Chemical activation of biochar derived from coffee husk for the adsorption of phytohormones from waste coconut water

Abstract The potential of NaOH-activated biochar derived from waste coffee husks via pyrolysis for the extraction of phytohormones from waste coconut water was investigated. The raw coffee husk biochar (CHB) and coffee husk activated biochar (CHAB) were characterized and compared in terms of morphology, particle size distribution, elemental composition, surface functional groups, bulk density, phytohormone adsorption efficiency and equilibrium adsorption capacity. The phytohormone adsorption efficiency of the CHB and CHAB produced were 62.36% and 91.33%, respectively. Future work includes flask adsorption experiments and using the phytohormone content extracted from the coconut water for tissue culture studies. Collectively, results from this study present an alternative use of coconut and coffee wastes, and ultimately contribute to the waste management processes of the coconut and coffee industries.