Producing sawdust derived activated carbon by co-calcinations with limestone for enhanced Acid Orange II adsorption

Because of the widespread application of activated carbon (AC) as adsorbents, reduced production costs are highly desirable, therefore, inexpensive alternatives for activated carbon precursors and eco-procedures are presently sought. In this work, AC was successfully prepared from sawdust through co-calcinations with limestone. The surface area and porosity of the resulting ACs were evaluated according to the N2 adsorption at 77 K. Acid Orange II (AOII) was utilized as a negative dye to study the potential of the resulting AC as an adsorbent. Results revealed that the surface area and total pore volume were both increased greatly. When the activated carbon was prepared in mass ratios of 1:2 and 1:1 (calcium carbonate to sawdust), the surface area increased to 611.4 and 706.9 m2/g, respectively, and the adsorption capacities increased to 310.89 and 389 mg/g. These enhancements indicated efficient activation, resulting in energy-saving and environmentally friendly activated carbon production. Thus, this paper provides a cleaner process for producing activated carbon from waste sawdust through bioresource recycling.