Core Shell Nanostructure: Impregnated Activated Carbon as Adsorbent for Hydrogen Sulfide Adsorption.

This study focuses on the synthesis, characterization, and evaluation of the performance of core shell nanostructure adsorbent for hydrogen sulfide (H 2 S) capture. Commercial coconut shell activated carbon (CAC) and commercial mixed gas of 5000 ppm H 2 S balanced N 2 were used. With different preparation techniques, the CAC was modified by core shell impregnation with zinc oxide (ZnO), titanium oxide (TiO 2 ), potassium hydroxide (KOH), and zinc acetate (ZnAC 2 ). The core structure was prepared with CAC impregnated by single chemical and double chemical labelled with ZnAC 2 -CAC (single chemical), ZnAC 2 /KOH-CAC, ZnAC 2 /ZnO-CAC, and ZnAC 2 /TiO 2 -CAC. Then, the prepared core was layered either with KOH, TiO 2 , NH 3 , or TEOS for the shell. The synthesized adsorbents were characterized in physical and chemical characterization through scanning electron microscopy (SEM), thermal gravimetric analysis (TGA), and Brunauer-Emmett-Teller (BET) analyzers. Operation of the adsorber column takes place at ambient temperature, with absolute pressure at 1.5 bar. The H 2 S gas was fed into the column at 5.5 L/min and the loaded adsorbents were 150 g. The performance of synthesized adsorbent was analyzed through the adsorbent's capability in capturing H 2 S gas. Based on the results, ZnAc 2 /ZnO/CAC_WOS shows a better adsorption capacity with 1.17 mg H 2 S/g and a 53% increment compared to raw CAC. However, the degradation of the adsorbents was higher compared to ZnAc 2 /ZnO/CAC_OS and to ZnAc 2 /ZnO/CAC_WS ZnAc 2 /ZnO/CAC_OS. The presence of silica as a shell has potentially increased the adsorbent's stability in several cycles of adsorption-desorption.