Resin-Based Catalysts for the Hydrogenolysis of Glycerol to Propylene Glycol

Three alkysulfonic resins were obtained by co-polymerization of 2-acrylamido-2-methyl-propansulfonic acid with N,N-dimethylacrylamide and ethylene dimethacrylate (the cross-linker), with respectively 4, 20 and 40 mol% cross-linking degree (DAE26-4, DAE26-20, DAE26-40). These resins were employed as acidic components in physical mixtures with Ru/C (5 %, w/w) or as supports for bifunctional ruthenium and copper catalysts, to be used in the hydrogenolysis of glycerol (20 %, w/w, in water). The physical mixtures were more efficient than the bifunctional catalysts, but temperatures as high as 200 °C are required to obtain an appreciable activity. However, in view of their relatively high thermal stability in comparison with the sulfonated polystyrene-divinylbenzene ion-exchange catalysts employed so far they can withstand this temperature, while Amberlyst 70 cannot be employed above 180–190 °C. Interestingly, the catalytic systems based on physical mixtures of DAE with Ru/C resins at 200 °C are much more selective towards propylene glycol than those containing A70 are at 180 °C.     

Ni-Cu双金属催化剂上甘油催化转移氢解制备1,2-丙二醇

采用等体积浸渍法制备了一系列Ni-Cu/γ-Al2O3双金属催化剂.考察了Ni/Cu质量比、金属负载量和不同供氢体等因素对甘油催化转移氢解制备丙二醇反应的影响.结果表明:当Ni/Cu质量比为3∶2时,催化剂表现出最好的催化活性.当催化剂Ni-Cu总负载量为25％(15Ni-10Cu/γ-Al2O3)时,在甲酸和甲醇两种供氢体条件下均具有最佳催化效果,尤其以甲酸为供氢体时效果更好,在220℃下反应16h,甘油转化率达85.2％,1,2-丙二醇的选择性为80.4％.     

甘油氢解合成1,2-丙二醇铜锌铝催化剂的性能

采用共沉淀法制备了铜锌铝类水滑石前驱体,经焙烧和还原后制得铜基催化剂。采用XRD、H₂-TPR、H₂-TPD、NH₃-TPD和CO₂-TPD等表征手段并结合甘油氢解反应评价,研究了类水滑石前驱体的老化对催化剂结构和性能的影响,考察了反应条件对催化剂甘油氢解反应性能的影响。结果表明,老化有利于形成结构更为完整的类水滑石前驱体,但对铜物种的还原性能未造成显著影响。与由未老化前驱体制备的催化剂相比,由老化前驱体制备的铜锌铝催化剂具有较大Cu表面及较大酸量,但表面碱中心数量较低,从而该催化剂具有较好的甘油氢解活性及稳定性。在220 ℃、H₂压力3.0 MPa、n(H₂)/n(甘油)为18.9、甘油重时空速1.26 h^-1及质量分数为60%甘油水溶液的条件下,经老化前驱体制备的铜锌铝催化剂上甘油转化率接近100%、1, 2-丙二醇选择性约为96%。     

Hydrogenolysis of Glycerol to Propanediol Over Ru: Polyoxometalate Bifunctional Catalyst

Ruthenium-doped (5 wt%) acidic heteropoly salt Cs_2.5H_0.5[PW₁₂O₄₀] (CsPW) is an active bifunctional catalyst for the one-pot hydrogenolysis of glycerol to 1,2-propanediol (1,2-PDO) in liquid phase, providing 96% selectivity to 1,2-PDO at 21% glycerol conversion at 150 °C and an unprecedented low hydrogen pressure of 5 bar. Rhodium catalyst, 5%Rh/CsPW, although less active, shows considerable selectivity to 1,3-PDO (7.1%), with 1,2-PDO being the main product (65%).     

