Desorption of CO2 Gas in KOH Solution by Using Gas Absorption Column

Technological developments in industry will lead to increased energy consumption. Human dependence on fossil resources will trigger serious problems with air pollution due to high CO2 gas emissions while nature's ability to accept pollutant loads is very limited. To solve this problem, CO2 gas capture is carried out from the source. CO2 gas capture is done using Carbon Capture and Storage (CCS) technology. This technology converts CO2 gas emissions into hydrocarbons through a hydrogenation process. One form of this technology in the form of Gas Absorption Column is a type of reactor in a closed column that uses absorbents in the form of KOH as a promoter. The purpose of this research is to determine the optimum solution and gas flow rates with variations of 2, 4, and 6 L/min on the KOH solution, and 10, 20 and 30 L/min on the gas flow rate, while the fixed variable is air injection of 10 L/min. The methods used are sampling and alkalimetric methods. This method is used when the absorption process runs for 20 minutes with a sampling time of every 5 minutes which each sample will be analyzed in the form of pH, temperature, and EC and dissolved CO2. The analysis showed an effective flow rate of 2 L/min on solution and 30 L/min on CO2 gas. The concentration captured was 114 mg/L by removing 52% of the absorbed concentration. In addition, from the results of pH analysis, there was a decrease due to mass transfer that occurred and inversely proportional to temperature and EC which increased. It can be concluded that the flow rate of the solution will affect the contact time of the adopted CO2 gas. Meanwhile, the higher the CO2 gas flow rate, the greater the CO2 absorbed in the absorpben.