CATALYTIC HYDROTREATMENT OF COAL-DERIVED NAPHTHA

ABSTRACT

ABSTRACT A naphtha derived from the liquefaction of a subbituminous (Black Thunder) or a bituminous coal (III. #6) was hydrotreated on a pilot plant scale, to provide a feedstock sufficiently low in heteroatoms for further studies in reforming. Two commercial catalysts, a Ni/Mo and a Co/Mo on alumina, were employed in the processing of the naphtha samples. The Black Thunder naphtha was processed for over 120?hours, twice using the Co/Mo catalyst and once using the Ni/Mo catalyst. For this naphtha, the removal of nitrogen was extremely difficult using the catalysts and conditions employed in this study. An average of 51.6% of the nitrogen was removed during each of the three passes. The oxygen compounds in this naphtha were relatively easily removed. During the first pass over the Co/Mo catalyst, 94.0% of the oxygen was removed.     

Synthesis of carbon nanotubes by CCVD of natural gas using hydrotreating catalysts

Carbon nanotubes have been successfully synthesized using the catalytic chemical vapor deposition (CCVD) technique over typical refining hydrotreating catalysts (hydrodesulfurization and hydrodenitrogenation) containing Ni–Mo and Co–Mo supported on Al₂O₃ catalysts at 700°C in a fixed bed horizontal reactor using natural gas as a carbon source. The catalysts and the as-grown CNTs were characterized by transmission electron microscopy, HRTEM, X-ray diffraction patterns, EDX and TGA–DTG. The obtained data clarified that the Ni–Mo catalyst gives higher yield, higher purity and selectivity for CNTs compared to Co–Mo catalyst. XRD, TEM and TGA reveal also that the Ni–Mo catalyst produces mostly CNTs with different diameters whereas the Co–Mo catalyst produces largely amorphous carbon.     

合成气氢源下悬浮床加氢反应焦炭及催化剂特性分析

在高压釜中,合成气气氛下考察了克拉玛依减压渣油在不同分散型催化剂作用下的裂化反应,对反应前后催化剂的存在形态进行了光学显微扫描(SEM)分析和X射线衍射(XRD)分析。实验结果表明,催化剂存在的主要作用是抑制生焦和抑制过度裂化,改善产品分布。催化剂和焦的XRD分析谱图中没有检测到钼的硫化物形式,而在二元钼钴复合催化剂的焦XRD谱图中检测到非化学计量的CoMoS_x;焦的SEM分析表明,催化剂的存在有利于抑制焦炭颗粒的长大,水溶性催化剂作用下焦炭颗粒最小,颗粒尺寸约1μm。水溶性二元复合催化剂的总体催化性能优于相应的一元水溶性催化剂和油溶性催化剂,所选用的几种催化剂的活性从大到小的顺序为:Mo/CoMo/NiCoNaphNiNaphCo(NO_3)_2,Ni(NO_3)_2AMT。     

油溶性催化剂在渣油悬浮床加氢反应中的加氢抑焦作用

合成了油溶性Mo、Ni催化剂,并将两种单金属催化剂进行复配形成Mo/Ni复配催化剂,采用FT-IR、AAS分析方法对合成催化剂进行表征,在考察Mo、Ni及Mo/Ni复配催化剂油溶性的基础上,对不同催化剂在KLAR悬浮床加氢反应中的加氢效果进行考察,并与临氢热烈化反应结果进行对比。结果表明：Mo、Ni催化剂中的活性组分Mo、Ni质量分数分别为5.60%、5.86%;Mo、Mo/Ni、Ni催化剂的I值(单位生焦轻油收率)逐渐降低,说明它们的加氢抑焦效果依次减弱;而且Mo/Ni复配催化剂表现出了一定的协同效应,其在KLAR悬浮床加氢反应中可以成为生焦载体,延缓焦粒的富集、长大。     

Synthesis, Characterization, and Evaluation of Mesoporous MCM-41-supported Molybdenum Hydrotreating Catalysts

