Synthesis,characterization and hydrotreating performance of supported tungsten phosphide catalysts

Supported tungsten phosphide catalysts were prepared by temperature-programmed reduction of their precursors (supported phospho-tungstate catalysts) in H₂ and characterized by X-ray diffraction (XRD), BET, temperature-programmed desorption of ammonia (NH₃-TPD) and X-ray photoelectron spectroscopy (XPS). The reduction-phosphiding processes of the precursors were investigated by thermogravimetry and differential thermal analysis (TG-DTA) and the suitable phosphiding temperatures were defined. The hydrodesulfurization (HDS) and hydrodenitrogenation (HDN) activities of the catalysts were tested by using thiophene, pyridine, dibenzothiophene, carbazole and diesel oil as the feedstock. The TiO₂, ?-Al₂O₃ supports and the Ni, Co promoters could remarkably increase and stabilize active W species on the catalyst surface. A suitable amount of Ni (3%–5%), Co (5%–7%) and V (1%–3%) could increase dispersivity of the W species and the BET surface area of the WP/?-Al₂O₃ catalyst. The WP/?-Al₂O₃ catalyst possesses much higher thiophene HDS and carbazole HDN activities and the WP/TiO₂ catalyst has much higher dibenzothiophene (DBT) HDS and pyridine HDN activities. The Ni, Co and V can obviously promote the HDS activity and inhibit the HDN activity of the WP/?-Al₂O₃ catalyst. The G-Ni5 catalyst possesses a much higher diesel oil HDS activity than the sulphided industrial NiW/?-Al₂O₃ catalyst. In general, a support or promoter in the WP/?-Al₂O₃ catalyst which can increase the amount and dispersivity of the active W species can promote its HDS and HDN activities.     

焙烧及还原条件对Ni2P/TiO2-Al2O3催化剂加氢脱硫性能的影响

采用溶胶-凝胶法制备了TiO₂-Al₂O₃复合载体, 以柠檬酸(CA)为络合剂采用浸渍法制备了Ni₂P负载的TiO₂-Al₂O₃复合载体催化剂, 并用 X 射线衍射(XRD)、N₂吸附比表面积(BET)测定技术对催化剂的结构和性质进行了表征, 考察了载体焙烧温度、催化剂焙烧温度、还原温度、还原压力对其进行的二苯并噻吩(DBT)加氢脱硫(HDS)性能的影响。结果表明, 升高载体焙烧温度有利于催化剂表面上活性物种的分散, 但焙烧温度过高会导致催化剂烧结, 适宜的载体焙烧温度为550℃。当还原温度为500～550℃时, 磷化镍主要以Ni₁₂P₅相形式存在, 且随着还原温度的升高, Ni₁₂P₅的衍射峰强度逐渐增强, 还原温度为700℃时, 可得到单一的Ni₂P物相。载体焙烧温度为550℃, 催化剂焙烧温度为500℃, 还原温度为700℃, 常压还原制备的Ni₂P/TiO₂-Al₂O₃催化剂具有最好的活性。在360℃、3.0MPa、氢油体积比500、液时体积空速2.0h^-1的条件下, 反应4h时, DBT转化率为99.5 %。     

CoMo/Ti-SBA-15 catalysts for dibenzothiophene desulfurization

With a view to reducing the sulfur content in diesel fuels, novel desulfurization CoMo catalysts were supported on a Ti-loaded hexagonal mesoporous SBA-15 material. The Ti-SBA-15 substrates were synthesized using triblock copolymers as structure-directing agents. Catalytic activity was assessed in the model reaction of hydrodesulfurization (HDS) of dibenzothiophene (DBT), carried out in a batch reactor at T = 623 K and with a total hydrogen pressure of 3.1 MPa. The reaction proceeds via the direct desulfurization route (main route) and the hydrogenation (HYD) pathway. The incorporation of Ti into the SBA-15 afforded catalysts that were more active than the Ti-free counterpart, due to the enhancement of the DDS route in this reaction. This difference was explained in terms of a larger number of coordinately unsaturated sites (CUS) of the metal sulfide on Ti-loaded catalysts. Under steady-state conditions, the CoMoST20 catalyst with a Si/Ti ratio of 20 was the most active among the catalysts studied. Since this catalyst exhibited both Ti⁴⁺ ions incorporated into the SBA-15 framework and separate anatase TiO₂ clusters located on its surface, the activity enhancement on this sample was explained by the larger intrinsic activity of the “Co–Mo–S” phase located on these TiO₂ nanoparticles. The Ti-SBA-15 supports and the CoMo/Ti-SBA-15 catalysts were studied by N₂ adsorption–desorption isotherms, XRD, TEM, FTIR of adsorbed pyridine and NO, UV–vis DRS, TPR, micro-Raman and XPS spectroscopy.     

