油脂氢化三元金属催化剂制备及性能研究

在相同的加氢条件下,对自制Cu-Ni-Cr三元金属催化剂与Cu-Ni二元金属催化剂和进口单元镍催化剂的加氢性能进行了比较。结果表明,三元金属催化剂的活性高于二元金属催化剂,选择性高于单元金属催化剂。关于氢化油的固体脂肪指数,多元催化剂和单元催化剂的性能接近。     

草酸二甲酯加氢制乙二醇Cu/SiO_2催化剂失活研究

采用沉积-沉淀法制备Cu/SiO_2催化剂,研究Cu/SiO_2催化剂在草酸二甲酯制乙二醇反应中的活性及稳定性。采用XRD、TG、SEM和EDS等对催化剂进行表征,分析催化剂的失活原因。结果表明,催化剂表面积炭和活性组分铜的烧结是造成催化剂失活的主要原因。在高空速1.5 h~(-1)下,对催化剂进行寿命考察,结果表明,运行350 h,草酸二甲酯转化率维持95%以上,乙二醇选择性下降至约60%。     

模拟偶氮染料废水处理的共沉淀型催化剂研制

实验采用催化湿式氧化法对甲基橙模拟偶氮染料废水进行处理;催化剂的制备采用共沉淀方法,以 Cu、Fe 为催化剂活性组分,Ce 、La 为催化助剂,而制备多组分复合催化剂,研究了催化剂组分构成对催化剂性能的影响.实验中以催化剂的活性和稳定性综合对催化剂性能的评定,活性以水样的脱色率表示,而稳定性以原子吸收对组分的溶出浓度来表示.通过现代测试技术 FT-IR、XRD、原子吸收等的测定,对催化剂性能进行检测.实验结果表明,双组分催化剂 Cu1Fe1的性能优于单组分的 Cu 或 Fe 催化剂,而 Cu-Fe-Ce-La=1∶1∶1∶1的性能更优一步.     

锑钛复合催化剂应用研究

为了减少聚酯中重金属锑的含量，在降低三醋酸锑催化剂用量的基础上，添加少量的高活性的铁化合物作为助催化剂，组成锑钛复合艟化体系，在16m^3间歇聚酯装置上生产聚酯。与单一醋酸锑催化体系相比，锑钛复合健化体系中的锑含量大幅度下降，缩短聚合时间19．7％，在整个缩聚过程中锑钛复合催化体系表现出高的催化活性。两种催化体系生产的聚酯常规性能基本相当，分子量分布、热性能、流变性能等也基本相同，但锑钛复合催化体系生产的聚酯切片的色相略有下降。     

TiO2/海泡石负载型催化剂的制备及其光催化活性

采用混合焙烧方法,制得TiO2/海泡石负载型催化剂,研究了在该催化剂催化作用下,水溶液中邻苯二甲酸二乙酯（DEP）的光催化降解行为.结果表明：催化剂的用量和TiO2的负载量对光催化降解速率都有影响.对于负载型催化剂,TiO2的负载量对其催化活性及DEP的降解速率有较大影响.当使用A101/海泡石催化剂,用量为2 g/L和4 g/L时,TiO2负载量的较佳值均为5%.并对负载型催化剂的形貌及晶型进行了X射线衍射（XRD）和扫描电子显微镜（SEM）分析.     

二硝基甲苯液相加氢催化剂研究进展

甲苯二胺(TDA)作为甲苯二异氰酸酯(TDI)的合成中间体,广泛应用于聚氨酯工业中.本综述介绍了二硝基甲苯(DNT)液相加氢制TDA催化剂在国内外的研究进展,对各类催化剂催化DNT加氢性能进行了分析,指出了各类催化剂的优缺点,提出了DNT液相加氢催化剂由晶态向非晶态方向的发展趋势.     

