太原理工大学学报2017，Vol.48Issue(2)：156-162,7.DOI:10.16355/j.cnki.issn1007-9432tyut.2017.02.003
铜、锌摩尔比对Cu/ZnO前驱体和催化剂物相结构的影响
Effect of n(Cu)/n(Zn) Ratio on the Structure of Cu/ZnO Precursor and Catalyst
摘要
Abstract
The CuO/ZnO precursors and catalysts with different Cu/Zn atomic ratios (nCu/nZn) were obtained by traditional co-precipitation method.The microscopic properties of precursors and catalysts were further characterized through XRD,FT-IR,AAS and H2-TPR,with emphasis on the effect of the nCu/nZn on phase transition of precursors and dispersion of the catalysts.The results show that different concentration of Cu2+ and Zn2+ in raw material results in the difference between impetus of isomorphous substitution reaction and the formation energy of phase,thus controlling the phase composition of the precursor.When nCu/nZn＞75/25,the reactive impetus of the isomorphous substitution of Cu2+ in Cu2 (CO3) (OH)2 compound by Zn2+ is greater than the formation energy of (Cu1-x,Znx)2 (OH)2CO3 phase,the precursors contain pure (Cu1-x,Znx)2 (OH)2CO3 phase;When nCu/nZn≤40/60,the reactive impetus of Zn2+ substitution by Cu2+ in the Zn5 (CO3)2 (OH)6 phase exceeds the formation energy of (Zn1-x,Cux)5 (CO3)2 (OH)6 phase,and the precursors of single (Zn1-x,Cux)5 (CO3)2 (OH)6 phase can be gained;When 40/60＜nCu/nZn≤75/25,the precursors are consisted of (Cu,Zn)2 (OH)2CO3 and (Zn,Cu)5 (CO3)2 (OH)6.active CuO components are well dispersed in ZnO components after high-temperature calcination,thus having good dispersion and low reduction temperature.关键词
前驱体/晶相转变/同晶取代/推动力/形成能Key words
precursors/phase transition/isomorphous substitution/impetus/formation energy分类
化学化工引用本文复制引用
王立平,郑华艳,李忠,陈雄..铜、锌摩尔比对Cu/ZnO前驱体和催化剂物相结构的影响[J].太原理工大学学报,2017,48(2):156-162,7.基金项目
国家自然科学基金重点资助项目:合成气定向转化含氧化合物铜基催化剂的基础研究(U1510203) （U1510203）
国家自然科学基金资助项目:高比例Cu/Zn取代单物相前驱体及Cu/ZnO催化剂表面结构调控的基础研究(21576179) （21576179）
