Removal of H₂S from Rich Solution in Absorption Process by Utilizing Thiobacillus.sp

Chemical Engineering Department, Faculty of Engineering, Universitas Sumatera Utara, Jalan Almamater Kampus USU, Padang Bulan, Medan 20115, Indonesia

^* Corresponding author: b_trisakti@usu.ac.id

Abstract

The content of hydrogen sulphide in the rich solution from absorption process is a contaminant type toxic and hazardous waste which has negative impact on the environment. This study aims to reduce H₂S in rich solution by utilizing Thiobacillus sp. The utilization of Thiobacillus sp was carried out at ambient temperature, pH ranging from 8.5 to 9.3, facultative aeration with variations in initial H₂S concentrations (1,000, 2,000 and 3,000 ppm) and an initial microbial to H2S solution (1:5, 1:3 and 1:1). H₂S concentration analysis was performed to determine the efficiency of H2S reduction by using iodometric titration method. Analysis of total solids (TS), volatile solids (VS), total suspended solids (TSS), volatile suspended solids (VSS), chemical oxygen demand (COD), pH, and M-Alkalinity were performed to determine water quality resulted from the reduction by Thiobacillus sp. The highest H₂S reduction efficiency by Thiobacillus sp at 70% was obtained by initial H₂S concentrations of 3,000 ppm and the initial microbial ratio of H₂ at 1: 3 solution with TS, VS, TSS, VSS, COD, pH and Alkalinity values were 5,040 mg/L, 2.420 mg/L, 1.030 mg/L, 690 mg/L, 126 mg/L, 8.1 - 9.6, and 750 mg/L respectively.