Mesoporous MCM-41 material with high surface area and narrow pore size distribution was synthesized and used as a support for Mo, CoMo, and NiMo catalysts. The molybdenum loading was varied from 2-14 wt% on MCM-41. On 10 wt% Mo/MCM-41, the promoter Co or Ni concentration was varied from 1-5 wt%. All the catalyst samples were characterized by surface area, low temperature oxygen chemisorption, x-ray diffraction (XRD), and temperature programmed reduction methods. Characterization results show that Mo is well dispersed on MCM-41 up to 10 wt%. The catalytic activities were evaluated for thiophene hydrodesulphurization (HDS), cyclohexene hydrogenation (HYD), and furan hydrodeoxygenation (HDO). All three catalytic functionalities vary in a similar manner to that of oxygen chemisorption as a function of Mo loading, indicating that there is a correlation between oxygen uptake and catalytic sites. The activities of these catalysts were compared with γ-Al₂O₃- and amorphous SiO₂-supported catalysts. It was found that MCM-41-supported Mo catalysts displayed superior activities.     

含助剂Ni(Co)磷化钨催化剂柴油加氢精制性能

 采用共浸渍和氢气程序升温还原的方法,以γ-Al2O3为载体,分别制备了WO3负载量为30%的含助剂Ni、Co和Ni/Co双助剂的磷化钨催化剂,对催化剂进行了XRD、BET和TG表征,评价了催化剂的柴油HDS和HDN活性。结果表明,Co和Ni均对磷化钨催化剂催化柴油HDS反应有助催化作用;而加入Co和适量的Ni对磷化钨催化剂催化柴油HDN反应有利。反应温度为360℃时,分别加有5%质量分数助剂Ni和助剂Co的2个磷化钨催化剂上柴油HDS转化率分别为59.15%和58.24%,而其上柴油HDN转化率分别为55.41%和66.79%。Ni、Co质量分数分别为3%和1%的双助剂磷化钨催化剂具有相对最高的柴油HDS和HDN活性,反应温度为360℃时,其HDS与HDN转化率分别达到62.44%和57.61%。催化剂对柴油的HDS和HDN催化活性不仅与载体表面W物种的磷化程度及活性组分的分散度有关,具有类似-Al-O-W-P结构的物种可能也是影响反应性能的一个重要因素。     

多组份加氢催化剂中TiO_2的竞争吸附效应

用X光能谱定量分析了钼,钴和镍在Al_2O_3-TiO_2载体和预浸TiO_2的Al_2O_3载体上的径向浓度分布。并与Mo、Co、Ni/Al_2O_3催化剂的活性组份分布特征做了比较。实验数据表明钼、钴和镍诸组份相对富集在二氧化钛的高浓度区,证明了二氧化钛对钼、钴和镍的竞争吸附效应及其对浓度分布的影响。     

Synthesis,Characterization, and Evaluation of Mesoporous MCM-41-supported Molybdenum Hydrotreating Catalysts

Abstract

Mesoporous MCM-41 material with high surface area and narrow pore size distribution was synthesized and used as a support for Mo, CoMo, and NiMo catalysts. The molybdenum loading was varied from 2–14 wt% on MCM-41. On 10 wt% Mo/MCM-41, the promoter Co or Ni concentration was varied from 1–5 wt%. All the catalyst samples were characterized by surface area, low temperature oxygen chemisorption, x-ray diffraction (XRD), and temperature programmed reduction methods. Characterization results show that Mo is well dispersed on MCM-41 up to 10 wt%. The catalytic activities were evaluated for thiophene hydrodesulphurization (HDS), cyclohexene hydrogenation (HYD), and furan hydrodeoxygenation (HDO). All three catalytic functionalities vary in a similar manner to that of oxygen chemisorption as a function of Mo loading, indicating that there is a correlation between oxygen uptake and catalytic sites. The activities of these catalysts were compared with γ-Al₂O₃- and amorphous SiO₂-supported catalysts. It was found that MCM-41-supported Mo catalysts displayed superior activities.     

