煤的一段加氢液化的催化剂

煤的一段加氢液化使用的催化剂有可弃性催化剂,铁和钼氧化物及溶于水或油的催化剂和浸渍催化剂,其中以Co-Mo/Al_2O_3,Ni-Mo/Al_2O_3和钼酸铵为最广泛;黄铁矿能促进煤向油的转化,但却降低了脱硫率:Fe(OH)3-MoO_3-S在较低和较高温度下都是一种较活泼的催化剂;SnMo混合物明显优于纯SnO_2或无助催化剂的MoO_3/Al_2O_3;硫化的Mo(CO)_6是一种性能很好的煤加氢液化催化剂。     

Ni-Mo/Al_2O_3催化剂对废轮胎液化油催化加氢特性研究

以Ni-Mo/Al_2O_3为催化剂,利用1.8 L高压反应釜考察反应温度和氢压对废轮胎液化油加氢转化及脱硫、脱氮效果的影响。结果表明,通过提高反应温度和氢压,可以促进液化油中重组分的转化和硫氮元素的脱除,反应温度和氢压对于脱硫效果影响较明显,而对脱氮效果影响较小。在反应温度410℃、氢压8 MPa和停留时间2 h条件下,重组分全部转化,轻质油收率78%,脱硫率和脱氮率分别达到93.60%和35.63%,其中,汽油馏分中硫、氮含量较低,分别为10.72 mg·L~(-1)和12.04 mg·L~(-1)。     

乙二胺四乙酸对NiMo/Al_2O_3催化剂加氢脱氮性能的影响

以氧化铝为载体,Ni和Mo为金属活性组分,添加不同含量乙二胺四乙酸,采用等体积浸渍法制备系列Ni Mo(x)/Al_2O_3(x为乙二胺四乙酸与Ni物质的量比)重质油加氢处理催化剂,考察乙二胺四乙酸加入量对催化剂加氢脱氮性能的影响,并采用N_2物理吸附-脱附、XRD和HRTEM等对催化剂进行表征。结果表明,乙二胺四乙酸的加入增强了金属组分与氧化铝载体间的相互作用,降低了MoS_2活性相的堆垛层数和片层长度,促进了活性相的分散。乙二胺四乙酸与Ni物质的量比为0.5时,MoS_2活性相堆垛层数和片层长度达到良好的结合,对应的催化剂Ni Mo(0.5)/Al_2O_3具有最优的加氢脱氮性能。     

CoO/MoO_3/Al_2O_3复合物催化H_2O_2氧化模型柴油脱硫

以γ-Al_2O_3为载体,通过等体积浸渍法,制备了CoO/MoO_3/Al_2O_3催化剂。采用N_2吸附-脱附、X射线衍射(XRD)对CoO/MoO_3/Al_2O_3进行表征分析。以二苯并噻吩(DBT)、4-甲基二苯并噻吩(4-MDBT)为模型柴油的有机硫化物,30%的过氧化氢为氧化剂,考察了CoO/MoO_3/Al_2O_3催化剂的催化性能,并且研究了不同Mo/Co摩尔比、催化剂焙烧温度、投加量、反应时间及温度对氧化脱硫的影响。实验结果表明:H_2O_2-CoO/MoO_3/Al_2O_3构成的氧化体系能有效氧化模型柴油中的有机硫化物,DBT和4-MDBT脱硫率分别达到98.8%、93.4%;Mo/Co摩尔比、催化剂焙烧温度、投加量、反应时间及温度对有机硫化物的氧化脱硫均有影响;CoO/MoO_3/Al_2O_3催化剂经过再生处理后可重复使用,具有良好的稳定性。     

国外石油炼制技术新进展（下）

渣油加氢处理过程用于FCC或焦化装置原料预处理和生产低硫燃料油。该过程使用的老催化剂为Co—Mo/Al_2O_3。新一代催化剂是具有特殊孔结构和颗粒度的Co—Mo和Ni—Mo/Al_2O_3系统。该系统可改善多床层反应器的加氢脱硫、加氢脱氮和加氢裂化功能。其作用是提高抗金属性能,延长循环周期,提高馏分油转化率,提高脱硫、脱氮和脱金     

