Characterization of Coconut Shell Activated Carbon Obtained from By-product of Preparation Process of Bio-oil with Fast Pyrolysis

摘要

A new process was investigated which combines both fast pyrolysis carbonization and CS activated carbons with H_3PO_4 activation (CSAC). ACs were obtained as by-product from the preparation process of bio-oil with fast pyrolysis under different temperatures (T=727-973 K), in which the reaction ended in a very short duration. A two-step process of reaction is proposed to govern carbonization and activation: firstly fast pyrolysis reaction removing disorganized material was associated with considerable weight loss but with low generation of porosity, pyrolysis/carbonization under the flow of N_2 is suggested to ensure fluidization of CS powders and bed material, enhance decomposition of raw material, initiates controlled gasification at different temperatures. Then H_3PO_4 activation process dominated at 573 K, which leads to considerable evolution of porosity. In this research, the adsorption characteristics were determined from N_2 adsorption isotherms and subsequent analysised by the BET-and BJH-methods. As a result, the iodine adsorption number of AC was 1310 mg/g and the SSA of AC was 1421.38 m~2/g.