Ethylene/ethane separation by facilitated transport membrane accompanied by permeation of aqueous silver nitrate solution

摘要

A novel facilitated transport membrane, a bulk flow liquid membrane (BFLM), was applied to ethylene/ethane separation using silver nitrate as a carrier. In this membrane system, a carrier solution is supplied to the feed gas side (high pressure side) of a UF membrane and is allowed to permeate to the permeate side (low pressure side). The transferred carrier solution is recycled to the feed side. The effect of such convective flow of the carrier solution through the membrane on ethylene permeance was investigated using a dead-end type filtration cell equipped with an ultrafiltration membrane. The C_2H_4 permeance, R_(C_2H_4), increased iwth increasing the volumetric permeation flux of the carrier solution #mu#, and when #mu# was 4 X 10~(-5) m s~(-1) and the C_2H_4 partial pressure was 9 kPa, R_(C_2H_4) was 4 X 10~(-5) mol m~(-2) s~(-1) kPa~(-1) and the selectivity of C_2H_4 over C_2H_6 was 1100. This value was approx = 30 times that at u = 0. This type of membrane was very stable during intermittently performed experiments for more than 2 months.