NiO/Al_2O_3基催化剂的TPR特性研究

NiO/Al_2O_3基催化剂用于替代贵金属催化剂,被广泛应用于石油和石化领域生产过程的加氢、脱硫和脱氮。采用TPR方法,研究不同Ni含量NiO/Al_2O_3及不同载体的催化剂还原特性。结果表明,NiO/Al_2O_3催化剂在10%H_2-Ar气氛下,还原温度范围较宽,为(300~800)℃,其中,(500~600)℃还原速率最大;随着NiO含量的增加,起始还原温度降低,还原耗氢量按比例增加;以MgO为载体的NiO催化剂还原呈现双峰特征,以SiO2和TiO2为载体的NiO催化剂的初始还原温度比NiO/Al_2O_3催化剂降低(100~200)℃。     

按序使用矿物催化剂和加氢处理催化剂的两段煤液化

两段煤液化和单段煤液化工艺相比,在产率上有显著的改进。本文所建议的两段工艺操作中,在第一段用价廉易得的矿物质催化剂,在第二段用商品加氢处理催化剂。分别在450℃和425℃进行的单段加工工艺均证明;金属硫化物(例如硫铁矿)对增高产油率是有效的。在两段加工工艺中,一段温度为450℃,二段在410℃,以及一段用黄铁矿催化剂,二段用NiMo/Al_2O_3催化剂是产油(戊烷可溶物)最有效的组合次序。两段温度均在425℃,经硫化的液化残留灰分或黄铁矿用作一段催化剂,得到油的百分率最高。由产品溶解度分布所表明的改进是通过反应产物的蒸馏曲线来证实的。在呈颗粒状的NiMo/Al_2O_3中,孔隙扩散限制的迹象是很明显的。为了达到最大产率,必需改变催化剂的结构。     

煤液化中油馏分加氢精制和加氢裂解的研究

本文采用两段加氢精制工艺,对煤液化中油馏分的精制进行了系统的研究。研究发现,使用3665、3822两种催化剂,能一次获得符合加氢裂解要求的产品,脱氮率达99.9％。研究证明,两段精制工艺适合煤液化中油的加氢脱杂原子,第一段主要作用是进行加氢饱和,可采用活性较低的催化剂或在缓和的条件下进行,第二段作用是开环加氢脱氮。本文还研究了反应条件对脱氮率、H/C原子比、产品族组成、芳香度等的影响。     

负载型NiMo加氢处理催化剂氧化物载体研究进展

以NiMo在加氢精制中的应用为线索,按催化剂载体的不同,简介了以单一氧化物和复合氧化物为载体的催化剂的制备方法,总结了NiMo为活性组分,氧化物为载体的加氢精制催化剂的应用进展。按照载体的不同,从单一氧化物载体Al_2O_3,TiO_2和SiO_2,以及复合氧化物载体角度总结了催化剂在加氢精制中的应用。氧化物载体具有热稳定性好,酸碱性适宜的特点,一直是人们研究的重要内容。     

有序介孔材料Al-FDU-12的合成及其加氢精制应用

采用原位合成法合成了不同硅铝原子比（Si/Al=50、40、30、20、10）的Al-FDU-12介孔材料,进一步浸渍镍钼活性金属制备了催化剂。通过小角X射线衍射（XRD）、广角XRD、N₂吸附-脱附、扫描电镜（SEM）、透射电镜（TEM）和紫外等表征手段对材料及催化剂做了相应的表征,并且考察了不同硅铝比的NiMo/Al-FDU-12催化剂在催化裂化柴油中的加氢脱硫脱氮性能。结果表明,FDU-12介孔材料孔径、孔容以及比表面积大,活性金属分散度高。铝改性后的NiMo/Al-FDU-12催化剂加氢脱硫、脱氮活性得到显著提高。当反应条件为温度350℃、氢油体积比600、压力5.0MPa、质量空速（WHSV）1.0h^-1、硅铝比20时,催化剂的加氢脱硫脱氮活性最高,脱硫率可达98.9%,脱氮率可达95.3%。在相同反应条件下,工业催化剂催化柴油加氢脱硫、脱氮率低于NiMo/AF-20以及NiMo/AF-10催化剂。因此,铝改性后的FDU-12材料具有良好的工业应用前景。     

