Development of activated carbons from coal and biomass combustion and gasification chars

High carbon content chars, which are a byproduct stream from coal-fired combustors or gasifiers, are currently disposed as a waste. Due to the increasingly restricted landfill use, the utility industry needs to find uses for these chars. Following this demand, Zhang et al. have previously developed a one-step activation protocol to produce activated carbons from coal combustion chars. Compared to the conventional two-step process that includes a devolatilization of the raw materials, followed by an activation step, chars only require a one-step activation process, since they have already gone through a devolatilization process while in the combustor. The physical and chemical properties of coal and biomass chars derived form combustion and gasification processes, as well as their potential use as feedstock for activated carbons, were evaluated. This is an abstract of a paper presented at the 228th ACS National Meeting (Philadelphia, PA, 8/22-26/2004).