PEMODELAN MATEMATIS DAN PENYELESAIAN NUMERIS PADA ABSORBSI H2S MENGGUNAKAN LARUTAN ABSORBEN FE-EDTA DALAM PACKED COLUMN

Abstract

Biogas and natural gas are very potential to be used as fuel because of its high content of methane. The disadvantage of biogas and natural gas as fuel was its high content of hydrogen sulfide (H2S) which is potential to pollute the environment. Because of this, biogas should be purified first before being used as fuel. Generally, the content of H2S can be reduced physically, chemically or biologically methods, but these methods have many disadvantages. Gas purification from the content of H2S by using Fe-EDTA (Iron Chelated Solution) gives several advantages. The advantages are the absorbent solution can be regenerated that means a cheap operation cost, the separated sulfur is a solid (that is an economic commodity) or residue that is easy to handle and is safe to be disposal to environment. In the previous research, H2S was absorbed into Fe-EDTA solution in packed bed column. Fe-EDTA solution concentration that used was 0.1 M and 0.2 M. In this research mathematical model representing the absorption process was arranged to search the mass transfer coefficient and reaction rate constant value. By arrangement of each component molar balance was obtained five differential equations. By obtained data in the previous research, these equations had been solved using numeric solution (MATLAB program). The result showed that for absorbent flow rate 5.4 to 7.7 L/minute in 0.1 M Fe-EDTA concentration, the mass transfer coefficient of liquid fase value had range 0.00182 to 0.00219 1/menit and the reaction rate constant value had range 1686.6 to 1711.4 liter2 /mol2 .menit, while in 0.2 M concentration of absorbent the mass transfer coefficient of liquid fase value had range 0.01223 to 0.01289 1/menit and the reaction rate constant value had range 1934.8 to 2130.7 liter2 /mol2 .menit. The higher absorbent concentration, the higher mass transfer coefficient of liquid fase value and reaction rate constant value.