The Adsorption and Desorption Breakthrough Behavior of Hydrogen Chloride Gas Mixture on Zeolite 13X Pellet in a Fixed Bed Reactor

Abstract

The adsorption and desorption breakthrough test of hydrogen chloride (HCl) was performed by loading zeolite 13X pellet (molecular sieve 13X, Aldrich Co., U.S.A.), a commercial adsorbent, onto a fixed bed reactor (height 15 cm, inside diameter 0.5 cm). The breakthrough test was carried out by changing various experimental conditions such as inlet flow rate (0.5, 1, 1.5, 2 L/min), HCl concentration (200, 350, 500, 650 ppm), reaction temperature (30, 50, 70, 90°C), and reaction pressure (1, 5, 10, 15, 20 bar) with considering the retention time and space velocity. After evaluating the adsorption and the desorption characteristics of HCl on the MS-13X, the consecutive cyclic test (5 times of adsorption step, 4 times of desorption step) was carried out with optimum condition. At the adsorption step, pressure was 20 bar, temperature was 30°C, HCl concentration was 200 ppm, total inlet flow rate was 0.5 L/min (HCl+N2). At the desorption step, pressure was 1 bar (atmospheric pressure), temperature was 280°C, total inlet flow rate was 0.5 L/min (N2 only), desorption time (regeneration time) was 7 h. The optical, physical, and chemical characteristics of MS-13X were analyzed using BET, XRD, SEM, EDX, and TGA before and after breakthrough tests.