Ni-Mo/Al2O3加氢脱氧催化剂的研究

在连续流动固定床微型反应器内,反应温度240～320℃,氢油比700,液体空速1.5 h-1,压力4.0MPa的条件下,详细考察了Mo-Ni/Al2O3系列催化剂对模型含氧化合物醇和酸的加氢脱氧反应性能.结果表明Mo-Ni/Al2O3催化剂对醇和酸具有高的加氢脱氧活性.其中Mo16Ni6/Al2O3催化剂在280℃时,乙醇、乙酸和丙酸加氢脱氧转化率分别为94.3%、94.9%和98.8%.钼助剂的加入显著地提高Ni基催化剂的加氢脱氧活性,大大地降低了氧化态Ni的还原温度,因为钼助剂的加入抑制了NiO与Al2O3强的相互作用,结果显著地降低了氧化态催化剂中的NiAl2O4相的量,增加了的NiO的量.     

硫化温度对CoMo/Al2O3加氢处理催化剂的影响

本文就CoMoAl2O3加氢处理催化剂、硫化过程相关影响因素、脱硫活性因素等的关系展开研究,通过对TEM方法、XPS方法等就催化剂状况展开表征.通过结果得知,硫化温度的提升,会提高催化剂的硫化度状况及载硫量.伴随着硫化温度的改变,催化剂的活性逐渐发生改变,逐渐向高活性Co-Mo-S转变.当硫化温度处于410℃时,催化剂...     

Zr改性对NiW/Al2O3催化剂加氢性能的影响

引言随着原油重质化趋势的不断加剧和环保法规对轻质油品质量要求的不断提高,劣质重油轻质化及清洁化生产成为石油加工技术发展的主要方向。溶剂脱沥青是重油脱碳改质工艺之一,得到的脱沥青油一般作为催化裂化的掺炼原料,脱沥青油中较高的硫氮含量及稠环芳烃含量容易造成催化裂化催化     

制备条件对低Ni／Al2O3催化活性的影响

用含Ｐ、Ｍｏ的改性剂处理工业γ－Ａｌ２Ｏ３载体,制备了一种性能很好的低Ｎｉ／Ａｌ２Ｏ３催化剂,并考察了制备条件对其催化活性的影响,得到最佳的制备条件。     

制备方法对钯碳催化剂表面性质及其加氢性能影响

钯碳催化剂是一种常用的加氢催化剂，广泛应用于羰基加氢、烯烃加氢、硝基和亚硝基加氢等领域。Pd／C催化剂的制备大多采用浸渍法，一般包括载体预处理，活性金属浸渍、干燥、还原等步骤，还原过程大多采用H2还原。     

磷、柠檬酸改性对MoW/Ni/Al2O3催化剂性质及加氢脱氮性能的影响

采用等体积浸渍法制备了以γ-Al₂O₃为载体,Ni、Mo、W为活性金属组分的三金属催化剂,考察了磷改性、柠檬酸改性以及磷-柠檬酸组合改性对催化剂性质、加氢脱氮性能和脱氮选择性的影响。通过NH₃-TPD、Py-IR、H₂-TPR、XPS和HRTEM对催化剂进行表征,结果表明：磷改性不但提高了催化剂的表面弱酸量,而且提高了金属的硫化性能,促进碱性氮和非碱性氮的脱除,但磷改性导致金属活性相的堆垛层数偏高、分散度下降;柠檬酸改性降低了催化剂活性金属氧化物的硫化温度,提高了催化剂的加氢活性,但对氢解性能基本没有影响,表现为非碱性氮脱除性能的提高;而磷-柠檬酸组合改性,不但提高了催化剂的氢解性能,而且改善了其加氢活性,使催化剂对焦化蜡油中碱性氮和非碱性氮的脱除率均得到大幅提升,分别达到80.1%、54.9%。     

