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Key Laboratory for Green Chemical Technology of the Ministry of Education

Key Laboratory for Green Chemical Technology of the Ministry of Education. 文献报告 2012.12.30. 胡宗元. Background. 各种合成方法的比较. 1 、环氧乙烷 (EO) 水合法: EG 的选择性和产率低,以石油为原料生产的 , 目前石油价格上涨 , 面临产量不足的问题 , 经济性会降低。.

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Key Laboratory for Green Chemical Technology of the Ministry of Education

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  1. Key Laboratory for Green Chemical Technology of the Ministry of Education 文献报告 2012.12.30 胡宗元

  2. Background

  3. 各种合成方法的比较 1、环氧乙烷(EO)水合法:EG的选择性和产率低,以石油为原料生产的,目前石油价格上涨,面临产量不足的问题,经济性会降低。 2、由合成气合成乙二醇:天然气、石油残渣和煤是合成气的原料,资源丰富,价格便宜。由合成气经草酸酷合成乙二醇反应条件温和,不需高压,如果能进一步改进催化剂,提高选择性,进行工业放大, 是近年来被公认为技术性和经济性较好的一种工艺路线。

  4. 草酸酯催化加氢的研究制乙二醇的原理 This indirect synthesis process includes two steps: the coupling of CO with nitrite esters to oxalates, and the hydrogenation of oxalates to EG 1: CO偶联反应:2CO+2RONO→2NO+(COOR)2 再生反应: 2ROH+1/2O2+2NO→2RONO+H2O 总反应为:2CO+2ROH+1/2O2→(COOR)2+H2O R=CH3 or C2H5 草酸酯一个酯基发生加氢反应生成乙醇酸酯,之后另一个酯基继续加氢生成EG 2: (COOR)2+2H2 →ROOCCH2OH+ROH ROOCCH2OH+2H2 →HOCH2CH2OH+ROH 总反应为: (COOR)2+4H2 →HOCH2CH2OH+2ROH R=CH3 or C2H5 EG还可与H2继续发生反应,分解成乙醇和水: HOCH2CH2OH+H2 →CH3CH2OH+H2O

  5. 草酸酯加氢催化剂的研究进展 草酸酯催化加氢生产EG的工艺可分为以Ru等贵金属催化剂为主的液相均相加氢法和以Cu催化剂为主的非均相气相加氢法。 1:液相均相加氢催化剂的研究: Matteoli et al. have investigated the homogeneous hydrogenation of oxalates, and obtained an EG yield of 82% under H2 pressure of 20 MPa at 453K using Ru(CO)2(Ac)2(PBu)3 as the catalyst. Recently, Teunissen and coworkers applied Ru-based homogeneous catalysts in the hydrogenation of dimethyl oxalate (DMO); an EG yield of 95% was obtained under milder conditions (7 MPa, 373 K).

  6. 2:非均相气相加氢催化剂的研究 Cu-based heterogeneous catalysts homogeneous catalysts are expensive and suffer from separation issue Cu-based catalysts supported on different carriers (SiO2,Al2O3, ZnO, and La2O3)were studied, among which the Cu/SiO2 catalyst afforded the highest yield of EG in the hydrogenation of DMO and DEO due to the weak acidic and basic properties of SiO2. Recently, mesoporous materials such as hexagonal mesoporous silica (HMS) and SBA have been used as supports for the reaction.

  7. 草酸酯催化加氢制乙二醇 ammonia evaporation (AE), ion exchange, sol–gel, deposition precipitation, and impregnation have been used to fabricate silica-supported copper catalysts. 1:Catalyst preparation

  8. AE法制的催化剂透射电镜(TEM)图 焙烧后的Cu/SiO2催化剂 还原后的Cu/SiO2催化剂 the AE method could effectively disperse copper species on the supports

  9. 2:mesoporous materials as support mesoporous materials suchas HMS, SBA-15, FSM-16, M41S It is well known that mesoporous materials which possess high surface area, large pore volume, regular structure, uniform pore size distribution, and relative high thermal stability.

  10. TEM image of 5-Cu-com-SiO2 TEM image of 50% Cu/SBA-15 TEM images for 5-Cu-HMS

  11. Compared with the silica-supported one, the copper-containing HMS sample exhibits much better DMO conversion and EG selectivity under the same reaction conditions, which may be attributed to the higher copper surface area and stronger copper–silica interaction.

