Acid treated mordenites as adsorbents of C2H4 and H2 gases

Abstract In this study, a mordenite-rich tuff (M) from the Şile region (NW Turkey) was treated with HNO 3 and H 2 SO 4 at various concentrations (1.0, 3.0 and 5.0 M) at 80 °C for 3 h. The adsorption properties of ethylene (C 2 H 4 ) and hydrogen (H 2 ) on natural and that of acid forms were examined experimentally at 273 and 77 K and up to 100 kPa using volumetric instrument, respectively. All the samples were characterized by X-ray diffraction (XRD), X-ray fluorescence (XRF), and nitrogen (N 2 ) adsorption methods. Some differences on XRD pattern were signed in between natural and acid modified samples according to the intensity, sharpness and crystallite degree of mordenite peaks. C 2 H 4 and H 2 adsorption capacities of the original and acid treated mordenites were in the range of 0.762–0.876 mmol g −1 and 1.373–1.672 mmol g −1 at 273 and 77 K, respectively. The increasing retention values of C 2 H 4 and H 2 after the acid treatments were analyzed in comparison with the structural changes.