A novel process of cyclic adsorption and plasma-desorption for ppm-level CO removal from H2-rich stream

Abstract

A cyclic adsorption and plasma-desorption (CAPD) process is applied to remove ppm-level carbon monoxide (CO) from the H2-rich stream for the first time. In the CAPD process, CO is first selectively adsorbed on CuCl/γ-Al2O3 till adsorption saturation; Then, the adsorbed CO is in-situ desorbed by plasma generated in dielectric barrier discharge (DBD) and the adsorbent is regenerated simultaneously. The effects of discharge power (Pdis) and flow rate of discharge gas (FD) on performances of plasma-desorption are investigated. The time to reach desorption of 50% (t50) and 90% (t90) significantly decreases with Pdis but is weakly correlated to the FD. At the investigated conditions, t50 and t90 are lower than 2.6 min and 4.5 min, respectively, which indicates that plasma-desorption features high desorption rate. In addition, desorption efficiency of plasma-desorption is higher than 98%. Moreover, CAPD process stability is preliminarily confirmed by six consecutive adsorption-desorption cycles.