磷对MoNi/γ-Al2O3加氢处理催化剂性能的影响

采用分步浸渍法制备了不同磷含量的MoNiP/γ- Al2O3加氢预处理催化剂.采用TPR、HRTEM和XPS技术对催化剂进行表征,以噻吩和喹啉为模型化合物,考察催化剂的加氢脱硫和加氢脱氮活性.结果表明,磷与活性组分相互作用形成新Mo - Ni -O-P相,增加了低温还原峰面积,使还原峰峰顶温度升高.磷的引入提高了活性金属组分的硫化度,使催化剂的MoS2片晶层数更多,片层长度更长,有助于噻吩和喹啉克服空间位阻吸附在活性中心位上;但过量磷会使MoS2发生团聚,降低活性中心位数目,不利于提高催化剂活性.添加适量磷对催化剂表面和活性相进行有限度的改变,使催化剂具有最佳的脱硫和脱氮活性.     

Mo—Ni／Al2O3催化剂的TPR特性与加氢脱硫性能

应用ＴＲＰ、ＸＰＳ及ＸＲＤ等技术研究了用浸渍法制备了的Ｎｉ／Ａｌ２Ｏ３、Ｍｏ／Ａｌ２Ｏ３和Ｍｏ－Ｎｉ／Ａｌ２Ｏ３３种催化剂的还原性能,并将Ｍｏ－Ｎｉ／Ａｌ２Ｏ３双金属催化剂与同类型的Ｍｏ－Ｃｏ／Ａｌ２Ｏ３和Ｗ－Ｎｉ／Ａｌ２Ｏ３催化剂进行了比较。结果表明：在Ｍｏ－Ｎｉ－Ａｌ２Ｏ３中,ＭｏＯ３呈高度分散状态,ＮｉＯ的加入减弱了Ｍｏ与载体间的强相互作用,并在催化剂表面形成了两种易还原的复合物,大大降低了     

均一介孔Al2O3劣质蜡油加氢脱氮催化剂研究进展

提高加氢脱氮（HDN）性能是劣质蜡油加氢处理催化剂开发的关键和难点,而催化剂载体材料的制备及改性技术研究是获得高性能劣质蜡油加氢处理催化剂的核心。本文针对常规Al₂O₃孔径分布较大而不利于反应物的扩散及比表面积的提高问题,介绍了均一介孔Al₂O₃（MA）载体的制备方法（溶胶-凝胶法、沉淀法、水热合成法）及优缺点。为提高催化剂加氢脱氮活性,综述了Al₂O₃载体的助剂（磷、硼、氟）改性、复合氧化物（钛铝、硅铝复合氧化物）改性及复合改性的最新研究进展,分析了改性后载体酸性及与活性相间相互作用的变化以及对催化剂加氢脱氮性能的影响。指出未来应着重于均一介孔Al₂O₃载体及复合改性两方面的研究,以期获得高活性劣质蜡油加氢脱氮催化剂。     

Effect of preparation variables on the activity of Ni-W/Al2O3 hydrotreating catalysts

Studies have been carried out on the influence of preparation parameters on the activity of nickel-tungsten (Ni-W) catalysts, used to promote the hydrotreatment of model compounds representative of nitrogen, sulphur, oxygen and aromatic containing compounds which typically occur in coal derived liquids. The preparation variables considered for optimisation were the pH of the impregnating solution, the impregnation order, the starting Ni salts, the Ni/Ni + W ratio, the drying conditions and the calcination temperature. It was found that changes in pH, within the range where binding of the starting ions to alumina takes place, is not a significant variable influencing the activity. The use of nickel nitrate as a precursor yields better catalysts. If W is impregnated first it is redistributed during subsequent nickel impregnation, and better catalysts are obtained when Ni is impregnated first. The optimum Ni/Ni + W ratio is between 0.3 and 0.4, based on the total active metals present on the catalyst. The hydrodesulphurisation hydrodeoxygenation and hydrogenation activities decrease with increase in the drying temperature; the reverse is true for hydrodenitrogenation. An optimum activity is obtained when drying at 100°C in a closed oven. The optimum calcination temperature was found to be 500°C.     

