Comparative Study on Ammonia Adsorption Characteristics of Various Porous Materials and Ammonia Adsorption Effect According to MgCl2 Impregnation

Abstract

Ammonia plays a very important role as a fuel or as a potential source of hydrogen, and its separation and recovery are important in various processes. In this study, an adsorbent that can be applied to PSA processes over a wide temperature range was developed. To select the support, alumina silica, two types of zeolites, and carbon molecular sieves were considered and characterized through BET, TGA, NH₃-TPD, and high-pressure ammonia isotherm adsorption analyses. An adsorbent, Z-13X, whose adsorption and regeneration characteristics and structure of the support were kept constant was selected, and MgCl₂ was introduced into the support. The effect of introducing MgCl₂ was compared and analyzed according to the metal loading, and the impregnation of a certain amount of MgCl₂ maintained the structural characteristics of Z-13X and improved the adsorption performance. Additionally, it was confirmed that the adsorption performance increased near the initial low pressure and was excellent in terms of regeneration characteristics, heat of adsorption, and NH₃ selectivity.