摘要
以介孔SiO2分子筛MCM-41为研究对象,以蔗糖为碳源,采用浸渍法制备C/MCM-41,在管式炉中氩气氛围下进行热处理,研究高温下碳对介孔SiO2转晶的影响,并通过X射线衍射(XRD)、热重(TG)、N2物理吸附脱附等对样品的物相和织构性质进行分析.结果表明,碳的存在对MCM-41的孔道可以起到支撑作用,但同时抑制了SiO2从无定形向晶型的转变,且随着碳填充量的增加,转晶温度呈升高趋势,这归因于碳的存在阻碍了Si、O原子的扩散,提高了方石成核临界尺寸的温度.
Influence of carbon on phase transformation of mesoporous silica was investigated in Ar atmosphere under different temperatures from 800-1500℃.The pores of mesoporous molecular sieves in MCM-41 were filled with carbon,to obtain C/MCM-41.The physicochemical properties of this materials were characterized with X-ray diffraction(XRD),thermogravimetry(TG),and N2 physical sorption.The presence of carbon was found to play a supporting role in mesoporous structure?But silica transformation from amorphous to crystalline forms was inhibited.With increasing carbon filling,temperature of crystalline transition increased,therefore the existence of carbon hindered diffusion of Si and O atoms,making the cristobalite fail to reach a critical size of nucleation.
作者
郭妮亚
张晔
林明桂
王俊刚
侯博
李德宝
GUO Niya;ZHANG Ye;LIN Minggui;WANG Jungang;HOU Bo;LI Debao(State Key Laboratory of Coal Conversion,Institute of Coal Chemistry,Chinese Academy of Sciences,030001,Taiyuan,Shanxi,China;University of Chinese Academy of Sciences,100049,Beijing,China;Dalian National Laboratory for Clean*Energy 116023,Dalian,Liaoning,China)
出处
《北京师范大学学报（自然科学版）》
CAS
CSCD
北大核心
2019年第4期462-467,共6页
Journal of Beijing Normal University(Natural Science)
基金
中国科学院战略性先导科技专项基金资助项目(XDA21020202)
关键词
转晶
热处理
介孔分子筛
C/MCM-41
phase transformation
heat treatment
mesoporous silica
carbon-filled MCM-41
