Precursor suitability and pilot scale production of super activated carbon for greenhouse gas adsorption and fuel gas storage

Abstract

Raw and calcined petroleum cokes of Indian origin were characterized and screened as a carbon precursor for the preparation of activated carbon on medium and pilot scale by chemical activation method. Raw petroleum coke (RPC) was found more suitable precursor for preparation of activated carbon, whereas the enhanced graphitic arrangement limits the applicability of calcined petroleum coke. The suitability of petroleum coke as activated carbon precursor was correlated with its physical properties. Super activated carbon (SAC) obtained from RPC exhibited very high specific surface area (3578m2g−1) with ultra-microporosity ranges from 0.4 to 0.7nm. The equilibrium adsorption of CO2, CH4, CO, and N2 measured on powder SAC at different temperatures evidenced its applicability for gas separation through high adsorption capacity and selectivity. SAC also showed the high fuel gas storage capacity, H2 (26.67mmolg−1 at 77K and 3000kPa) and CH4 (10.87mmolg−1 at 303K and 3700kPa) due to its high specific surface area and microporous textural property. The production of SAC was also demonstrated for pilot scale and examined for CH4 storage. The transformation of powder SAC into pellets using bentonite clay as a binder to provide better mechanical strength with enhanced CH4 adsorption (on a volume basis) made it viable for practical application.