Demineralization of Hainan coconut shell and its residue for preparing high surface area activated carbon
As raw materials for preparing high surface area activated carbon(HSAAC), there are distinct differences between coconut shell and petroleum coak.For preparing high quality HSAAC, coconut shell and its residue must be demineralized.The result of orthogonal test indicated that the ash content of coconut shell and its residue treated under optimal conditions of 10% H_3PO_4 and 3h at room temperature,could be decreased to 0.42% and 0.75%,respectively.After improving the process of coconut shell acid hydrolyzation, the ash content of coconut shell residue could be decreased to 0.40%.Therefore, they can be excellent raw materials for preparing HSAAC.After the products were treated with acid, the iodine number of the products made from these materials increased by 9% and the specific surface area of the products could be also increased by 11% via floatation to remove free ash.