Shraavya Rao, Xuepeng Deng, Changlong Zou, Babul Prasad, Yang Han, Li-Chiang Lin, W.S. Winston Ho
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引用次数: 0
Abstract
Facilitated transport membranes (FTMs) show great promise for H2S/CO2 separation, an industrially important yet challenging process. Herein, we report FTMs with excellent H2S/CO2 separation performance and investigate how contradictory thermodynamic and kinetic reaction preferences affects FTM selectivity. For membranes based on an extremely sterically hindered di-tert-butylamine carrier, CO2 transport occurs exclusively via a slow bicarbonate pathway. Reducing the membrane thickness shifts the reaction preference from the thermodynamically favored bicarbonate pathway to the kinetically favored amine-H2S reaction, leading to a 10-fold improvement in H2S/CO2 selectivity. This unusual trend of increasing selectivity with decreasing thickness, the opposite of typical FTMs, enables simultaneous improvements in membrane permeance and selectivity. This translates to an exceptional H2S/CO2 permselectivity of 20, and an overall separation performance surpassing the H2S/CO2 upper bounds.
期刊介绍:
The Journal of Materials Chemistry A, B & C covers a wide range of high-quality studies in the field of materials chemistry, with each section focusing on specific applications of the materials studied. Journal of Materials Chemistry A emphasizes applications in energy and sustainability, including topics such as artificial photosynthesis, batteries, and fuel cells. Journal of Materials Chemistry B focuses on applications in biology and medicine, while Journal of Materials Chemistry C covers applications in optical, magnetic, and electronic devices. Example topic areas within the scope of Journal of Materials Chemistry A include catalysis, green/sustainable materials, sensors, and water treatment, among others.