Synthesis and characterization of P-modified mesoporous CoMo/HMS–Ti catalysts

A hexagonal mesoporous siliceous material with a wormhole framework structure incorporating Ti (HMS-Ti; Si/Ti atomic ratio of 40) was modified with variable amounts of phosphorous and used as support for CoMo phases. The catalysts were prepared by successive impregnation, with Mo being introduced first. The supports and catalysts were characterized by N₂ adsorption–desorption, High-resolution transmission electron microscopy, X-ray diffraction, FT-IR study of the framework vibrations, DRIFT spectra in the OH region, ¹H NMR, FT-IR spectra of adsorbed NO, micro-Raman spectroscopy and X-ray photoelectron spectroscopy. The catalysts were tested in the reaction of hydrodesulfurization (HDS) of dibenzothiophene (DBT) and their activity compared with that of a commercial P-containing CoMo/γ-Al₂O₃ catalyst. The physical and chemical characterization of the P-modified HMS–Ti substrates shows that the presence of P₂O₅ on the support surface does not change its mesoporous character, but modifies its surface properties. In addition, characterization data of the oxide catalysts show that phosphate favors the dispersion of the active phases and increases the population of octahedral Co²⁺ ions associated to Mo species. As a result, HDS activity was strongly enhanced upon P-loading, which reached a maximum of 0.64 wt%. This catalyst is 3.7 times more active than the commercial one and 2.4 times more active than its P-free counterpart. The highest activity of this catalyst was explained in terms of the specific electronic properties of its active phases and the largest Mo surface exposure on the support.     

Removal of refractory S-containing compounds from liquid fuels on novel bifunctional CoMo/HMS catalysts modified with Ti

This study shows that titanium incorporation into hexagonal mesoporous silica (HMS) material has a positive effect on the activity of supported CoMo catalysts in the hydrodesulfurization (HDS) of dibenzothiophene (DBT) and 4-ethyl,6-methyl-dibenzothiophene (4E6MDBT). All catalysts showed the highest activity in the HDS of DBT than in the HDS of 4E6MDBT. The low reactivity observed in the HDS of 4E6MDBT is caused by the steric hindrance of the two alkyl groups at positions 4 and 6. The HDS of DBT over Ti-free catalyst proceeds exclusively via the direct desulfurization (DDS) route whereas over Ti-containing catalysts proceed via DDS (main route) and hydrogenation (HYD) pathway. The catalyst with a Si/Ti = 40 (molar ratio) was the most active in the HDS of DBT. A further increase in the Ti-content led to a decrease in Brønsted acidity and the S_BET specific area of the catalysts, which implies a decrease in the bifunctional character of the catalysts. Raman spectroscopy demonstrated that Ti-incorporation into HMS material leads to a decrease in the degree of polymerization of Mo species, and this implies a better dispersion of MoS₂, in good agreement with the XPS measurements. Regarding the HDS-resistant 4E6MDBT, the HDS reaction over the Ti-free catalyst was found to proceed exclusively via the dealkylation (DA) route. After Ti-incorporation into HMS material, additional acid-catalyzed isomerization occurs. With respect to industrial sample, the catalyst with Si/Ti = 40 showed lower intrinsic activity as well as greater selectivity toward isomerization route products.     

Deep desulfurization of diesel fuels: kinetic modeling of model compounds in trickle-bed

Five catalysts with different hydrodesulfurization (HDS) and hydrogenation activity were tested in HDS of fresh crude heavy atmospheric gas oil (HAGO) (1.33 wt% S), two partially hydrotreated HAGO (1100 and 115 ppm S) and two model compounds, dibenzothiophene (DBT) and 4,6-dimethyldibenzothiophene (DMDBT), dissolved in model solvents and HAGO. Aromatic compounds in the liquid decreased significantly the HDS rate of 4,6-DMDBT, especially for catalysts with high hydrogenation activity. H₂S displayed a similar inhibition effect with all catalysts. These effects were extremely pronounced in HAGO where the DBT HDS rate decreased by a factor of 10 while 4,6-DMDBT – of 20 relative to paraffinic solvent. The feasibility of using a highly active hydrogenation catalyst for deep HDS of HAGO is diminished by the strong impact of aromatics.     

