褐煤基活性炭的制备及其电化学性能研究  

Preparation and electrochemical properties of lignite-based activated carbon

作　　者：续士勇 岳劲松 程园 程嗣丹 丁宁 李梅[1,2,3] XU Shiyong;YUE Jinsong;CHENG Yuan;CHENG Sidan;DING Ning;LI Mei(School of Chemistry and Chemical Engineering,North Minzu University,750021 Yinchuan,China;Ningxia Key Laboratory of Solar Chemical Conversion Technology,North Minzu University,750021 Yinchuan,China;Key Laboratory for Chemical Engineering and Technology,State Ethnic Affairs Commission,North Minzu University,750021 Yinchuan,China)

机构地区：[1]北方民族大学化学与化学工程学院,银川750021 [2]北方民族大学宁夏太阳能化学转化技术重点实验室,银川750021 [3]北方民族大学国家民委化工技术基础重点实验室,银川750021

出　　处：《煤炭转化》2023年第1期62-71,共10页Coal Conversion

基　　金：国家自然科学基金资助项目(21666001);北方民族大学研究生创新项目(YCX22169)。

摘　　要：以HCl-HF法脱矿物质处理后的云南莲花塘褐煤和内蒙古白音华褐煤以及这两种褐煤所制备的半焦为原料,将原料以KOH为活化剂的化学活化法制备活性炭,考察KOH用量和炭化终温对煤基活性炭比表面积、孔径分布及孔体积的影响。利用X射线衍射仪(XRD)、比表面积与孔隙分析仪(BET)、扫描电子显微镜(SEM)和X射线光电子能谱仪(XPS)等测试手段表征活性炭的结构及表面性质。利用电化学工作站对活性炭电极进行循环伏安特性(CV)、交流阻抗特性(EIS)和充放电特性(GCD)分析,利用蓝电电池测试系统测试扣式电容器的电容保持率。结果表明:采用脱矿物质处理后的褐煤为原料,以KOH为活化剂的化学活化法,碱煤质量比为4∶1,炭化终温为800℃的条件下制备的活性炭的比表面积和孔体积最大;在此工艺条件下,莲花塘褐煤基活性炭的比表面积为2728 m^(3)/g,孔体积为1.58 cm^(3)/g,白音华褐煤基活性炭的比表面积为1824 m^(3)/g,孔体积为1.00 cm^(3)/g;将这两种活性炭作为电极材料,所制备的活性炭电极在电流密度为1 A/g时,比电容分别为246 F/g和244 F/g,在电流密度为20 A/g时,比电容分别为205 F/g和202 F/g,比电容下降率分别为16.7%和17.2%,表现出良好的高倍率特性;在1 A/g的电流密度下测试所制备的扣式电容器,经8000次循环后的比电容保持率达99.87%,体现出褐煤基活性炭良好的电化学性能。Activated carbon was prepared by chemical activation method using HCl-HF demineralized Yunnan Lianhuatang lignite and Inner Mongolia Baiyinhua lignite and semi-coke from these two kinds of lignite as raw materials with KOH as an activator,and the effects of KOH dosage and carbonization end temperature on the specific surface area,pore size distribution and pore volume of coal-based activated carbon were investigated.The structure and surface properties of the activated carbon were characterized by X-ray diffraction(XRD),specific surface area and porosity analyzer(BET),scanning electrol microscope(SEM)and X-ray photoelectron spectroscopy(XPS).The cyclic voltammetric characteristics(CV),AC impedance characteristics(EIS)and charge-discharge characteristics(GCD)of the activated carbon electrodes were analyzed using an electrochemical workstation.The capacitance retention of the buckle capacitors was tested using a blue battery test system.The results show that the activated carbon prepared by the chemical activation method using lignite as the raw material and KOH as the activator with the mass ratio of alkali to coal is 4∶1 and the final carbonization temperature of 800℃has the largest specific surface area and pore volume.Under this process,the specific surface area of Lianhuatang lignite-based activated carbon is 2728 m^(2)/g and the pore volume is 1.58 cm^(3)/g;the specific surface area of Baiyinhua lignite-based activated carbon is 1824 m^(2)/g and the pore volume is 1.00 cm^(3)/g.Using these two activated carbons as electrode materials,it is found that the specific capacitance of the prepared activated carbon electrodes is 246 F/g and 244 F/g at a current density of 1 A/g.The specific capacitance reaches 205 F/g and 202 F/g at a current density of 20 A/g,with a decrease in specific capacitance of 16.7%and 17.2%,respectively,showing good high multiplicity characteristics.After 8000 cycles,the specific capacitance retention rate of the prepared buckle capacitor reaches 99.87%at a current density of 1 A/g,whic

关 键 词：褐煤 半焦 活性炭 孔结构 电化学性能 

分 类 号：TQ424.1[化学工程]