FCC馏分油在MoP/HZSM-5催化剂上临氢芳构化研究

制备了MoP/HZSM-5催化剂，采用XRD进行表征。在反应温度400℃、压力1.0MP、体积空速1.0h-1、氢油比400:1的条件下，在小型固定床反应装置上进行催化裂化汽油中间馏分(50～100℃)的芳构化反应，考查了不同钼质量分数、n(Mo):n(P)的摩尔比和温度对反应的影响。结果表明，钼质量分数及n(Mo):n(P)的摩尔比对反应有明显的影响，适当增加磷含量能提高催化剂性能。MoP/HZSM-5在钼的质量分数为3%、n(Mo):n(P)=1.5，反应温度为400℃时，改性催化剂芳构化活性最佳,液相产品中芳烃质量分数为65.43%,烯烃质量分数为5.42%，液收为61.04%。     

Can Mesoporous TiO<Subscript>2</Subscript>-Al<Subscript>2</Subscript>O<Subscript>3</Subscript>-Supported NiMoS OR CoMoS Effectively Perform in Ultra-Deep Desulfurization of Gas Oil?

Waste aluminum foil was used for preparation of mesoporous TiO₂-Al₂O₃ using starch as a textural modifier. The catalytic species, Mo and Ni or Co were loaded onto the mesoporous support, following incipient wetness sequential impregnation. To gain an insight into the pore dimensions effect, Ni and Mo species with the same mass ratio were loaded onto the TiO₂-Al₂O₃, prepared from analytical grade chemicals without templating. TPR spectra, TEM images and BET analysis showed how the promoter (Ni or Co), TiO₂ and the template (starch) affect the ease of reduction of Mo species, the morphology of the active MoS₂ phase and the pore dimensions of the catalysts. The catalysts were employed in hydro-desulfurization process of gas oil using a fixed bed down flow microreactor at varying operating conditions, viz., temperature (320–400°C), Liquid hourly space velocity (0.5–4 h^–1), H₂/oil ratio of 450 v/v, and 6 MPa operating pressure. The results showed that the promotion effect prevails over the textural effect, where Ni promoted catalyst (with lower surface parameters) exhibits higher activity than Co promoted one. The dual layer catalytic bed system achieved the sulfur level less than 10 ppm.     

催化裂化汽油选择性加氢脱硫催化剂RSDS-1的开发

介绍了用于催化裂化汽油选择性加氢脱硫催化剂RSDS-1的研究开发，考察了载体、活性组元、金属原子比以及助剂对催化剂选择性的影响。研究结果表明，催化裂化汽油中烯烃的加氢饱和受扩散限制；Co—Mo组合对烯烃饱和的能力相对较弱；较高的Co／Mo原子比有利于提高催化剂选择性；助剂的加入对催化剂选择性有明显的影响；RSDS—1催化剂用于催化裂化汽油选择性脱硫，对不同原料油适应性好，脱硫率可达80％，RON损失小于2个单位，且可长周期稳定运转。     

Co改性Mo/HZSM-5催化剂的甲烷无氧芳构化催化性能研究

以Mo/HZSM-5（硅铝比38）为基础,分别添加第二活性组分Mg,Ni,Cr,Cu,Zn,Co,采用共浸渍法制备了一系列的二元催化剂,考察这些催化剂对甲烷无氧芳构化过程的催化性能,结果表明,在Mo/HZSM-5催化剂中添加Co可提高其对甲烷无氧芳构化过程的催化活性。进一步研究了不同Co负载量的二元催化剂对甲烷无氧芳构化过程的催化性能,并采用XRD,NH3-TPD,TG-DTA等手段对催化剂进行表征,结果表明： 催化剂中添加Co后能够提高苯的生成速率;添加0.7 %（w）的Co时制备的6%Mo-0.7%Co/HZSM-5催化剂中Co与Mo具有良好的协同作用,与6% Mo/HZSM-5催化剂相比,不但减缓了积炭的生成,提高了催化剂的稳定性,而且提高了催化剂的催化活性,苯收率提高2%~5%;催化剂中添加Co后,酸强度及酸量得到明显改善,弱酸量与强酸量比例适中,Co化合物与Mo化合物能够均匀分散在分子筛表面,从而可提高催化剂的催化活性。     

