Abstract
It is still a great challenge to develop a new porous carbon adsorbent with excellent separation performance and to recover low-concentration CH(4) in coal mine gas. This work provides a new idea for the study of CH(4) adsorption on activated carbon (AC) composites. Composite materials with microporous structures were prepared from coconut-shell activated carbon (CAC) doped with graphene oxide (GO) by a chemical activation process in this paper. The expansion and dissociation of GO at high temperatures indirectly improve the specific surface area (SSA) of the composite. The interlayer aggregation is reduced, the activation effect is improved, and a new low-cost adsorption material is prepared. The SSA of CAC-50 is more than 3000 m(2)·g(-1). A high SSA and a narrow pore size distribution lead to a higher total adsorption capacity of CH(4). The breakthrough test also confirmed that AC/GOs had a better adsorption capacity for CH(4). The separation performance of the CH(4)/N(2) mixture is not good at room temperature, which is due to the influence of a high SSA and average pore size. As a low-cost and rich material, CAC has a wide range of application prospects. The composite is a potential material for recovering low-concentration CH(4) from the coal mine, which is worthy of attention. In the future, the selectivity of AC/GOs to CH(4) can be increased by loading functional groups or modification.