不同干燥方式对SiO_(2)气凝胶物理性能的影响  

Influence of different drying methods on physical properties of SiO_(2) aerogel

作　　者：张鑫源 李淑敏 夏晨康 杨波 刘维海 尚阳 武泽民 陈欢乐 苗洋[1] 高峰[1] ZHANG Xin-yuan;LI Shu-min;XIA Chen-kang;YANG Bo;LIU Wei-hai;SHANG Yang;WU Ze-min;CHEN Huan-le;MIAO Yang;GAO Feng(School of Materials Science and Engineering,Taiyuan University of Technology,Taiyuan 030024,China;Research and Development Center of Nagu(Shanxi)Aerogel Innovation City Management Co.,Ltd.,Yangmei Group,Yangquan 045000,China)

机构地区：[1]太原理工大学材料科学与工程学院,山西太原030024 [2]阳煤集团纳谷(山西)气凝胶科创城管理有限责任公司研发中心,山西阳泉045000

出　　处：《应用化工》2022年第8期2300-2305,2310,共7页Applied Chemical Industry

基　　金：2021年度山西省重点研发计划项目(YK20002,202102030201006)。

摘　　要：选用廉价的水玻璃作为硅源,采用水玻璃滴加进盐酸的方式一步催化,探索溶胶-凝胶过程的工艺参数,并且对比常压干燥、冷冻干燥和超临界干燥对SiO_(2)气凝胶物理性能的影响,最终确定SiO_(2)气凝胶最佳制备工艺。采用BET、SEM、FTIR、XRD、ZETA等表征方法对样品进行分析。结果表明,当水玻璃和去离子水按体积比1∶4搅拌水解,在pH=4的条件下凝胶,是最佳凝胶条件。对比三种干燥方式,超临界干燥得到的SiO_(2)气凝胶的物理性能最好,比表面积为754.750 m^(2)/g,平均孔径为15.457 nm,总孔体积为3.160 cm^(3)/g,堆积密度为0.033 g/cm^(3),Zeta电位为-27.7 mV,热导率为0.0162 W/(m·K)。Cheap sodium silicate was selected as silicon source,and hydrochloric acid was added to sodium silicate as a one-step catalyst to explore sol-gel and modified process parameters,and compare the effects of atmospheric drying,freeze drying and supercritical drying on the physical properties of SiO_(2)aerogel,and finally determine the best preparation process of SiO_(2)aerogel.BET,SEM,FTIR,XRD,ZETA and other characterization methods were used to analyze the samples.The result showed that when the water glass and deionized water are stirred and hydrolyzed at a volume ratio of 1∶4,under the condition of pH=4 sol gel,is the best preparation condition.Compared with the three drying methods,the SiO_(2)aerogel obtained by supercritical drying has the best physical properties,with a specific surface area of 754.750 m^(2)/g,an average pore size of 15.457 nm,a total pore volume of 3.160 cm 3/g,a bulk density of 0.033 g/cm 3,Zeta potential of-27.7 mV,thermal conductivity 0.0162 W/(m·K).

关 键 词：水玻璃 气凝胶 超临界干燥 冷冻干燥 常压干燥 

分 类 号：TQ263[化学工程—有机化工]