辛醇液相加氢精制催化剂的研究

采用共沉淀法制备了一种新型辛醇液相加氢催化剂。试验研究了助剂铝和不同的载体加入方式对催化剂性能的影响。用压汞法和TPR分别对催化剂的孔结构和还原性能进行了考察，并采用小型加压评价装置对催化剂的加氢活性进行了评价。结果表明，在该催化剂上异辛醛的加氢率达90％，辛烯醇加氢率约80％，加氢产物中辛醇质量分数提高0.5个百分点；Ni/SiO₂系催化剂中加入铝助剂有利于提高加氢活性，加入质量分数以4.5％～6.5％为最佳；催化剂的还原温度应低于600 ℃。     

Ru/C催化剂在苯选择加氢反应中的催化性能

采用沉积沉淀法制备了以活性炭(C)为载体的Ru催化剂,研究了Ru/C催化剂在苯选择加氢反应中的催化性能,并对Ru/C催化剂进行了表征.结果表明:Ru在催化剂中的分散性好,Ru/C催化剂具有较高的催化活性;适宜的反应条件为温度140℃,压力5.0 MPa,催化剂中Ru质量分数为4.0％,苯的转化率达40％以上,产物环己烯...     

新型共聚物催化剂在醋酸异丙酯合成中的应用

采用新型磺化聚苯乙烯-co-甲基丙烯酸丁酯P（St-co-BMA）代替传统的浓硫酸催化异丙醇与冰乙酸的酯化反应。实验结果表明，P（St-co-BMA）对醋酸异丙酯的合成反应具有较好的催化活性。醋酸异丙酯的产率与新型催化剂的用量有关，当m(催化剂)∶m(异丙醇)=0.2∶1.0、酯化反应时间5 h时，醋酸异丙酯产率可达到74%以上。合成的共聚物催化剂经5次使用后,使醋酸异丙酯产率仍可达68%。该催化剂可用稀硫酸再生，多次使用过的催化剂经再生后的催化活性与新制备的共聚物催化剂的催化活性相比几乎没有差别。     

Epoxidation of Propylene with Hydrogen Peroxide Over TS-1 Catalyst Synthesized in the Presence of Polystyrene

Titanium silicalite-1 (TS-1) catalyst was synthesized in the presence of polystyrene (PS) particles (denoted as TS-1_PS catalyst) for use in the epoxidation of propylene with hydrogen peroxide. For the purpose of comparison, TS-1 catalyst was also synthesized by a conventional method (in the absence of polystyrene particles). In the epoxidation of propylene, the TS-1_PS catalyst showed a higher conversion of hydrogen peroxide and a higher selectivity for propylene oxide (PO) than the TS-1 catalyst. Consequently, the TS-1_PS catalyst showed a higher yield for PO than the TS-1 catalyst. Characterization results showed that the high catalytic performance of TS-1_PS was attributed to the enhanced hydrophobic property of the catalyst and the suppressed formation of anatase TiO₂ in the catalyst.     

新型CBS凝胶催化剂的合成及催化性能

1,1-二苯基-1-[(2S,4R)-4-(4-乙烯基-苄氧基)-2-吡咯烷基]-甲醇（功能单体4）、苯乙烯与聚醚Pluronic F-127在过氧化月桂酰引发下进行溶液聚合，得到独特的梳状接枝共聚物。接枝共聚物进一步反应，形成交联的CBS催化剂前体（G-CBSP）。前体与甲基硼酸在甲苯-四氢呋喃中进行缩合反应，得到新型CBS凝胶催化剂（G-CBS），用于催化苯乙酮的不对称还原反应。通过FTIR对催化剂结构进行表征，利用SEM观察反应介质中聚醚Pluronic F-127组分对催化剂凝胶形态的影响，考察G-CBS的催化效果及循环使用情况，比较了其与聚苯乙烯负载的CBS催化剂的催化性能。结果表明：聚醚Pluronic F-127片段的引入对G-CBS具有增溶效应，强化了催化剂与反应体系的相容性，有效解决了高交联度负载型催化剂选择性下降的问题。使用该催化剂还原产物苯乙醇ee值达94%，接近CBS均相催化反应的性能，优于目前报道的异相负载体系。催化剂循环使用5次，苯乙醇ee值仍可达到90%以上，苯乙酮转化率接近100%。     

