Journal of Membrane Science, Vol.583, 180-189, 2019
Scale-up of NaA zeolite membranes using reusable stainless steel tubes for dehydration in an industrial plant
Large-scale NaA zeolite membranes in a length of 1000 mm were successfully synthesized for the first time on macroporous tubular stainless steel (MTSS) supports in this work. The influencing factors for membrane synthesis, such as pre-treatment, synthesis time, synthesis temperature, Na2O/SiO2 ratio, synthesis reproducibility, membrane stability and support reusability, were investigated systematically. The experimental results revealed that the high-flux NaA membranes prepared on the reusable MTSS supports exhibits a high total flux of 8.28 kg m(-2) h(-1) and a separation factor of 11,000 for the dehydration of a 90 wt% ethanol solution through pervaporation. The MTSS tubes can be used for at least 8 synthesis-rinse-synthesis circles, and the as-synthesized membranes still maintain high competitive pervaporation performance. Additionally, 93 pieces of membrane samples were assembled in an industrial plant that can produce approximate 99.8 wt% ethanol from 93 wt% ethanol mixtures with a product flow rate of about 60 kg h(-1). Importantly, the membrane showed a high stability for running over a whole month, demonstrating that the MTSS-supported membranes have reliable stability for industrial applications.