Ammonia removal by natural modified clinoptilolite

Abstract

In this study, cation exchange and acid activation processes were applied to determine the effects of different cationic compositions of clinoptilolite on ammonia (NH3) adsorption properties. Thermogravimetric (TG), differential thermal analysis (DTA), X-ray diffraction (XRD), X-ray fluorescence (XRF) and nitrogen adsorption techniques were used for the characterization of the clinoptilolite samples. As a result of ion exchange and acid activation, the amount, type, and location of exchangeable cations in the structure significantly affected the thermal properties as well as NH3 removal efficiency. Ammonia adsorption isotherms were obtained at 298 K up to 100 kPa volumetrically. In addition, NH3 adsorption capacities of the clinoptilolite samples within this study (3.823 to 5.372 mmol g-1) were compared with those of the other materials (1.77 to 12.2 mmol g-1) in terms of their textural and structural differences.