Hydrotreating of gas oil on SBA-15 supported NiMo catalysts

The siliceous and the metal substituted (B or Al)-SBA-15 molecular sieves were used as a support for NiMo hydrotreating catalysts (12 wt.% Mo and 2.4 wt.% Ni). The supports were characterized by X-ray diffraction (XRD), scanning electron microscopy and N₂ adsorption–desorption isotherms. The SBA-15 supported NiMo catalysts in oxide state were characterized by BET surface area analysis and XRD. The sulfided NiMo/SBA-15 catalysts were examined by DRIFT of CO adsorption and TPD of NH₃. The HDN and HDS activities with bitumen derived light gas oil at industrial conditions showed that Al substituted SBA-15 (Al-SBA-15) is the best among the supports studied for NiMo catalyst. A series of NiMo catalysts containing 7–22 wt.% Mo with Ni/Mo weight ratio of 0.2 was prepared using Al-SBA-15 support and characterized by BET surface area analysis, XRD and temperature programmed reduction and DRIFT spectroscopy of adsorbed CO. The DRIFT spectra of adsorbed CO showed the presence of both unpromoted and Ni promoted MoS₂ sites in all the catalysts, and maximum “NiMoS” sites concentration with 17 wt.% of Mo loading. The HDN and HDS activities of NiMo/Al-SBA-15 catalysts were studied using light gas oil at temperature, pressure and WHSV of 370 °C, 1300 psig and 4.5 h⁻¹, respectively. The NiMo/Al-SBA-15 catalyst with 17 wt.% Mo and 3.4 wt.% of Ni is found to be the best catalyst. The HDN and HDS activities of this catalyst are comparable with the conventional Al₂O₃ supported NiMo catalyst in real feed at industrial conditions.     

Effect of phosphorus addition on the hydrotreating activity of NiMo/Al2O3 carbide catalyst

A series of phosphorus promoted γ-Al₂O₃ supported NiMo carbide catalysts with 0–4.5 wt.% P, 13 wt.% Mo and 2.5 wt.% Ni were synthesized and characterized by elemental analysis, pulsed CO chemisorption, BET surface area measurement, X-ray diffraction, near-edge X-ray absorption fine structure, DRIFT spectroscopy of CO adsorption and H₂ temperature programmed reduction. X-ray diffraction patterns and CO uptake showed the P addition to NiMo/γ-Al₂O₃ carbide, increased the dispersion of β-Mo₂C particles. DRIFT spectra of adsorbed CO revealed that P addition to NiMo/γ-Al₂O₃ carbide catalyst not only increases the dispersion of Ni-Mo carbide phase, but also changes the nature of surface active sites. The hydrodenitrogenation (HDN) and hydrodesulfurization (HDS) activities of these P promoted NiMo/γ-Al₂O₃ carbide catalysts were performed in trickle bed reactor using light gas oil (LGO) derived from Athabasca bitumen and model feed containing quinoline and dibenzothiophene at industrial conditions. The P added NiMo/γ-Al₂O₃ carbide catalysts showed enhanced HDN activity compared to the NiMo/γ-Al₂O₃ catalysts with both the feed stocks. The P had almost no influence on the HDS activity of NiMo/γ-Al₂O₃ carbide with LGO and dibenzothiophene. P addition to NiMo/γ-Al₂O₃ carbide accelerated CN bond breaking and thus increased the HDN activity.     

Hydrodesulfurization and Hydrodenitrogenation Kinetics of a Heavy Gas Oil over NiMo/Al2O3 Catalysts

1 Introduction The increasing demands of high quality and environment-friendly petroleum products require refineries to treat more heavy oil and residue in the worldwide. Athabasca bitumen derived heavy gas oil(HGO) is a typical feedstock comprising high nitrogen and sulfur heteroatomic compounds, which results in many problems in utilization, such as reducing the stability of fuels, causing storage problems and air pollution. So they need to be removed before being treated in the following u…     

A series of NiMo/Al2O3 catalysts containing boron and phosphorus: Part II. Hydrodenitrogenation and hydrodesulfurization using heavy gas oil derived from Athabasca bitumen

