Activated carbons from cocoa pod husks under chemical activation with H3PO4 : effect of CO2 as oxidizing agent

Cocoa pod husk (CPH) is a by-product from cocoa plantation. This by-product with proper treatment has potential to be turn value added products. In this study, CPH are the raw material for the production of activated carbon. Response surface methodology (RSM) was applied to understand the effects of H3PO4 pre-treatment (0, 20, 40%), activation temperature (500, 600, 700°C) and CO2 exposure (0.5, 1, 1.5 hr) as oxidizing agent. The highest activated carbon yield is at 68% where the cocoa pod husk was pre-treated with 40% H3PO4 and activation temperature are between 500-550°C for 72.60 min in CO2 stream. The oxidation treatment with CO2 process also improves the methylene blue adsorption and CU2+ adsorption capacity.