Preparation of activated carbon from lignin by chemical activation

Activated carbons were prepared from lignin by chemical activation with ZnCl , H PO and some alkali metal 2 3 4 compounds. The influence of carbonization and activating reagent on the pore structure of the activated carbon was investigated. It was found that the maximum surface areas were obtained at the carbonization temperature of 6008C in both ZnCl and H PO activation, and that the surface areas were as large as those of the commercial activated carbons. On the 2 3 4 other hand, in alkali metal activation it was found that the maximum surface areas were obtained at the carbonization temperature of 8008C. Except for Na CO maximum surface areas were much larger than those of the commercial activated 2 3 2 carbons. The activated carbon prepared by K CO activation showed a surface area of nearly 2000 m / g. It was shown that 2 3 ZnCl works effectively as dehydration reagent below 6008C. On the other hand, K CO works effectively in two 2 2 3 temperature ranges, below 5008C and above 6008C. Below 5008C, the carbonization behavior was modified by impregnation with K CO , but the pore structure changes little. Above 6008C, carbon was consumed by K CO reduction and then the 2 3 2 3 surface area was increased.