Syngas Production from Lignite Coal Using K2CO3 Catalytic Steam Gasification with Controlled Heating Rate in Pyrolysis Step

Abstract

Gasification uses steam increases H2 content in the syngas. Kinetics of gasification process can be improved by using K2CO3 catalyst. Controlled heating rate in pyrolysis step determines the pore size of charcoal that affects yield gas and H2 and CO content in the syngas. In previous research, pyrolisis step was performed without considering heating rate in pyrolysis step. This experiment was performed by catalytic steam gasification using lignite char from pyrolysis with controlled heating rate intended to produce maximum yield of syngas with mole ratio of H2/CO ≈ 2. Slow heating rate (3°C/min) until 850°C in the pyrolysis step has resulted in largest surface area of char. This study was performed by feeding Indonesian lignite char particles and K2CO3 catalyst into a fixed bed reactor with variation of steam/char mole ratio (2.2; 2.9; 4.0) and gasification temperature (750°C, 825°C, and 900°C). Highest ratio of H2/CO (1.682) was obtained at 750°C and steam/char ratio 2.2. Largest gas yield obtained from this study was 0.504mol/g of char at 900°C and steam/char ratio 2.9. Optimum condition for syngas production was at 750°C and steam/char mole ratio 2.2 with gas yield 0.353mol/g of char and H2/CO ratio 1.682.