Cocoa husks: a sustainable resource for alkali production

Abstract

Nigeria has no commercial alkali plant and most of her alkali requirements are imported. Thus the sustainability of using cocoa husks as resource for alkali production was investigated. Cocoa husks collected from three locations in Edo State; (CH1), (CH2) and (CH3) were separately burnt to ashes. Moisture content of ashes ranged from 72.25 ± 1.92% to 74.75 ± 4.11%, dry matter from 25.26 ± 4.11% to 27.76± 1.92 %, while ash content ranged from 20.29 ± 3.00% to 23.01 ± 3.71%. Alkali was extracted from the ashes by leaching with water at room temperature and CH1 had highest alkaline content (0.84± 0.01 M) while CH2 had the lowest (0.78± 0.02 M). Conductivity of the extract was 72.45± 0.03 s/m, 71.02± 0.02 s/m and 71.64± 0.01 s/m, while the pH was 11.655± 0.02 s/m, 11.40± 0.01 s/m and 11.42 ± 0.02 s/m respectively for CH1 CH2 and CH3. Metal analysis revealed that they contain appreciable potassium (CH1 = 43.54%, CH2= 41.15% and CH3= 41.67%) and sodium (CH1 = 34.78%, CH2 = 37.55% and CH3 = 34.86%) ions, thus can be used to generate alkali as alternative to foreign alkali, reduce Nigerian dependence on foreign alkali and providing environmental solution to their disposal problem.