CO-ACTIVATION OF PITCH-BASED CARBONMATERIALS IN MIXED SOLID AND GAS PHASES

摘要

The co-activation behavior of different carbon materia1s made from isotropic pitch and mesophase pitchsimultaneously in solid and gas phases has been studied. It was found that co-activatiorn in COCO2 + KOH had rnuch greatcreffect on thcse carbon materials than activation in COCO2 and in KOH alone. Compared to activaion in CO2 and inKOH ,co-ac-tivation in COCO2+KOH dramatically increased the reaction rates of the carbon materials studied as well as thevalues of weight loss and BET surface area which all followed the order SPCS > LPCS > GPCF >MPCF >HMPC>HMPCF. The apparent activation energies varied from 72.5KJ/mol to 119.8KJ/mol for the different carbon materials inco-activation. The co-activation behavior of the different carbon materials has been correlated with their crystallineparameters and microstructure. Carbonized fibers and spherules made from isotropic pitch are less resistant to activationand co-activation than those made from mesophase pitch. As evident from the X-ray data carbon materials made fromisotropic pitch have smaller La,Lc,and higher d002 values than mesophase pitch based carbon fibers. MPCF used inactivation and co-activation were found to possess skin-core type microtexture, while this microtexture was absent inHMPCF . The difference of the weight loss and the BET surface area between MPCF and HMPCF was due to thedifference in microtexture of MPCF and HMPCF.