共沉淀法制备Ni/Al2O3催化剂的研究

油脂加氢催化剂是以金属镍为活性组分、氧化铝为载体制备的Ni/Al2O3催化剂。在制备催化剂过程中,其合成条件直接影响着催化剂的最终活性。以工业硝酸镍、碳酸钠和自制氧化铝粉为原料,利用共沉淀的方法制备加氢催化剂,考察了反应温度、反应时间、反应液pH及反应过程中搅拌转速对催化剂活性的影响。通过实验数据汇总分析,最终确定制备Ni/Al2O3油脂加氢催化剂的最佳条件：反应温度为85 ℃、反应结束时溶液pH=8.0、反应时间为1.5 h、搅拌转速为600 r/min。在此条件下制备的Ni/Al2O3催化剂,经棕榈油加氢评价后测定的碘值最低。     

基于镁铝水滑石的Mo/Al2O3-MgO催化剂制备及其加氢脱硫性能

生产低硫或无硫柴油是当今世界范围内清洁燃料发展的趋势,加氢脱硫（HDS）是大规模生产清洁柴油最为有效的技术之一,而研制高活性的HDS催化剂成为该技术的关键。以镁铝水滑石与氧化铝的复合氧化物为载体,通过等体积浸渍法制备了一系列Mo/Al₂O₃-MgO催化剂,以二苯并噻吩（DBT）的正庚烷溶液为原料,在固定床反应器上评价所得催化剂的HDS活性,考察了不同镁铝比的水滑石、焙烧温度和添加量对催化剂物化性质和催化性能的影响。研究结果表明,镁铝比、焙烧温度和添加量均影响催化剂的酸性、金属还原性、硫化性能和MoS₂片晶的堆垛度等,当镁铝摩尔比为3、焙烧温度为800℃、成型时水滑石加入量为10%（质量分数）时,所制备催化剂的HDS活性最高,其脱硫率可达96.2%。这是由于该催化剂的酸性较适宜,活性组分与载体间的相互作用力适中,活性组分更易硫化,有助于提高MoS₂片晶的堆垛度进而改善催化剂的HDS性能。     

镍/氧化铝加氢催化剂的制备及性能研究

羟基新戊醛（HPA）的加氢多采用贵金属和铜系催化剂,为了更好地降低催化剂生产成本和操作成本,分别对比了共沉淀法和浸渍法制备的镍/氧化铝催化剂,并以HPA为原料,在固定床装置上考察了系列催化剂加氢合成新戊二醇（NPG）的催化性能。采用X射线衍射（XRD）、氮气物理吸附（BET）、一氧化碳脉冲吸附等方法进行表征,结果表明,浸渍法制备的20%镍/氧化铝催化剂,比表面积较大,金属分散性好,且催化剂中的镍物种易被还原,其反应性能良好。在相对较温和的反应条件下,即反应温度为103 ℃、反应压力为3 MPa、液时空速为1 h^-1、氢醛物质的量比为10时,HPA转化率为100%,NPG选择性为99.3%。在1 000 h的长周期评价过程中,该催化剂保持了较好的活性,具有更好的工业化前景。     

微波水热法制备含磷W/Al2O3催化剂及其加氢脱氮性能

采用微波水热法(MWH)制备含磷W/Al₂O₃加氢精制催化剂, 分别以磷酸(PA)、磷酸三乙酯(TEP)和羟基乙叉二磷酸(HEDP)为磷源, 考察磷源、制备方法和磷含量对催化剂物化性质和加氢脱氮(HDN)性能的影响。结果表明, 使用HEDP为磷源不仅可减弱活性组分-载体间的相互作用, 其结构中的羟基还可与MWH产生的H₂WO₄形成氢键而吸附在H₂WO₄表面, 抑制H₂WO₄团聚, 从而实现WO₃的高分散。MWH快速均匀加热的特点可以有效抑制H₂WO₄的过度生长, 并促进其在Al₂O₃表面的均匀快速分散, 使得以HEDP为磷源制备的W/Al₂O₃中WO₃的分散度和HDN活性远高于浸渍法制备的相同磷源、磷含量和金属含量的催化剂。MWH法制备的磷质量分数为3%的催化剂兼具高的WO₃分散度和弱的WO₃-Al₂O₃相互作用, 有最佳的HDN活性。     

