Adsorption of Activated Carbon from Coal on Coal Briquette Combustion Flue Gas

Abstract

Coal briquette is expected to be able to become low-cost alternative energy source. However, coal briquette combustion produces gas emission such as SO2, NOx, CO, and CO2 that cause air pollution. The objective of this research is to minimize flue gas emission by using activated carbon made from low level coal such as lignite, obtained from South Sumatera. Activated carbon formation is conducted by using chemical activation method, with ZnCl2 composition variations of 25%, 30%, 35%, 40%, and 45% and coal grain size of 40 mesh, 60 mesh, 80 mesh, and 100 mesh. Carbonization process was conducted at 500°C for 2 hours. Carbonization was conducted by using an air tight steel box infused by nitrogen along the process. The result of this research shows that the composition of ZnCl2 40% and coal 60% with 80 mesh of coal grain size, is the optimum condition to produce activated carbon with highest iodine value of 1323 mg/g. in the application of coal briquette flue gas adsorption experiment, the activated carbon is highly effective in absorbing NO2 with adsorption volume of 87.6 - 90.8%. SO2, CO2, and poly aromatic hydrocarbon (PAH) gas adsorption levels are varied from 27% to 47.8%, but not really effective in absorbing CO gas with adsorption capacity of 11.5%. The activated carbon utilized in this research has the potential to be developed as effective adsorbent for coal combustion exhaust gas emission.