丙二醇对乳胶涂料性能的影响

研究了聚醋酸乙烯酯水性乳胶涂料中助溶剂丙二醇的加入量对涂料性能的影响,在其他助剂、颜填料和主要成膜物质加入量都不变的情况下,分析了丙二醇不同加入量对涂料粘度、表面干燥时间、对比率、耐洗刷性的影响规律,从而确定最佳的加入量。研究结果表明:随着丙二醇质量的增加,体系粘度会下降,表面干燥时间会缩短,涂膜的对比率呈现不规律变化,涂膜的耐洗刷性次数会下降。     

Ni/NaX: A Bifunctional Efficient Catalyst for Selective Hydrogenolysis of Glycerol

Non-noble metal Ni/NaX catalyst was prepared and used in the hydrogenolysis of aqueous glycerol. Characterization by XRD, SAED, H₂ chemisorption, ICP and NH₃-TPD techniques disclosed that the proper strong acid sites were responsible for the high activity and selectivity. Over Ni/NaX catalyst, conversion of glycerol reached 86.6% with 94.6% selectivity to glycols including 1,2-proplyene glycol and ethylene glycol under 6.0 MPa H₂ pressure at 200 °C after 10 h reaction. Additionally, the effects of time, temperature, and H₂ pressure were investigated in detail.     

Influence of Parameters on Glycerol Hydrogenolysis over a Cu/Al2O3 Catalyst

The influence of technological parameters like hydrogen pressure, temperature, glycerol concentration in aqueous solution, amount of catalyst, stirring speed, and reaction time on glycerol hydrogenolysis to 1,2‐propanediol over a Cu/Al₂O₃ catalyst prepared by coprecipitation was investigated. Functions describing the process were glycerol conversion as well as selectivity to 1,2‐propanediol and to by‐products in the liquid and gas phase. The structure and properties of synthesized Cu/Al₂O₃ were characterized by X‐ray diffraction, energy dispersive X‐ray microanalysis, BET surface area, average pore volume, and pore diameter. Catalyst recycle studies were also performed.     

尿素制镁铝水滑石催化剂催化合成丙二醇单甲醚

研究了甲醇与环氧丙烷在固体碱催化荆尿素制水滑石存在下非均相合成丙二醇单甲醚。考察了反应温度、压力、反应时间、原料摩尔比、催化剂用量等因素对环氧丙烷转化率和丙二醇单甲醚选择性的影响,在反应温度140℃、醇烷比4：1、催化剂用量（w／w）0．9％、反应时间6h条件下,环氧丙烷转化率为95％左右,丙二醇单甲醚选择性达97％以上,丙二醇单甲醚收率达92．2％。该固体碱催化剂使用后无需任何处理。可重复使用,是一种稳定性好,选择性高的环境友好催化剂。     

甲基磺酸钙催化合成香草醛缩丙二醇的研究

以草香醛和1,2-丙二醇为原料,甲基磺酸钙为催化剂,合成了香草醛缩丙二醇。考察了影响收率的因素。其最优条件为：香草醛：1,2-丙二醇：催化剂：带水剂为0．15mol：0．225mol：1．00g：15mL,反应在回流温度下进行,反应时间3．0h。收率可达87．5％。     

固体强碱绿色催化环氧丙烷水解合成1,2-丙二醇

该文制备了不同碱强度的固体碱催化剂,并应用于环氧丙烷(PO)水解合成1,2-丙二醇的反应。结果表明:随着催化剂碱强度的增加,环氧丙烷的转化率不断升高;说明强碱催化剂有利于环氧丙烷水解反应。在此基础上,作者系统考察了催化剂用量、反应温度、原料摩尔比和反应时间对催化性能的影响。结果表明:当催化剂CaO-ZrO2质量为反应原料质量的1.0%,反应温度为120℃,反应原料配比为:n(H2O)∶n(PO)=5∶1,反应时间2h时,其催化效果较优,环氧丙烷转化率最高为92.3%,1,2-丙二醇选择性可达89.4%。     

甘油氢解制二元醇的研究进展

近年来,随着国内外生物柴油产业的快速发展,生成大量副产物甘油,合理利用过剩的甘油将有助于整个生物柴油产业的经济效益。本文针对以甘油为底物,催化氢解合成高附加值二元醇的研究进行了综述,介绍了甘油催化氢解成二元醇的反应机理和研究现状,并对发展前景作了展望。     