Highly dispersed NiW/γ-Al2O3 catalyst prepared by hydrothermal deposition method

This article describes a novel hydrothermal deposition method for preparing highly dispersed NiW/γ-Al₂O₃ catalysts and demonstrates its advantages over the conventional impregnation method. Via the hydrothermal precipitation reactions between sodium tungstate and hydrochloric acid and between nickel nitrate and urea, respectively, the active species W and Ni were deposited on γ-Al₂O₃. In the hydrothermal deposition of WO₃, a surfactant hexadecyltrimethyl ammonium bromide (CTAB) was used to prevent the aggregation of WO₃. The characterization results obtained by means of X-ray photoelectron spectroscopy (XPS), N₂ adsorption and high-resolution transmission electron microscopy (HRTEM) measurements showed that compared with the catalyst prepared by the conventional impregnation method, the catalyst with the same metal contents prepared by the hydrothermal deposition had much higher W and Ni dispersion, higher specific surface area, larger pore volume, the significantly decreased slab length and slightly increased stacking degree of sulfided W species, leading to the significantly enhanced dibenzothiophene (DBT) hydrodesulfurization (HDS) activity. The DBT HDS assessment results also revealed that the catalyst containing 17.7 wt% WO₃ and 2.4 wt% NiO prepared by the hydrothermal deposition method had the similar DBT HDS activity as a commercial NiW/γ-Al₂O₃ catalyst containing 23 wt% WO₃ and 2.6 wt% NiO, resulting in the greatly decreased amount of active metals for achieving the same HDS activity.     

Dibenzothiophene hydrodesulfurization over MoP/SiO<Subscript>2</Subscript> catalyst prepared with sol-gel method

Silica-supported molybdenum phosphide, MoP/SiO₂ catalysts with different Mo weight loadings were prepared by temperature programmed reduction of the oxidic catalyst precursors, which were prepared via sol-gel technique using ethyl silicate-40 as silica source. Samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), BET surface area measurements, and their catalytic activity in hydrodesulfurization (HDS) was tested with dibenzothiophene (DBT) as model compound. XRD analysis revealed the amorphous nature of the catalyst up to 10 wt% Mo loading and the formation of crystalline MoP phase on amorphous silica support with higher Mo loading. BET surface area showed high surface area for catalysts prepared by sol-gel technique with lower Mo content, and the surface area decreased with increasing in Mo loading. The HDS results showed that prepared MoP/SiO₂ exhibited high HDS activity and stability toward the catalytic test. Among the series of catalysts prepared, MoP/SiO₂ containing 20 wt% Mo was found to be the most active catalyst. And the effects of reaction temperature and hydrogen pressure on conversion and product selectivity were investigated.     

Effect of Al and Ti content in HMS material on the catalytic activity of NiMo and CoMo hydrotreating catalysts in the HDS of DBT

Al- and Ti-containing HMS materials, with a Si/M (Me = Al(Ti)) molar ratio equal to 40, were used as supports for preparing NiMo and CoMo HDS catalysts. The supports and catalysts were characterized by N₂ adsorption–desorption (S_BET), X-ray diffraction (XRD), UV–vis diffuse reflectance (DRS UV–vis), temperature-programmed reduction (TPR) and Raman spectroscopy. The catalysts were tested in the hydrodesulphurization (HDS) reaction of dibenzothiophene (DBT). All supported NiMo and CoMo catalysts on Al-HMS and Ti-HMS substrates showed higher catalytic activity than their Me-free counterparts. We found two interesting correlations between the structure and chemical coordination of the supported oxide precursors and catalytic activity. The differences observed in catalyst performance are attributed to the structure and specific electronic properties of the supported active species. From our results, it appears possible to optimize the Al- and Ti-loading to maximize the HDS activity.     

