核壳材料Co_(3)O_(4)@SiO_(2)催化环己基过氧化氢分解  

Decomposition of Cyclohexyl Hydroperoxide Catalyzed by Core-shell Material Co_(3)O_(4)@SiO_(2)

作　　者：陈小梅 陈颖 袁霞[1] CHEN Xiaomei;CHEN Ying;YUAN Xia(School of Chemical Engineering,Xiangtan University,Xiangtan 411105,China)

机构地区：[1]湘潭大学化工学院,湘潭411105

出　　处：《无机材料学报》2022年第1期65-71,共7页Journal of Inorganic Materials

基　　金：国家自然科学基金(21776237)。

摘　　要：环己基过氧化氢(CHHP)分解是环己烷无催化氧化工艺制备环己醇和环己酮的重要反应步骤。本研究以Co_(3)O_(4)纳米颗粒为内核,十六烷基三甲基溴化铵(CTAB)为模板剂,正硅酸四乙酯(TEOS)为硅源,采用模板法制备了核壳结构材料Co_(3)O_(4)@SiO_(2)。考察了SiO_(2)壳层制备条件:乙醇和水的比例、CTAB的浓度和TEOS的用量对核壳材料结构的影响。使用不同技术手段表征材料的结构特征,在CHHP分解反应中进行材料的催化性能评价和稳定性考察。结果表明,壳层薄且孔隙率高的材料催化性能更好,并且核壳结构可以减少钴元素的流失,催化材料在回收使用过程中出现了不同程度的壳层破碎现象。Decomposition of cyclohexyl hydroperoxide(CHHP)is an important step in the preparation of cyclohexanol and cyclohexanone by non-catalytic oxidation of cyclohexane.Using Co_(3)O_(4) nanoparticles as the core,cetyltrimethylammol/lonium bromide(CTAB)as the template and tetraethyl orthosilicate(TEOS)as the silicon source,the core-shell structure material Co_(3)O_(4)@SiO_(2) was synthesized by template method.The effects of the preparation conditions for SiO_(2) shells on the structure of core-shell material were investigated,such as the ratio of ethanol to water,the concentration of CTAB and the amount of TEOS.Textural properties of the materials were characterized by different techniques.Meanwhile,the catalytic performance and stability of the materials were evaluated on the decomposition reaction of CHHP.All results showed that the materials with thin shell and high porosity exhibited a preferable catalytic performance,and the conversion of CHHP was 81.68%and the selectivity of cyclohexanol and cyclohexanone was 70.60%and 34.06%,respectively.This core-shell structure could protect the activity of the core Co_(3)O_(4) and significantly decrease the loss of cobalt element.However,there existed different degree of the fragmentation of SiO_(2) shell in the recycling process of Co_(3)O_(4)@SiO_(2) samples.

关 键 词：核壳结构 Co_(3)O_(4)@SiO_(2) 环己基过氧化氢 分解 

分 类 号：O643[理学—物理化学]