Vacuum Swing Adsorption for Propylene/Propane Separation with 4A Zeolite

A vacuum swing adsorption process using 4A zeolite pellets with five steps was designed to split an equimolar mixture of propylene/propane. The equimolar feed of C 3 is diluted to 50% with nitrogen at 5 bar and 423 K, and the product is obtained when the total pressure is lowered to 0.1 bar. After 15 cycles, cyclic steady-state conditions are reached, a propylene-enriched stream of 97 mol% relative to the propylene/propane mixture, with 4.4% of nitrogen, a recovery of 26% (molar basis), and a productivity of 1.03 mol/(kg h) are obtained. The experimental work is compared with numerical simulations, and the effects of different operating parameters on the VSA process are analyzed.