以全硅MCM—41为载体制备W系深度加氢脱硫催化剂

用全硅MCM－41担载Ni-W和Co-W制备了深度加氢脱硫催化剂,并在中压固定床反应器上分别考察了对二苯并噻吩（DBT）和高硫直接馏柴油的加氢脱硫性能。结果表明,全硅MCM－41担载制成的W系催化剂表现出很高的加氢脱硫活性,其中Ni-W/MCM-41活性高于Co-W/MCM-41,但两类催化剂的最佳Ni(Co)/W原子比均为0．75。从加氢脱硫产物分布看,两类催化剂的脱硫反应路径不同,在Co-W/MCM-41上主要通过氢解脱硫,而在Ni-W/MCM-41上则是通过氢解以及先经芳环加氢后脱硫的两条路径来进行,对Ni-MCM-41来说,加氢活性随温度升高而升高。     

原位溶胶-凝胶法制备深度加氢脱芳催化剂NiO-MoO3/SiO2-Al2O3-TiO2

 利用原位溶胶-凝胶技术制备不同SiO₂含量及Ni/Mo摩尔比的负载型NiO-MoO₃/SiO₂-Al₂O₃-TiO₂深度加氢脱芳烃催化剂。采用ICP、N₂吸附-脱附等温线及XRD方法,表征催化剂的物化性质、结构特征;采用TPD、TPR手段,考察催化剂的酸强度以及活性组分Ni与载体的相互作用;在固定床加压连续微反装置上,以航空煤油为原料,进行深度加氢脱芳催化反应,考察催化剂的活性和稳定性。结果表明,原位溶胶-凝胶法制备的Ni基负载型催化剂的操作工艺简单,且不改变原载体的表面结构特征,通过表面涂硅处理及改变SiO₂含量,达到调节催化剂酸强度的目的;MoO₃的加入能够增加Ni原子的活性位,减弱其与载体的相互作用。催化剂的总金属含量较高(30%)时,显示出良好的加氢脱芳烃性能及稳定性。航空煤油深度加氢脱芳烃产品油中总芳烃的质量分数小于0.002%。     

助剂对Ni/SiO2催化剂结构和间二硝基苯加氢性能的影响

采用等体积分步浸渍法，制备了添加Mg、Cu、Co、Ce、La助剂的Ni／SiO2催化剂，用于间二硝基苯加氢制间苯二胺反应，并采用XRD和TPR等手段表征了催化剂的物理化学性质。结果表明，助剂Mg、Cu、Co、Ce的加入均不同程度地抑制了催化剂的加氢活性；La的加入显著提高了催化剂的活性和选择性，在反应压力2．6MPa、反应温度373K时，反应1h，间二硝基苯转化率和间苯二胺产率分别为97．1％和93．5％。XRD和TPR的结果表明，稀土氧化物La2O3可使催化剂中Ni晶粒度变小，分散度增加，且能大大削弱载体与Ni物种之间的相互作用，从而增加催化剂中活性Ni物种的数目，增大催化剂的活性和选择性。     

甲醇气相羰化非铑非卤素新催化体系研究 Ⅰ.硫化的CoMo/C系催化剂制备

制备了一系列硫化的负载型ＣｏＭｏ催化剂，在没有添加任何卤素作促进剂的情况下，研究了它们的甲醇气相羰化性能。实验表明，活性炭是最佳载体；硫化的Ｍｏ／Ｃ本身无羰化活性，但能促进甲醇的转化，Ｃｏ有利于羰化产物生成；Ｃｏ、Ｍｏ质量含量各为１０％时，硫化的ＣｏＭｏ／Ｃ催化剂具有较好的活性与选择性；反应温度为３００℃时，催化剂的羰化活性最高。当空速为１６００Ｌ／（ｋｇ·ｈ）、甲醇进料浓度为８．４ｍｏｌ％时，甲醇转化率达３１．５％，醋酸甲酯时空收率高达０．５６９ｍｏｌ／（ｋｇ·ｈ）。     

