Preparation and characterization of soybean straw activated carbon for natural gas storage

Abstract

Adsorbed natural gas (ANG) can be developed through its porous adsorbent, especially activated carbon (AC) which has larger specific surface area. AC made of soybean straw is developed because of its abundance as agricultural waste in Indonesia and high lignocellulosic content. AC is produced in 500°C furnace for 1 hour with nitrogen gas flow of 200 mL/minute. For AC production, variations of chemical activating agents utilizing ZnCl2 and KOH and the concentration NiO as modification substance are made in this paper. Characterizations are made through iodine number, SEM, EDX, and nitrogen adsorption-desorption for obtaining data of adsorption capacity, surface topography, main composition, and particles specification. ZnCl2 activated carbon shows better result with iodine number of 577.73 mg/g and SBET of 741.26 m2/g, and the second-best is found in 2%-NiO-modified ZnCl2 activated carbon with iodine number of 534.79 mg/g and SBET of 632.24 m2/g. It is concluded that development of soybean straw as activated carbon precursor is still needed to obtain larger SBETand better adsorption capacity.