蒸氨压力对Cu/SiO2催化剂的影响及其草酸二甲酯加氢性能

doi:10.11944/j.issn.1000-0518.2016.04.150288

摘要/Abstract

摘要：

以SiO₂为载体,铜氨溶液为前驱体,采用蒸氨法在不同蒸氨压力下制备了系列铜负载量质量分数为20.0%的Cu/SiO₂催化剂。采用X射线衍射(XRD)、H₂-程序升温还(H₂-TPR)、高分辨透射电子显微镜(HRTEM)、X射线诱导俄歇电子能谱(XAES)等技术手段对催化剂的物理化学性能进行了表征。考察了蒸氨速率对催化剂物化结构及其草酸二甲酯催化加氢制乙二醇的催化性能影响。在反应温度 200 ℃、压力3.0 MPa、液时空速LHSV=0.4 h^-1、氢气草酸二甲酯摩尔比80:1的反应条件下测定了催化剂的活性。结果表明,在蒸氨压力为31.3 kPa条件下制备的催化剂表现出了最佳活性和选择性,草酸二甲酯转化率达到了99.9%,乙二醇选择性达94.4%。 H₂-TPR、XRD、TEM、FTIR及XAES表征结果表明,较低蒸氨压力有利于铜氨离子快速分解负载在载体上,避免铜粒子聚集长大,还原后形成Cu₂O和Cu⁰物种颗粒尺寸较小,分散比较均匀,催化活性,尤其是乙二醇的选择性更佳。

关键词: 蒸氨压力, Cu/SiO₂催化剂, 草酸二甲酯加氢

Abstract:

A series of Cu/SiO₂ catalysts with 20.0% mass fraction of Cu loading was prepared by the ammonia evaporation method using SiO₂ as the support and Cu(NH₃)₄²⁺ aqueous solutions as the precursor. The catalysts were characterized through X-ray diffraction(XRD), H₂-temperaure programmed reduction(H₂-TPR), transmission electronic microscopy(TEM) and X-ray Auger spectra(XAES) to investigate the influence of the ammonia evaporation rate on the catalyst physical and chemical structure and its catalytic performance for the hydrogenation of dimethyl oxalate(DMO) to ethylene glycol(EG). The catalytic activity measurement experiments were performed under working conditions of 200 ℃, p=3.0 MPa, LHSV=0.4 h^-1 and the molar ratio of hydrogen to DMO(n(H₂):n(DMO)=80:1). The results indicate that the catalyst prepared under high vacuum during ammonia evaporation has better catalytic performance. For the catalyst prepared under ammonia evaporation pressure of 31.3 kPa, 99.9% conversion of DMO and 94.4% selectivity to EG are obtained. Characterizations through XRD, H₂-TPR, TEM and XAES suggest that the higher the ammonia evaporation rate, the faster and more uniform distribution of copper precursors upon the SiO₂ support, and the coagulation and growth of the Cu particles during calcination and reduction can be reduced, which guarantees the high catalytic activity, particularly the selectivity to EG.

Key words: ammonia evaporation pressure, Cu/SiO₂ catalysts, hydrogenation of dimethyl oxalate

丁丁, 王琪, 金方, 陈亚中, 崔鹏, 刘荣, 沈浩. 蒸氨压力对Cu/SiO₂催化剂的影响及其草酸二甲酯加氢性能[J]. 应用化学, 2016, 33(4): 466-472.

DING Ding, WANG Qi, JIN Fang, CHEN Yazhong, CUI Peng, LIU Rong, SHEN Hao. Influences of the Ammonia Evaporation Pressure on the Structure of Cu/SiO₂ Catalysts and Catalytic Performances for Dimethyl Oxalate Hydrogenation to Ethylene Glycol[J]. Chinese Journal of Applied Chemistry, 2016, 33(4): 466-472.