  12. 3:the effect of promoter such as boric oxide Stable and efficient B–Cu–SiO2 catalysts for the hydrogenation of dimethyl oxalate (DMO) to ethylene glycol were prepared through urea-assisted gelation followed by impregnation with boric acid.

  13. a • b TEM images of catalysts reduced by 5% H2-95% Ar at 623 K: (a) Cu-SiO2; (b) 1B-Cu-SiO2 a suitable amount of boric oxide doping tended to improve copper dispersion and retard the growth of copper particles

  14. Catalytic stability was greatly enhanced in the B–Cu–SiO2 catalyst, because of the formation and preservation of appropriate distributions of Cu+ and Cu0 species on the catalyst surfaces. The effect of boric oxide was attributed to its relatively high affinity for electrons, which tended to lower the reducibility of the Cu+ species. ???

  15. 草酸酯催化加氢制乙醇酸酯 草酸酯制催化加氢第一步是生成乙醇酸酯,草酸二甲酯(DMO)生成乙醇酸甲酯(MG),草酸二乙酯生成乙醇酸乙酯(MPEG)。乙醇酸酯是一种非常重要的有机化工中间体,广泛用于化工、医药、农药、饲、香料和染料等诸多领域。 草酸二甲酯(DMO)选择性加氢得到MG,经济性及其绿色化都要远远优于其它制备方法。

  16. Synthesis of MG by hydrogenation of Dimethyl Oxalate over Cu-Ag/SiO2 Catalyst reaction temperature at 473.2K, 40-60 mesh catalyst diameter, H2/DMO ratio 40, and 1.0 h-1of LHSV the conversion of DMO is 90.6% ,and the selectivity of MG can reached 89%

  17. Ag/SiO2 catalyst for the regioselective synthesis of methyl glycolate and ethylene glycol Reaction conditions: catalyst (2 g), 493 K for A and 553 K for B, 2.5 MPa, LHSV =0.2h-1,and H2/DMO=100 (mol mol-1). A:Conversion of DMO and MG selectivity vs. time on stream B: Conversion of DMO and EG selectivity vs. time on stream

  18. Ag/MCM-41 catalyst for the chemoselective synthesis of methyl glycolate and ethylene glycol The highest selectivity to MG and EG could be up to 95% and 99% at 493K and 553K respectively.

  19. 草酸酯催化加氢制乙醇 由前面可知,草酸酯催化加氢生成乙二醇,在H2环境及催化剂作用下,EG还可以与H2反应分解成乙醇和水。 乙醇是重要的大宗化工产品 广泛用于医药、食品、燃料、化工等行业,也是石油的潜在替代燃料。 目前一些乙醇制备工艺为乙酸加氢制乙醇工艺、淀粉发酵制乙醇工艺、纤维素乙醇工艺等,也可以通过合成气催化制乙醇。

  20. Synthesis of Ethanol via Syngas on Cu/SiO2 catalysts A:DMO conversion and product selectivities as functions of reaction temperature (453− 573 K). B:DMO conversion and EtOH selectivity vs time on stream at 553 K.

  21. 关注的一些问题 1:DMO或DEO催化加氢中活性中心是Cu0,Cu+,还是Cu0和Cu+的协同作用,关于反应机理的探讨 2:催化剂的选择性合成反应,如改变温度、压力等工艺条件控制反应的选择性 3:介孔分子筛如HMS,SBA-15,MCM-41的应用

  22. References Ethylene glycol properties, synthesis, and applications Highly active and selective copper-containing HMS catalyst in the hydrogenation of DMO to EG One Pot Synthesis of Ultra-High Copper Contented CuSBA-15 material Effect of boric oxide doping on the stability and activity of a Cu-SiO2 catalyst for hydrogenation of DMO to EG High activity and selectivity of AgSiO2 catalyst for hydrogenation of DMO Synthesis of Methyl Glycolate by Hydrogenation of Dimethyl Oxalate over Cu-AgSiO2 Catalyst AgMCM-41 as a highly efficient mesostructured catalyst for the chemoselective synthesis of methyl glycolate and ethylene glycol Synthesis of Ethanol via Syngas on CuSiO2 with balanced Cu-Cu+ sites

  23. Thankyou

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