State Key Laboratory of Clean Energy Utilization, Zhejiang University
Qingshanhu Energy Research Center, Zhejiang University

氮掺杂活性炭制备过程中影响其性能的因素极其复杂,单一因素的定性分析无法满足对制备条件的准确调控,而多因素耦合量化分析可以弥补不足。以煤焦油沥青为原料,采用KOH活化法,与尿素共热解制备氮掺杂活性炭,通过响应曲面法(RSM)进行建模,以量化分析多因素耦合作用对活性炭产率和不同温度下(25℃,50℃和75℃)对CO2吸附性能的影响,同时优化制备工艺参数,并且在此实验设计基础上利用线性拟合方法预测不同温度下CO2吸附量的相关性。结果表明:对活性炭产率的影响由大到小的单因素依次为掺氮比(尿素与煤沥青的质量比)、活化温度、碱碳比(KOH与煤沥青的质量比)、活化时间,活化温度和活化时间的耦合作用影响最显著,碱碳比是影响活性炭CO2吸附量最为关键的因素,但随吸附温度升高其他因素影响显著性增强;不同温度下CO2吸附量可以进行相互预测,且相邻温度下CO2吸附量之间的预测效果更好;得到的最佳制备条件为活化温度650℃、活化时间1.25h、碱碳比2.5、掺氮比0.3,相应的活性炭产率可达59.316%,在25℃,50℃和75℃下CO2吸附量分别为3.474mmol/g,2.355mmol/g,1.358mmol/g。

The factors affecting the performance of nitrogen-doped activated carbon dur-ing its preparation process are extremely complex. The qualitative analysis of a single factor can-not satisfy the accurate control of preparation conditions, while the multi-factor coupled quantita-tive analysis can make up for the deficiency. In this study, with the help of KOH activationpitch), activation temperature, alkali-to-carbon ratio (mass ratio of KOH to coal tar pitch), acti-vation time, and the coupled effect of activation temperature and time is the most significant. The alkali-to-carbon ratio is the most critical factor affecting the CO2 adsorption capacity of the activated carbon. However, the significance of other factors increases notably with rising adsorp-tion temperatures. The CO2 adsorption capacities at different temperatures can be mutually pre-dicted, and the predictive effect between the CO2 adsorption capacities at adjacent temperatures is better. The optimum preparation conditions obtained are as follows: activation temperature of 650 ℃, activation time of 1.25 h, alkali-to-carbon ratio of 2.5, and nitrogen doping ratio of 0.3. Accordingly, the yield of activated carbon is 59.316%, and the CO2 adsorption capacities at 25 ℃, 50 ℃ and 75 ℃ are 3.474 mmol/g, 2.355 mmol/g and 1.358 mmol/g, respectively.

国家自然科学基金项目(U1910201)和中央高校基本科研业务费项目(2022ZFJH04).

黄 玉,方梦祥,余 鹏,等.基于响应曲面法优化氮掺杂活性炭的制备和 CO2 吸附性能研究[J].煤炭转化,2024,47(1):49-59

HUANG Yu,FANG Mengxiang,YU Peng,et al.Optimization of preparation of nitrogen-doped activated carbon and CO2 adsorption prop-erty based on response surface methodology[J].Coal Conversion,2024,47(1):49-59