无硫可膨胀石墨的制备及特征  

Preparation and characterization of sulfur-free expansible graphite

作　　者：安峰文 罗立群[1,2] 刘斌[1,2] 孙伟[1,2] 温欣宇 田金星[1,2] 

机构地区：[1]武汉理工大学资源与环境工程学院,湖北武汉430070 [2]矿物资源加工与环境湖北省重点实验室,湖北武汉430070

出　　处：《现代化工》2017年第4期75-79,共5页Modern Chemical Industry

基　　金：国家科技支撑计划项目(2013BAE04B03)

摘　　要：以内蒙古固定碳质量分数为98.86%的天然鳞片石墨为原料,高锰酸钾、硝酸与高氯酸的混酸为氧化插层剂,采用化学氧化法直接插层制备可膨胀石墨。探究混酸配比(质量比)及用量、高锰酸钾质量分数、反应温度、反应时间等因素对可膨胀石墨膨化效果的影响。最佳制备工艺条件为:m(石墨)∶m(高锰酸钾)∶m(混酸)为1∶0.10∶4.5,混酸中硝酸的质量分数为8%,反应温度为40℃,反应时间为45 min,此条件下制得的可膨胀石墨的膨胀容积为410 m L/g。各阶段产物的XRD、FTIR、SEM分析表明,插层后碳层边缘呈现卷曲、张裂和剥离,层间距增大,膨胀后形成独特的"微胞"蠕虫状、贯通柳叶状、不规则多边形的三级孔隙结构。The natural flake graphite with 98. 86% of carbon content and plus 0. 30 mm（ plus 50 mesh） of size in Inner Mongolia Autonomous Region is taken as raw material. Sulfur-free expansible graphite is prepared then by chemical oxidization method with potassium permanganate,the mixture of nitric and perchloric acid as oxidant and intercalation agents. The effects of reaction conditions on the expansion volume are studied,including quantity of potassium permanganate,the ratio of mixed acid,reaction temperature and reaction time. The results show that the best expansion volume of expansible graphite is up to 410 m L/g under the following conditions： 1 ： 0. 10 ： 4. 5 mass ratio of graphite：potassium permanganate∶ mixed acid,8% of nitric acid in the mixed acid,40℃ of reaction temperature and 45 min of reaction time. The characteristics of each stage of the products are determined by XRD and SEM. The results show that graphite edges present curled,cracked and exfoliation and the interlayer distance is increased after intercalation.Exfoliated graphite has displayed three-stage unique micropore structures,in which ‘micro bubble ＇ like connected wormlike,willow leaf shape and micropore structure of irregular polygon ae detected by XRD,FTIR and SEM techniques.

关 键 词：可膨胀石墨 插层剂 化学氧化法 微孔特征 

分 类 号：TD97[矿业工程—选矿] TQ127.1[化学工程—无机化工]