow fiber(HF)could be regarded as a promising support for preparation of NaA zeolite membranes.However,insufficient coverage and undesired seed penetration often occur in the seeding step of the mullite support due to the rough surfaces with ultra-large macropores(2-4 μm).This leads to poor intergrowth of the membrane layer.To solve this issue,cationic polyacrylamide(CPAM)was employed to modify the chemical and electrostatic properties of the mullite HF surface,where the electrostatic attraction between the surface and seed crystals could significantly promote the coating effect.In the seeding,the original seeds(3.2 μm)were mixed with the ball-milled seeds(0.3 μm)to improve the seed coverage,i.e.,the original seed was used to block the macropores on the support surface to prevent the penetration of small seeds,while the decked ball-milled seed was used to provide sufficient active sites to induce the intergrowth of the zeolite crystals.The effects of the concentration of CPAM,mixed mass ratio of seeds,and seed concentration on the preparation of NaA zeolite membranes were systematically examined,where the separation performances were characterized by pervaporation(PV)dehydration of 90%(mass)ethanol/water mixtures at 75℃.The results indicated that under a CPAM concentration of 0.7%(mass),an equivalent mass ratio of mixed seeds in a seed concentration of 1.0%(mass),the prepared mullite HF supported NaA zeolite membrane yielded the best PV performance,where the permeation flux and separation factor corresponded to 5.45 kg·m^(-2)·h^(-1)and 10000,respectively,being sufficient for industrial applications.

关 键 词：CPAM-Modification NaA zeolite membranes Mullite hollow fiber SEEDING PERVAPORATION 

分 类 号：O64[理学—物理化学]