煤质成分对煤基活性炭活化成孔的影响机制

Influence Mechanism of Coal Composition on Activation Pore Formation of Coal-Based Activated Carbon

以国内常用的8种煤为原料,在相同工艺下,采用KOH活化制备煤基活性炭.利用低温N2吸附、电子扫描电镜(SEM)等手段对活性炭表面的孔结构及表面形貌进行表征,考察原料煤的物理化学性质对煤基活性炭活化成孔的影响机制以及对表面孔隙结构的影响规律.结果表明,原料煤的原生孔隙、挥发分及固定碳有利于活性炭自身的微孔发展;而原料煤的含水量以及灰分含量和固定碳中不可活化的未分解碳氢物质会抑制活化成孔.最终制备出比表面积为546~978 m^2/g、总孔容为0.32~0.57 cm^3/g的活性炭。

Eight kinds of coal commonly used in China were taken as raw materials,and KOH activation was adopted to prepare coal-based activated carbon by the same process.The pore structure and surface morphology of activated carbon were characterized by low temperature N2 adsorption and electron scanning electron microscopy(SEM),and the influencing mechanisms of physical and chemical properties of raw coal on the activation pore formation of coal-based activated carbon and the surface pore structure were investigated.The results show that the primary porosity,volatile fraction and fixed carbon of raw coal are beneficial to the development of activated carbon micropores.However,the water content and ash content of raw coal and the inactivated undecomposed hydrocarbon in fixed carbon inhibit the activation of pore formation.Finally,the specific surface area and the total pore volume of the activated carbon prepared in this paper were 546—978 m^2/g and 0.32—0.57 cm^3/g respectively.