Waste bamboo‐derived biochar and multiporous carbon as adsorbents for methyl orange removal

Abstract Materials Multiporous carbon (MPC) with a high specific surface area (1121 m 2 g −1 ) and mesoporous and microporous structures was prepared by using bamboo biochar (308 m 2 g −1 ) as raw material. Methods The preparation involved a CaCO 3 activation process, where CaCO 3 served as both the template for mesopores and the activating agent for micropores. The template could be easily removed by dilute HCl (aq) solution, making the preparation process simpler and more environmentally friendly compared to using mesoporous SiO 2 as a hard template. Results The performance of the MPC and biochar as adsorbents for methyl orange (MO) dye was investigated by means of thermal dynamic isotherms and kinetic models tests. The Langmuir isothermal analysis results revealed that the MPC exhibited a significantly higher MO adsorption capacity (344.8 mg g −1 ) compared to the bamboo biochar (12.4 mg g −1 ). The adsorption kinetics of the MPC followed a pseudo‐second‐order model. Conclusion Overall, the obtained MPC material offers a cost‐effective, environmentally friendly, and efficient solution for removing dyes from aqueous solutions.