CO_2活化木屑炭制备活性炭及工艺优化

以炼制生物质油过程中产生的木屑炭为原料,CO2为活化气体,通过物理活化法制备活性炭。考察了活化温度、活化时间及CO2流量对活性炭亚甲基蓝吸附值的影响。采用中心组合实验,运用响应曲面进行工艺参数优化,得出最佳的工艺参数为活化温度850℃,活化时间3.91h,活化气体流量30ml/min,此时由软件预测的亚甲基蓝吸附值为10.66ml/0.1g,得率42.66%,经验证,与实际相符。并对模型进行了检验,验证了其有效性。并选择不同温度下制备活性炭进行N2吸附脱附等温线实验,得到所制备活性炭BET最大可达948m2/g,由BJH理论分可知其中孔比表面积为296m2/g,平均孔径为3.76nm。

Preparation and Process Optimization of Activated Carbon Made of Sawdust Charcoal by CO2 Activation

Activated carbon was prepared by physical was by-product from the process of refining biomass oil. activation with carbon dioxide from sawdust carbon, which The influence of activation temperature, activation time and the flow rate of CO2 on the methylene blue value of activated carbon were investigated. Based on the experimental optimization methods including the central composite design and the response surface methodology, the optimized process parameters were found that the activation temperature be 850 ℃, the activation time be 3.91h and the gas flow rate be 30 ml/min. They were proved to be consistent with the prediction results of the model, which adsorp- tion of the methylene blue value was 10. 66 mL/0. lg, and the yield of activated carbon was 42. 66%. The model was tested to verify its effectiveness. Besides, the N2 adsorption - desorption isotherms experiment of activated car- bon preparation under the different temperature were conducted. The maximum BET was 948 m2/g. The mesopore specific surface area was 296 m2/g and the average pore size was 3.76 nm, according to the BJI-I theory.