兰炭末水蒸气活化制备活性炭过程中反应温度的影响

Effects of Reaction Temperature on Preparation of Activated Carbon by Steam Activation from Blue-coke Powder

以粒度为2.0mm^3.2mm的兰炭末为原料,采用水蒸气高温活化法制备颗粒活性炭,研究活化温度对活性炭结构与性能的影响,阐述活化过程中活性炭孔结构的形成机理,并利用SEM和全自动吸附仪对活性炭的表面形貌、比表面积和孔结构等进行分析表征.结果表明:随着活化温度的升高,活性炭的收率持续减小,碘吸附值呈现先增大后减小的趋势.当活化温度为900℃时,活性炭的收率为59.81%,其碘吸附值最大可达到812.86mg/g,BET比表面积和孔容分别为529.66m^2/g和0.298 9cm^3/g.当活化温度为600℃时,水蒸气活化过程以通孔作用为主导,700℃~800℃时为造孔阶段,而800℃~1 000℃范围内主要进行扩孔反应.

Granular activated carbon was prepared by steam-activated high-temperature method using blue-coke powder with particle size of 2.0mm-3.2mm as raw material.The effects of activation temperature on the structure and properties of activated carbon were studied and the formation mechanism of pore structure of activated carbon was discussed.The surface morphology,specific surface area and pore structure of activated carbon were characterized by SEM and automatic adsorption apparatus.The results show that with the increase of the activation temperature,the yield of activated carbon continue to decrease,and the iodine adsorption value increases first and then decreases.When the activation temperature is 900℃,the yield of activated carbon is 59.81%,the iodine adsorption value is 812.86mg/g,the BET specific surface area is 529.66m^2/g,and the pore volume is 0.298 9cm^3/g.The steam activation process is dominated by through-hole when the activation temperature is 600 ℃.The pore-forming stage is at 700 ℃-800℃,and the hole-expanding reaction is mainly carriy out at 800 ℃-1 000 ℃.