DEVELOPMENT OF SELECTIVE SOLVENT FOR SEPARATION OF H2S GAS FROM CO2

• Main Author: Samara Andry Alamsyah, Sandra
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/84890
• Institution: Institut Teknologi Bandung

In natural gas processing, it is essential to separate major acidic impurities, CO2 and H2S. Common methods for acid gas removal include absorption using selective solvents like ionic liquids and amines. However, ionic liquids are costly and highly viscous, while amines can produce corrosive by-products and require high pressure. Therefore, research is being conducted to find alternative absorbents by mixing both types. This study investigated the optimal composition of ionic liquids and amines as selective solvents for separating H2S and CO2. The ionic liquids used are [EMIM][HSO4] and [EMIM][TFSI], while the amine used is TEA. The ionic liquid-amine ratios tested are 1:3, 1:1, and 3:1. Experiments were conducted by flowing the feed gases through a flow rotameter and reacting them with the absorbent in a vial. The outlet gas from the absorption chamber was directed to an acid room. The absorption process continued until the absorbent was saturated, with periodic vial mass measurements. Samples before and after absorption were characterized using FTIR to identify functional groups, and selectivity values were calculated. [EMIM][HSO4] demonstrated higher absorption capacity for CO2 and H2S due to its weaker bonds compared to [EMIM][TFSI]. For both IL variations, the highest CO2/H2S selectivity was achieved at a 1:1 ratio. The highest CO2/H2S selectivity was observed with [EMIM][HSO4] (1:1) at 0.84774, since TEA is more reactive towards CO2 and H2S, and [EMIM][HSO4] is selective for CO2 in the presence of H2S.