Use of a nickel-boride–silica nanocomposite catalyst prepared by in-situ reduction for hydrogen production from hydrolysis of sodium borohydride

Hydrogen was produced by hydrolysis of sodium borohydride (NaBH₄) using nickel-boride–silica nanocomposite catalyst. The catalyst was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive X-ray spectrometry (EDX). The Ni-B–silica nanocomposite catalyst was found to consist of amorphous Ni-B nanoparticles attached to the surface of amine-modified silica nanosphere. The kinetics of hydrolysis of NaBH₄ by Ni-B–silica composite catalyst was investigated. The effects of temperature, NaBH₄ concentration, and catalyst concentration on hydrogen generation were also investigated. A rate of hydrogen generation as high as 1916 ml H₂/min/g Ni was achieved by catalytic hydrolysis of NaBH₄. The stability of the composite catalyst was also explored.     

利用纳米SO42-/SnO2催化合成草酸二异戊酯

采用沉淀-浸渍法合成了新型催化材料纳米SO42-/SnO2,并利用SO42-/SnO2为催化剂,催化合成草酸二异戊酯,考察了催化剂焙烧温度、反应物配比、反应时间、催化剂质量、带水剂用量对草酸二异戊酯收率的影响,同时也考察了催化剂的重复使用性能。实验结果表明:SO42-/SnO2在由草酸和异戊醇反应生成草酸二异戊酯过程中,具有良好的催化活性,在最佳条件下,草酸二异戊酯收率达到了95.4%。     

Effect of Al<Subscript>2</Subscript>O<Subscript>3</Subscript>-ZrO<Subscript>2</Subscript> xerogel support on hydrogen production by steam reforming of LNG over Ni/Al<Subscript>2</Subscript>O<Subscript>3</Subscript>-ZrO<Subscript>2</Subscript> catalyst

An Al₂O₃-ZrO₂ xerogel (AZ-SG) was prepared by a sol-gel method for use as a support for a nickel catalyst. The Ni/AZ-SG catalyst was then prepared by an impregnation method, and was applied to hydrogen production by steam reforming of LNG. A nickel catalyst supported on commercial alumina (A-C) was also prepared (Ni/A-C) for comparison. The hydroxyl-rich surface of the AZ-SG support increased the dispersion of nickel species on the support during the calcination step. The formation of a surface nickel aluminate-like phase in the Ni/AZ-SG catalyst greatly enhanced the reducibility of the Ni/AZ-SG catalyst. The ZrO₂ in the AZ-SG support increased the adsorption of steam onto the support and the subsequent spillover of steam from the support to the active nickel sites in the Ni/AZ-SG catalyst. Both the high surface area and the well-developed mesoporosity of the Ni/AZ-SG catalyst improved the gasification of adsorbed surface hydrocarbons in the reaction. In the steam reforming of LNG, the Ni/AZ-SG catalyst showed a better catalytic performance than the Ni/A-C catalyst. Moreover, the Ni/AZ-SG catalyst showed strong resistance toward catalyst deactivation.     

Hydrogenation of cottonseed oil with reused catalyst

Cottonseed oil was hydrogenated using both new (Rufert catalyst flakes) and reused (up to five uses) catalysts at 130–169C, at a pressure of 45 psig, and with high degrees of agitation. The activity of the catalyst increased initially with use, especially at 130C, but with continued use the activity decreased. The selectivity of the hydrogenation decreased with reuse of the catalyst, especially at lower temp. Isomerization decreased slightly as the catalyst was used only at higher temps. The induction period found with fresh catalyst at 130C was eliminated in runs with second- and third-use catalyst. A small induction period was noted with fifth-use catalyst. Treatment of once-use catalyst with air severely reduced the catalyst activity. Steam- and vacuum-treatment of the catalyst resulted in a slightly less active catalyst than a hydrogen-treated catalyst. None of these treatments significantly affected selectivity or isomerization. Results of this investigation can be explained in large part by the concn of hydrogen absorbed on the catalyst surface.     