甲醇制丙烯催化剂对产物选择性的研究

通过考察甲醇制丙烯催化剂的前期、中期、后期产物组分,结果表明:催化剂后期对丙烯的选择性低于前期、中期;而催化剂前期对丙烷、氢气选择性远远高于中、后期。     

合成丙二醇甲醚丙酸酯用固体超强酸催化剂的研究

研究了合成丙二醇甲醚丙酸酯（PMP）用固体超强酸催化剂SO4^2-／TiO2的制备工艺,得到了催化剂制备的适宜工艺。并对制得催化剂进行了催化性能测试,结果表明PMP酯化产率可达75％。催化剂经X荧光光谱分析和X射线衍射物相分析表明,其主要结构单元为SO3和TiO2,催化剂晶相为锐钛型。制备所得催化剂贮存1个月后发现其催化活性下降约10％。     

强酸性阳离子交换树脂催化合成丙二醇二苯甲酸酯的研究

以苯甲酸、1,2-丙二醇为原料。直接酯化合成丙二醇二苯甲酸酯,分别研究了反应温度、反应时间、原料配比、带水剂、催化剂用量等条件对合成反应的影响,确定了最佳工艺条件。该方法合成丙二醇二苯甲酸酯的最佳工艺条件是：反应温度110℃;反应时间240min;n(苯甲酸)：n(1,2-丙二醇)为2．1：1;催化剂用量为总物料质量的3％：带水剂苯为15mL/（1．2-丙二醇为0．2mol的情况下)。丙二醇二苯甲酸酯的收率达到95．94％。催化剂不经处理可循环使用多次。该催化剂具有价廉易得、催化活性好、不腐蚀设备、无环境污染等优点。     

Direct Hydrogenolysis of Highly Concentrated Glycerol Solutions Over Supported Ru,Pd and Pt Catalyst Systems

Abstract  

The evaluation of supported precious metal catalysts, in combination with and without solid acids, for the hydrogenolysis of highly concentrated glycerol solutions, with the aim to produce lower alcohols, in particular 1-propanol was studied. GCMS analysis of the product mixtures obtained has shed some light on the possible mechanism leading to unwanted condensation products, as well as the composition of these compounds.     

甲醇制丙烯催化剂国产化研究进展

文章对甲醇制丙烯(MTP)催化剂国产化的重要性与发展现状做了概述,同时介绍了神华宁夏煤业集团研发中心联合国内多家科研实力较强的单位进行甲醇制丙烯催化剂研究,最终实现MTP催化剂国产化的历程。     

Deactivation of CuZn Catalysts Used in Glycerol Hydrogenolysis to Obtain 1,2-Propanediol

Different CuZn catalysts were prepared by coprecipitation method with Cu/Zn atomic ratio of 0.2, 0.4, 1.0, 2.5 and 6.0. Monometallic Zn and Cu catalysts and a bimetallic catalyst (Cu/Zn?=?2.5) prepared by physical mixture of the precursors were also studied. These catalysts were tested in the glycerol hydrogenolysis reaction and the higher yields to 1,2-propanediol were achieved for Cu/Zn atomic ratio?≥?1 samples. The deactivation of a representative catalyst (Cu/Zn?=?1) was evaluated and its yield to 1,2 propanediol decreases until ca 40% after five runs. To explain this behavior, fresh and used catalysts were characterized by different techniques. Chemical analysis of solid catalysts and liquid reaction medium confirmed the leaching of Zn species under our reaction conditions. This process promotes Cu sintering which is proposed as the actual reason of the observed deactivation in the glycerol hydrogenolysis for this catalytic system.     

Highly Diluted Copper in a Silica Matrix as Active Catalyst for Propylene Oxidation to Acrolein

The use of copper phthalocyanine as the copper precursor extremely diluted in a silica matrix (below 0.1%) was found to result in a very active catalyst in the selective oxidation of propene by oxygen to produce acrolein with selectivities above 50% and yields of ~10%.