参考文献

[1]	HUANG Gesheng,LI Zhenyu,LI Dingjie,et al.Analysis of Current Technologies and Prospects of Ethanediol Produced from Oil and Coal[J]. Chem Ind Eng Prog,2011,30(7):1461-1465(in Chinese). 黄格省,李振宇,李顶杰,等. 石油和煤生产乙二醇技术现状及产业前景分析[J]. 化工进展,2011,30(7):1461-1465.
[2]	SONG Heyuan,JIN Ronghua,KANG Meirong,et al.Progress in Synthesis of Ethylene Glycol through C1 Chemical Industry Routes[J]. Chinese J Catal,2013,34(6):1035-1050(in Chinese). 宋河远,靳荣华,康美荣,等. 碳一化工路线制备乙二醇研究进展[J]. 催化学报,2013,34(6):1035-1050.
[3]	LIN Ling,PAN Pengwu,ZHOU Zhangfeng,et al.Cu/SiO2 Catalysts Prepared by the Sol-Gel Method for Hydrogenation of Dimethyl Oxalate to Ethylene Glycol[J]. Chinese J Catal,2011,32(S6/7/8):957-969(in Chinese). 林凌,潘鹏武,周张峰,等. 溶胶凝胶法制备的Cu/SiO2催化剂及其催化草酸二甲酯加氢反应[J]. 催化学报,2011,32(S6/7/8):957-969.
[4]	WANG Baowei,ZHANG Xu,XU Qian,et al.Preparation and Characterization of Cu/SiO2 Catalyst and Its Catalytic Activity for Hydrogenation of Diethyl Oxalate to Ethylene Glycol[J]. Chinese J Catal,2008,29(3):275-280(in Chinese). 王保伟,张旭,许茜,等. Cu/SiO2催化剂的制备、表征及其对草酸二乙酯加氢制乙二醇的催化性能[J]. 催化学报,2008,29(3):275-280.
[5]	Chen L F,Guo P J,Qiao M H,et al.Cu/SiO2 Catalysts Prepared by the Ammonia-evaporation Method:Texture, Structure and Catalytic Performance in Hydrogenation of Dimethyl Oxalate to Ethylene Glycol[J]. J Catal,2008,257(1):172-180.
[6]	LI Zhenhua,XU Genhui,WANG Haijing,et al.Effect of the Preparation of Cu-based Catalyst on the Hydrogenation of Diethyl Oxlate[J]. Chinese J Catal,1995,16(1):9-14(in Chinese). 李振花,许根慧,王海京,等. 铜基催化剂的制备方法对草酸二乙酯加氢反应的影响[J]. 催化学报,1995,16(1):9-14.
[7]	Zhao S,Yue H R,Zhao Y J,et al.Chemoselective Synthesis of Ethanol via Hydrogenation of Dimethyl Oxalate on Cu/SiO2:Enhanced Stability with Boron Dopant[J]. J Catal,2013,297(1):142-150.
[8]	Ma X B,Chi H W,Yue H R,et al.Hydrogenation of Dimethyl Oxalate to Ethylene Glycol over Mesoporous Cu-MCM-41 Catalysts[J]. AIChE J,2013,59(7):2530-2539.
[9]	Zhao L,Zhao Y J,Wang S P,et al.Hydrogenation of Dimethyl Oxalate Using Extruded Cu/SiO2 Catalysts:Mechanical Strength and Catalytic Performance[J]. Ind Eng Chem Res,2012,51(43):13935-13943.
[10]	Chen L Y,Horiuchi T,Osaki T,et al.Catalytic Selective Reduction of NO with Propylene over Cu-Al2O3 Catalysts:Influence of Catalyst Preparation Method[J] Appl Catal B,1999,23(4):259-269.
[11]	Marchi A J,Fierro J L G,Santamaria J, et al. Dehydrogenation of Isopropylic Alcholol on a Cu/SiO2 Catalyst:A Study of the Activity Evolution and Reactivation of the Catalyst[J]. Appl Catal A,1996,142(2):375-386.
[12]	Li F,Lu C S,Li X N. The Effect of the Amount of Ammonia on the Cu0/Cu+ Ratio of Cu/SiO2 Catalyst for the Hydrogenation of Dimethyl Oxalate to Ethylene Glycol[J]. Chinese Chem Lett,2014,25(11):461-1465.
[13]	Yin A Y,Guo X Y,Dai W L,et al.Highly Active and Selective Copper-containing HMS Catalyst in the Hydrogenation of Dimethyl Oxalate to Ethylene Glycol[J]. Appl Catal A,2008,349(s1/2):91-99.
[14]	Zhao S,Yue H R,Zhao Y J,et al.Chemoselective Synthesis of Ethanol via Hydrogenation of Dimethyl Oxalate on Cu/SiO2:Enhanced Stability with Boron Dopant[J]. J Catal,2013,297(1):142-150.
[15]	LI Zhuxia,QIAN Zhigang,ZHAO Xiuge,et al.Effect of Supports on Copper-Based Catalysts for Dimethyl Oxalates Hydrogenation[J]. J East China Univ Sci Technol(Nat Sci Ed)),2005,31:27-30(in Chinese). 李竹霞,钱志刚,赵秀阁,等. 载体对草酸二甲酯加氢铜基催化剂的影响[J]. 华东理工大学学报(自然科学版),2005,31:27-30.
[16]	Yin A Y,Guo X Y,Dai W L,et al.Effect of Initial Precipitation Temperature on the Structural Evolution and Catalytic Behavior of Cu/SiO2 Catalyst in the Hydrogenation of Dimethyloxalate[J]. Catal Commun,2011,12(6):412-416.

蒸氨压力对Cu/SiO₂催化剂的影响及其草酸二甲酯加氢性能

Influences of the Ammonia Evaporation Pressure on the Structure of Cu/SiO₂ Catalysts and Catalytic Performances for Dimethyl Oxalate Hydrogenation to Ethylene Glycol

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