The hydrodenitrogenation (HDN) and hydrodesulfurization (HDS) activity of a series of NiMo/Al₂O₃ catalyst containing boron (B) and phosphorus (P) were tested in a trickle bed reactor using heavy gas oil derived from Athabasca bitumen. Detailed characterization of these catalysts is given in Part I of this paper. Addition of B and P caused the formation of extremely strong acid sites on the catalyst and enhanced its HDN activity. The total (TN), basic (BN) and non-basic nitrogen (NBN) conversions increased from 61.9 to 78.0 wt.%, from 78.9 to 93.0 wt.% and from 52.8 to 70.0 wt.%, respectively, with the increase in B concentration from 0 to 1.7 wt.% to NiMo/Al₂O₃ catalyst. Similarly, TN, BN and NBN conversions increased from 61.9 to 78.4 wt.%, from 78.9 to 91.0 wt.%, and from 52.8 to 71.6 wt.% with the addition of 2.7 wt.% P. Though the addition of B and P to NiMo/Al₂O₃ catalyst did not show any significant effect on S conversion, the HDN and HDS activities of the catalyst containing 1.7 wt.% B and the one containing 2.7 wt.% P are comparable to those of a commercial catalyst. The activity over extended period indicated that catalysts L and K were more stable (lower deactivation rate) in terms of nitrogen removal activity than catalyst B (reference catalyst). On the other hand, the stability for sulfur removal was comparable with catalyst B. Selected catalysts after use were characterized using BET surface area, TPR, TPD and SEM techniques which were correlated further with their activities.     

Analysis of the hydrotreatment of Maya heavy crude with NiMo catalysts supported on TiO2-Al2O3 binary oxides: Effect of the incorporation method of Ti

Heavy Maya crude has been hydrotreated with NiMo/alumina-titania catalysts in which titania was incorporated by two different methods. Titania added to boehmite followed by calcination in order to promote formation of Ti–O–Al bonds, and Ti added to alumina in order to promote the formation of TiO₂ structures on the surface. The reaction results indicate that hydrodesulfurization (HDS), hydrodemetallization (HDM) and hydrodenitrogenation (HDN) activities are improved by the incorporation of Ti to the catalyst. In all cases, catalysts prepared by the method leading to the formation of surface TiO₂ structures show superior performance in the three functionalities (HDS, HDM and HDN). Raman analysis of the supports gives clear evidence of the differences in Ti oxide structures on the surface. The characterization of the catalysts indicates that Ti-modified catalysts have increased surface acidity (evaluated by pyridine adsorption) and greater number of coordinatively unsaturated sites (titrated by NO adsorption). Ti-containing catalysts seem to be also more stable with time-on-stream.     

Mesoporous silica–alumina as support for Pt and Pt–Mo sulfide catalysts: Effect of Pt loading on activity and selectivity in HDS and HDN of model compounds

The potential of mesoporous silica–alumina (MSA) material as support for the preparation of sulfided Pt and Pt–Mo catalysts of varying Pt loadings was studied. The catalysts were characterized by their texture, hydrogen adsorption, transmission electron microscopy, temperature programmed reduction (TPR) and by activity in simultaneous hydrodesulfurization (HDS) of thiophene and hydrodenitrogenation (HDN) of pyridine. Sulfided Pt/MSA catalysts with 1.3 and 2 wt.% Pt showed almost the same HDS and higher HDN activities per weight amounts as conventional CoMo and NiMo/Al₂O₃, respectively. The addition of Pt to sulfided Mo/MSA led to promotion in HDS and HDN with an optimal promoter content close to 0.5 wt.%. The results of TPR showed strong positive effect of Pt on reducibility of the MoS₂ phase which obviously reflects in higher activity of the promoted catalysts. The activity of the MSA-supported Pt–Mo catalyst containing 0.5 wt.% Pt was significantly higher than the activity of alumina-supported Pt–Mo catalyst. Generally, Pt–Mo/MSA catalysts promoted by 0.3–2.3 wt.% Pt showed lower HDS and much higher HDN activities as compared to weight amounts of CoMo and NiMo/Al₂O₃. It is proposed that thiophene HDS and pyridine hydrogenation proceed over Pt/MSA and the majority of Pt–Mo/MSA catalysts on the same type of catalytic sites, which are associated with sulfided Pt and MoS₂ phases. On the contrary, piperidine hydrogenolysis takes place on different sites, most likely on metallic Pt fraction or sites created by abstraction of sulfur from MoS₂ in the presence of Pt.     