非负载Co-Mo催化剂的制备、表征与加氢脱硫活性评价

采用溶胶-凝胶法制备了Co-Mo超细复合氧化物,进而制得了非负载型Co-Mo催化剂;采用XRD、IR、BET、SEM等考察了n(A1):n(Co+Mo)、n(Mo):n(Co+Mo)和CA(柠檬酸)/(Co+Mo)的摩尔比对对应催化剂的表面形貌、结构和催化性能的影响.结果表明:制备的非负载催化剂以β-CoMoO<,4>...     

Hydrotreating of gasoline and diesel oil fractions over modified alumina/zeolite catalysts

This paper deals with hydrotreating of straight-run gasoline (SRG) and diesel oil fractions (DOF) over new Ni (Co) containing alumina/zeolite catalysts, modified by transition metals (W and Mo) with the addition of P and Ce elements. In hydrotreating of the DOF, the CoO-WO₃-CAR catalyst has the highest hydrodesulphurization activity that reaches 97.2% at 400?°C, P?=?4MPa and V?=?2h^?1. Moreover, increasing of pressure until 5?MPa leads to reducing of the sulfur content up to 0.0007%. The greatest decrease in the pour (?58.9?°C) and the cloud (?56.7?°C) points during the hydrotreating of the DOF is observed using the NiO-MoO₃-CAR catalyst. The octane number of SRG after hydrotreating over the NiO-MoO₃-CAR catalyst rises up to 88.6. Obtained results clearly show that using synthesized catalysts, motor fuel with Euro-5 standard could be obtained.     

Hydrotreating Activity of Heavy Gasoil over NiMo/γ-Al2O3-TiO2

Different γ-Al₂O₃-TiO₂ catalysts were tested in a pilot plant fixed-bed reactor in order to evaluate the effect of atomic ratio (Ni/Ni + Mo) on hydrotreating activity of heavy gasoil FCC feed. Hydrotreating reactions were carried out at three temperatures (330, 365, and 400°C) and LHSV of 6 h^-1. Studies of atomic ratio were done varying Ni amounts (2, 2.4, and 2.95 wt%) whereas molybdenum loading was kept constant (6 wt%) for all catalysts, the behavior of these catalysts was compared with a reference catalyst containing 11.5 wt% of Mo and 2.95 wt% of Ni, which was evaluated at the same conditions. All catalysts were prepared by incipient impregnation method over γ-Al₂O₃-TiO₂ (Ti = 5.6 wt%). Experimental results showed correlation between the atomic ratio (Ni/Ni + Mo) and the best results for hydrodemetallization where found for the catalyst with atomic ratio of (Ni/Ni + Mo) = 0.45.     

镍钼配比对镍钼氮化物结构和丙烷氨氧化反应性能的影响

以钼酸铵和硝酸镍为原料,采用共沉淀法合成镍钼金属氧化物,再经过程序升温氮化反应合成镍钼双金属氮化物。利用XRD,Visible-Raman,FTIR,H2-TPR对镍钼氧化物及氮化物晶体结构及氧化还原性进行表征,并考察了丙烷在镍钼氮化物催化剂上的氨氧化反应性能。结果表明：通过控制化学试剂镍钼配比能够定向合成Ni2Mo3N或定向合成g-Mo2N和Ni2Mo3N两相共存的镍钼氮化物;两相共存的镍钼氮化物催化剂能够产生相互协同作用,有利于催化丙烷氨氧化反应,其催化活性和丙烯腈选择性明显优于单一晶相的g-Mo2N或Ni2Mo3N;由镍钼摩尔比为3/2的化学试剂制得的镍钼氮化物催化剂表现出最优的催化性能,在773 K时丙烷转化率为75.0%,丙烯腈选择性为38.6%,产率为28.95%。