Effect of method of preparation on activity of Pd/Al2O3 monolith catalysts

Pd/Al₂O₃ monolithic catalyst of different washcoat thicknesses were prepared by two methods and tested for the activity of hydrogenation of α‐methyl styrene. These catalysts were prepared by two methods; either the palladium was impregnated on γ‐alumina and this Pd/Al₂O₃ powder was used to prepare the slurry for washcoating (Cat 1) or γ‐alumina washcoating was followed by impregnation of palladium (Cat 2). The effect of slurry concentration, pH of the slurry, and addition of binders on the catalyst properties was investigated. The monolithic catalysts were characterised by determination of metal dispersion, surface area, scanning electron microscopy, and weight loss of washcoat during ultrasonication. Well‐adhered washcoats were obtained with slurry prepared using milled γ‐alumina, whereas the adhesion of the washcoat prepared using Pd/Al₂O₃ powders was very poor. Addition of binders significantly improved the adhesion of the washcoats prepared from Pd/Al₂O₃. Metal dispersion for Cat 2 decreased with washcoat loading but did not change with loading for Cat 1. The activity tests were conducted at different washcoat loadings and the productivity of the monolithic catalyst prepared in both methods has been compared.     

High activity Ni-Mo/C hydrodesulfurization catalyst: Comparison with commercial Ni-Mo/Al2O3 catalyst at increased hydrogen pressure

Hydrodesulfurization catalysts Ni-Mo/C were prepared using active carbon extracted by various solvents. A special feature of the comparison with conventional alumina-supported catalyst was the use of increased hydrogen pressure of 1.6 MPa and the utilization of a commercial Ni-Mo/Al₂O₃ sample. The best Ni-Mo/C catalyst was 3.6 times more active than the Ni-Mo/Al₂O₃ reference catalyst. Therefore, better performance of carbon-supported sulfides is not limited to the region of low pressure as suggested by some previous authors.     

Hydrogenation of 9-octadecenoic acid by Ru−Sn−Al2O3 catalysts: Effects of catalyst preparation method

Evaluation of the method of preparation and the sequence of metal incorporation onto the catalyst showed that they had profound effects on the catalytic behavior of Ru−Sn−Al₂O₃ catalysts used in the selective hydrogenation of oleic acid to 9-octadecen-1-ol. When Ru was loaded first onto the support and then followed by Sn, the catalyst had lower activity but greater ability to preserve the unsaturated bond. On the other hand, when the sequence of loading was reversed, the behavior of the catalyst changed correspondingly, i.e., the catalyst showed higher activity but poorer ability to protect the unsaturated bond. The metal particles incorporatedvia the sol-gel method were finely and evenly distributed on the support. As such, they were more readily shielded by the second metal particles that were subsequently incorporatedvia the impregnation process. When both metals were loadedvia the sol-gel process, the best result was obtained with superior performance in activity, as well as selectivity in the preservation of double bond.     

新型Pt/Al2O3苯加氢催化剂研制

在模拟苯加氢制环己烷工业装置建成的催化剂原粒度活性评价装置上，研究气相苯加氢制环己烷的Pt/Al₂O₃催化剂，主要考察催化剂制备方法、Al₂O₃载体物化性能和不同竞争吸附剂对催化剂性能的影响，提出了苯加氢制环己烷最佳的催化剂推荐工艺操作条件。与参比样对比表明，研制的Pt/Al₂O₃苯加氢催化剂性能达到参比催化剂的水平，催化剂侧压强度明显高于参比催化剂。