Mass Balance and Quality Assessment of Potash from Cocoa Husk Ash from Ghana

Emmanuel Awarikabey, Mark Brako Frempong Berko, Emmanuela Kwao-Boateng, Martin Yeboah Woode, Andrew Nyamful, Eric Enzula Bayari, Eric Selorm Agorku

Abstract: The study assesses the mass balance and quality of potash produced from cocoa husk ash from Ghana. Potassium salt was produced by combusting dry cocoa husk to ash and mixing the ash with deionized water, filtering and evaporating the filtrate to dryness. The quantity of potassium carbonate present in the potassium salt was 98.4 % on dry basis. Multielement analysis using ICP/OES indicates elevated elements concentration for boron (140 mg/kg), calcium (170 mg/kg), sodium (140 mg/kg), silicon (180 mg/kg), strontium (2.2 mg/kg), molybdenum (4 mg/kg) and phosphorus (2400 mg/kg) but Ag, Al, As, Ba, Be, Bi, Cd, Co, Cr, Cu, Fe, Li, Mg, Mn, Ni, Pb, Sb were below detection limit. The material balance based on previous work suggests the following ratio: 124 (fresh cocoa husk): 25 (dry cocoa husk): 2 (Ash): 1 (potassium salt) which serve as a quick estimate for any prospective cocoa husk potash industry. The quality of the potassium salt provides an unusually very high amount of potassium (560, 000 mg/kg) present in the potassium salt, making the ash very useful feedstock for the potash industry.

Keywords: Ash, Potash, Potassium Carbonate, Cocoa Husk