Porous structure and adsorptive properties of activated carbon derived from Bambusa vulgaris striata by two-stage KOH/NaOH mixture activation for Hg2+ removal

Activated carbon with a large surface area was synthesized from Bambusa vulgaris striata via two-stage KOH/NaOH mixture activation. Functional properties of the produced activated carbon were investigated. Optimum conditions in activated carbon production were obtained from an impregnation ratio of char to KOH/NaOH mixture of 1:3 (w/w) at 800 °C, with a surface area and total pore volume of 1108 m2/g and 0.634 cm3/g, respectively. The optimized activated carbon was employed in mercury ion (Hg2+) adsorption through a continuous flow experiment at 25 °C. Its large surface area and pristine mineral elements were responsible for a high adsorption capacity of 312.7 mg/g. The results showed the superior feasibility of Bambusa vulgaris striata as a low-cost and abundant biomass precursor for the production of highly porous activated carbon that can be employed for Hg2+ removal. Hence, the produced activated carbon represents a promising adsorbent for the treatment of contaminated and polluted water as well as wastewater. [Display omitted] •Activated carbon (AC) was successfully produced using KOH/NaOH mixture.•AC showed high surface area and pore volume with dominantly microporous structure.•Thomas model was used to evaluate the properties of continuously Hg2+ adsorption.•312.7 mg of Hg2+/g of AC of maximum adsorption capacity were achieved.•Activation using hydroxide mixture produces high-grade AC for Hg2+ removal.