Coffee residue-based activated carbons for phenol removal

This work was aimed to evaluate the adsorptive properties of activated carbons from coffee residue for phenol removal. The coffee residue was activated using H3PO4 and KOH, and the resultant activated carbons were characterized for surface area and functional groups. The values of surface area were recorded as 1,030 m(2)/g and 399 m(2)/g for H3PO4- and KOH-activated carbons, respectively. The maximum capacity for phenol removal is comparable for both activated carbons at 43 mg/g. The pores might be inaccessible due to electrostatic repulsion by surface functional groups and hydroxyl anions. The second stage in a two-stage adsorber design is necessary to accomplish the process with high performance and minimum dosage of activated carbon. Coffee residue is a promising activated carbon precursor for phenol removal.

Automated summary

The study evaluates the adsorptive properties of activated carbons from coffee residue for phenol removal, with comparable maximum capacity for both H3PO4- and KOH-activated carbons. However, the presence of surface functional groups and hydroxyl anions may hinder pore accessibility, necessitating a two-stage adsorber design for high performance and minimal activated carbon dosage. Coffee residue shows promise as a precursor for phenol removal with activated carbon.