FeCl_3对准东煤基多孔碳孔隙结构与石墨化协同调控  

Synergistic Effect of FeCl_3 on Pore-Structure and Crystallization of Zhundong Coal-based Activated Carbons

作　　者：王丽杰[1] 孙飞[1] 刘冬冬[1] 皮信信[1] 杨玉奇[1] 高继慧[1] WANG Li-Jie SUN Fei LIU Dong-Dong PI Xin-Xin YANG Yu-Qi GAO Ji-Hui(School of Energy Science and Engineering, Harbin Institute of Technology, Harbin 150001, China)

机构地区：[1]哈尔滨工业大学能源科学与工程学院,哈尔滨150001

出　　处：《工程热物理学报》2017年第8期1777-1783,共7页Journal of Engineering Thermophysics

基　　金：国家自然科学基金资助项目(No.51134015;No.51276052)

摘　　要：多孔碳制备过程中,孔结构的发展和石墨化的演变相互依存,且高的石墨化度往往导致孔隙结构衰减。为同时提高煤基多孔碳孔隙结构与石墨化程度,本文以我国大储量准东煤为原料,通过添加FeCl_3实现孔隙结构与石墨化度的协同调控,探究不同FeCl_3添加量的影响。结果表明:随着FeCl_3添加量增加,煤焦比表面积由346 m^2·g^(-1)增加到574m^2·g^(-1);石墨化程度逐渐增加,I_G/I_(All)由8.774%增加到9.328%。通过分析得出:FeCl_3水解及热解作用产生的铁氧化物与热解、活化过程产生的CO反应原位形成CO_2,对煤焦刻蚀,促进微孔的发展;煤焦中无定型碳与还原性Fe形成Fe_3C中间相,在碳不断"溶解析出"过程实现了催化石墨化的进行;酸洗过程释放了一部分中孔。由此可见,FeCl_3同时起着微孔造孔剂、中孔模板剂及催化石墨化促进剂的作用。In the preparing processes of porous carbon, the development of porous structure was highly related to the evolution of graphitic crystalline structure. Meanwhile, the porous structure will be collapse as the crystallinity increases. Development of porous with both high surface area and graphitization degree has attracted considerable research attention in the fields of gas adsorption and electrochemical energy storage. With the assistant of CO2 atmosphere, porous carbons can be one-step synthesized by using the FeCla.6H20 and low-cost Chinese Zhundong coal as the metal and carbon precursor, respectively. As a result, with the increase of FeC13 addition, the surface area increased from 346 m^2.g^-1 to 574 m^2·g^-1. Besides, the graphitization degree improved simultaneously with IG/IAll increasing from 8.774% to 9.328%. Through the analysis, CO2 can be in situ generated by using iron oxides derived from the hydrolysis-pyrolysis of FeC13.6H20 and CO from the pyrolysis- activation processes, and etch the carbon-based coal framework to create micropore. Fe3C could be generated by the reaction between amorphous carbon and reductant Fe. Accompanied by the carbon dissolution- precipitation procedure, graphitization degree has be improved. Meanwhile, some mesopore could be released in pickling process. In general, FeC13 was template and activation agent, and has catalytic effect of graphitization.

关 键 词：FECL3 准东煤 孔隙结构 石墨化度 协同调控 

分 类 号：TK019[动力工程及工程热物理]