The role of nickel in pyridine hydrodenitrogenation over NiMo/Al2O3

Al₂O₃ supported Mo, Ni, and NiMo/Al₂O₃ catalysts with various Ni contents were prepared to investigate the role of Ni as a promoter in a NiMo bimetallic catalyst system. The hydrodenitrogenation (HDN) reaction of pyridine as a catalytic probe was conducted over these catalysts under the same reaction conditions and the catalysts were characterized using BET surface area measurement, infrared spectroscopy, temperature programmed reduction, DRS and ESR. According to the results of reaction experiments, the NiMo/Al₂O₃ catalyst showed higher activity than Mo/Al₂O₃ catalyst in the HDN reaction and particularly the one with atomic ratio [Ni/(Ni+Mo)]=0.3 showed the best activity for the HDN of pyridine. The findings of this study lead us to suggest that the enhancement in the HDN activity with nickel addition could be attributed to the improvement in the reducibility of molybdenum and the formation of Ni-Mo-O phase.     

Deep HDS over NiMo/Zr-SBA-15 catalysts with varying MoO3 loading

In the present work, with the aim of searching for new, highly effective catalysts for deep HDS, a series of NiMo catalysts with different MoO₃ loadings (6–30 wt.%) was prepared using SBA-15 material covered with ZrO₂-monolayer as a support. Prepared catalysts were characterized by N₂ physisorption, small- and wide-angle XRD, UV–vis diffuse reflectance spectroscopy, temperature-programmed reduction, SEM-EDX and HRTEM, and their catalytic activity was evaluated in the 4,6-dimethyldibenzothiophene hydrodesulfurization (HDS). It was observed that ZrO₂ incorporation on the SBA-15 surface improves the dispersion of the Ni-promoted oxidic and sulfided Mo species, which were found to be highly dispersed, up to 18 wt.% of MoO₃ loading. Further increase in metal charge resulted in the formation of MoO₃ crystalline phase and an increase in the stacking degree of the MoS₂ particles. All NiMo catalysts supported on ZrO₂-modified SBA-15 material showed high activity in HDS of 4,6-DMDBT. The best catalyst having 18 wt.% MoO₃ and 4.5 wt.% NiO was almost twice more active than the reference NiMo/γ-Al₂O₃ catalyst. High activity of NiMo/Zr-SBA-15 catalysts and its evolution with metal loading was related to the morphological characteristics of the MoS₂ active phase determined by HRTEM.     

Preparation,characterization and hydrotreating performances of ZrO2–Al2O3-supported NiMo catalysts

A series of Al₂O₃–ZrO₂ composite supported NiMo catalysts with various ZrO₂ contents were prepared. Several techniques including XRD, SEM, N₂ physisorption, H₂-TPR, and UV–vis DRS were used for typical physico-chemical properties characterization of the ZrO₂–Al₂O₃ composite supports and their NiMo/ZrO₂–Al₂O₃ catalysts. The test results showed that the composite supports prepared by the chemical precipitation method existed as amorphous phase in the samples with insufficient contents of ZrO₂, and the incorporation of ZrO₂ into supports provided a better dispersion of NiMo species, which made their reductions become easier. The pyridine-adsorbed FT-IR results indicated that the Lewis acid sites of catalysts increased significantly by the introduction of ZrO₂ into the supports. The activities of these catalysts for diesel oil hydrodesulfurization (HDS) and hydrodenitrogenation (HDN) were evaluated in a high pressure micro-reactor system. The results showed that the ZrO₂–Al₂O₃-supported NiMo catalysts with suitable ZrO₂ contents exhibited much higher catalytic activities than that of Al₂O₃-supported one, and when the ZrO₂ contents were 15% and 5%, the NiMo/Al₂O₃–ZrO₂ catalysts presented the highest HDS and HDN activities, respectively.     

Catalytic hydrotreatment on alumina–titania supported NiMo sulphides

MoNi/Al₂O₃ catalysts have been widely used for hydrodesulphurisation of oil fractions. In order to enhance the catalytic activities for HDS and HDN, catalysts supported on titania-modified alumina carriers have been studied. The MoNi/Al₂O₃–TiO₂catalysts were characterised by benzene sorption, ammonia sorption, temperature programmed reduction, X-ray diffraction and scanning electron microscopy. The supports effect was examined by comparing thiophene conversion and sulphur or nitrogen contents in diesel oil fraction.