The Efficiency of Carbon Dioxide and Hydrogen Sulphide Adsorption using Impregnated Granular Activated Carbon and Zeolite

Abstract

In this work, adsorbents granular activated carbon (GAC), granular activated carbon with acetylene (CVD/GAC) and zeolite A were applied for carbon dioxide (CO 2) and hydrogen sulphide (H 2 S) gas removal. The adsorbents were characterised by scanning electron microscope (SEM) and X-ray diffraction (XRD). Polyethyleneimine (PEI) in ethanol with initial concentration of 0.2 g l-1 and 1 mol dm-3 lithium nitrate (LiNO 3) were prepared to improve the adsorption capacity. In the impregnation process, various adsorbents, i.e., GAC, CVD/GAC and zeolite A were placed in a vial containing 0.2 g l-1 of PEI and 1 mol dm-3 of LiNO 3 solution, at different ratios of adsorbent and various solutions of 30%W/W. The adsorbents (GAC, PEI/CVD/GAC:PEI/GAC, LiNO 3 /CVD/GAC:LiNO 3 / GAC, zeolite 5A, PEI/zeolite 5A and LiNO 3 /zeolite 5A) were tested by using the synthetic biogas (45% CO 2 , 10% N 2 , 45% CH 4 and 105 mg dm-3 of H 2 S). The performance of CO 2 and H 2 S adsorption results have shown that PEI/CVD/GAC is the best adsorbent for low concentration of H 2 S and LiNO 3 /5A is the best adsorbent for CO 2 adsorption. The purity of the outlet methane was 96.6%,