Boosting the adsorption capacity of activated carbon prepared from Amygdalus communis shells using physicochemical co-activation method

Activated carbon is widely used in the production of high-performance capacitors and the removal of pollutants in water and gas due to its advantages such as well-developed pores and easy regeneration. However, the conventional single activation method limits the adsorption ability of activated carbon. Based on this, a physicochemical co-activation method was proposed to improve the adsorption performance of activated carbon. Firstly, single activated carbons were prepared from Amygdalus communis shells with CO 2 and ZnCl 2 as physical and chemical activators, respectively. The characterization results showed that compared with physical activation, the activated carbon prepared by chemical activation had more developed mesoporous structure, higher graphitization degree, and bulk porous structure, so the specific surface area and pore volume of the latter were higher. The adsorption capacity for methylene blue and iodine increased from 136.5 mg/g and 1046 mg/g to 148.5 mg/g and 1363 mg/g, respectively. Co-activation of CO 2 and ZnCl 2 further changed the pore structure of activated carbon, making activated carbon rich in micropore and mesopore structures. As a result, the specific surface area increased to 1711.83 m 2 /g, which significantly elevated the adsorption values of methylene blue and iodine to 210 mg/g and 1500 mg/g, respectively. The results of this study lay a theoretical foundation for the preparation of activated carbon with high adsorption performance.