Simulation of the catalyst layer in PEMFC based on a novel two-phase lattice model

A lattice model of catalyst layer in proton exchange membrane fuel cells (PEMFCs), consisting of randomly distributed catalyst phase (C phase) and mixed ionomer-pore phase (IP phase), was established by means of Monte Carlo method. Transport and electrochemical reactions in the model catalyst layer were calculated. The newly proposed C-IP model was compared with previously established pore-solid two phase model. The variation of oxygen level and reaction rate along the thickness of catalyst layer with cell current was discussed. The effect of ionomer distribution across catalyst layer was studied by comparing profiles of oxygen level, reaction rate and overpotential, as well as corresponding polarization curves.     

功能化硅胶负载醋酸锌催化合成月桂酸甲酯的研究

以正硅酸四乙酯(TEOS)为硅胶(SG)的来源,将硅胶用丁二酸(SA)功能化之后,采用溶胶-凝胶法负载活性组分醋酸锌(ZnA),制备功能化硅胶负载醋酸锌催化剂(SG-SAZnA);并用红外光谱(IR)及X射线衍射法(XRD)对该催化剂进行了表征;通过用该催化剂催化合成月桂酸甲酯的实验,考察了反应时间、反应温度、醇酸摩尔比、催化剂用量对反应酯化率的影响,探讨了该催化剂的催化性能.结果表明,在醇酸摩尔比为7:1,催化剂用量为酸质量的5%,75℃下反应1.5 h,酯化率最高达75%;催化剂重复使用5次后,月桂酸的酯化率仍可达73.8%.     

SO_4~(2-)/TiO_2 催化合成甲基丙烯酸甲氧基乙酯

沉淀-浸渍法制备了固体超强酸SO_4~(2-)/TiO_2催化剂,利用该催化剂合成了甲基丙烯酸甲氧基乙酯。考察了浸渍酸Hp_2SO_4浓度和焙烧温度对催化剂活性的影响,X射线衍射(XRD)分析确定催化剂为锐钛矿晶型结构。采用电子自旋共振(ESR)对催化剂进行了分析与表征,ESR波谱能够检测出催化剂空位或缺陷数量即催化剂活性的强弱,结合相关催化反应的转化率,最终确定了浸渍酸的较佳浓度为0.75 mol/L,最佳焙烧温度为450℃。研究了催化剂的重复使用性能,发现催化剂循环使用2次后活性下降明显,ESR初步分析表明其主要原因是由于催化剂表面积碳和吸附了有机物而导致的。     

柱状阳离子交换树脂上乙基叔丁基醚的合成

将国产粒状强酸性阳离子交换树脂S - 5 4制成柱状催化剂 ,在其作用下 ,以乙醇和叔丁醇为原料 ,于常压液相条件下合成乙基叔丁基醚 (ETBE) .考察了温度、催化剂用量、反应物初始摩尔比以及水的存在等因素对反应速度的影响 ,建立了一个 7参数动力学模型 ,模型与实验数据吻合较好 .并将柱状和粒状S - 5 4树脂对该反应体系的催化效果进行了比较     

NiO/MgO/Al2O3固体碱负载磺化酞菁钴催化剂的制备及表征

采用浸渍法制备了NiO/MgO/Al2O3负载磺化酞菁钴(CoPcS)催化剂,研究了其催化硫醇常温氧化反应性能,并用X射线衍射、BET法和CO2-程序升温脱附等技术进行表征.与MgO/Al2O3-CoPcS催化剂相比,NiO/MgO/Al2O3-CoPcS催化剂具有较高的初活性和良好的稳定性.