HDS and deep HDS activity of CoMoS-mesostructured clay catalysts

The goal of this work is to identify more promising supports from synthetic clay materials to advance hydrotreating catalyst development. Silica sol can be used as the silicon-containing starting material when creating nanoporous layered silicate catalysts with a certain portion of unreacted sol particles incorporated into the final matrix. The resulting structure then has mesoporosity and a unique morphology. Hectorite-based clays have been prepared using different silica sols in order to ascertain the importance of sol characteristics on the final matrix. Several techniques have been applied to characterize the materials, including XRD, TGA, N₂ porosimetry, and TEM. For hydrodesulfurization (HDS), the conversion of dibenzothiophene (DBT) to biphenyl was examined at 400 °C using CoMoS-loaded mesostructured clay supports. No hydrogenation or hydrocracking was observed with any of the clay supports. The most active clay was derived from Ludox silica sol AS-30 with an activity of 65% DBT conversion and 100% selectivity to biphenyl (BP). For comparison, a reference commercial catalyst displayed 94% BP selectivity. For deep HDS, the conversion of 4,6-dimethyldibenzothiophene was tested at 325 and 350 °C. At 325 °C, conversions are 92% of commercial catalysts for a CoMoS-loaded mesostructured clay derived from Ludox AM-30 silica sol. A commercially available synthetic hectorite called laponite has very low activity, indicating that the unique morphology of the mesostructured clays is important. Hydrogenolysis vs. hydrogenation pathways are compared for the deep HDS reaction. HR-TEM of the most active deep HDS catalyst revealed a multilayered MoS₂ morphology.     

溶胶-凝胶法制备MoP/SiO_2催化剂及其加氢脱硫催化活性的研究

以正硅酸乙酯为硅源,以钼酸铵和磷酸二氢铵为钼源和磷源,采用溶胶-凝胶法,经干燥、焙烧处理后,程序升温还原制备得到二氧化硅负载磷化钼(MOP)催化剂,并以二苯并噻吩为模型化合物,对催化剂的加氢脱硫活性进行初步评价,考察了负载量、反应压力、反应温度等因素对催化活性的影响.结果表明,溶胶-凝胶法制备负载催化剂最佳磷化钼负载量为20%(质量分数);升高反应压力和温度均有利于提高二苯并噻吩的转化率,但降低了产物中联苯的含量.     

Performance of CoMoS catalysts supported on nanoporous carbon in the hydrodesulfurization of dibenzothiophene and 4,6-dimethyldibenzothiophene

A new type of nanoporous carbon with a large surface area and mesoporosity was prepared and used as a support for a hydrodesulfurization (HDS) catalyst. The overall activity of CoMoS catalysts for the HDS of dibenzothiophene (DBT) and 4,6-dimethyldibenzothiophene (4,6-DMDBT) is affected by the type of support used for preparing the catalyst and decreases in the order of CoMo/(nanoporous carbon)>CoMo/(activated carbon)>CoMo/Al₂O₃. The surface area of activated carbon is the largest among these three types of supports but is significantly lowered after metal loading during the preparation of the catalyst. On the other hand, the surface areas of the other two supports are largely preserved after metal loading. The intrinsic activity of the catalysts, estimated by dividing the overall HDS rate by the amount of NO adsorbed on the catalyst, shows a trend that is different from that for the overall activity, and follows the order of CoMo/(nanoporous carbon)≈CoMo/Al₂O₃>CoMo/(activated carbon). The low intrinsic activity of CoMo/(activated carbon) compared to that of the other two catalysts, particularly in the case of 4,6-DMDBT HDS, is obtained because the diffusion of reactants into the catalyst pores is significantly limited. This is not observed with other catalysts supported on nanoporous carbon and alumina. From the results of this study, we conclude that nanoporous carbon is a promising support for HDS catalysts, compared to conventional supports such as alumina and activated carbon, because it has a large surface area and a high mesoporosity, both of which are beneficial to the preparation of highly dispersed metal catalysts without significant pore blocking due to the dispersed metal particles.     

新型磷化钨加氢精制催化剂的研究

以γ-Al₂O₃为载体,磷酸氢二铵和偏钨酸铵为原料,通过化学浸渍法制备系列磷化钨催化剂。以噻吩加氢脱硫反应为探针,考察浸渍顺序、WP负载量、焙烧温度和还原温度等因素对磷化钨催化剂加氢性能的影响。研究表明,WP负载质量分数为30％的WP-1催化剂具有较高的噻吩加氢脱硫活性, P的加入在一定程度上能够改善催化剂加氢活性。     

Hydrodesulfurization of hindered dibenzothiophenes on bifunctional NiMo catalysts supported on zeolite–alumina composites

A series of NiMo catalysts supported on HNaY(x)–Al₂O₃ composites with different amounts of HNaY zeolite (x = 0, 5, 10, 20 and 100 wt.% of HNaY) was prepared and tested in the hydrodesulfurization (HDS) of dibenzothiophene (DBT) and 4,6-dimethyl-DBT (4,6-DMDBT). The catalysts were characterized by N₂ physisorption, X-ray diffraction (XRD), FT-IR spectroscopy of pyridine and nitrogen oxide adsorption (Py and NO-FT-IR), temperature-programmed reduction (TPR), scanning electron microscopy (SEM-EDX) and high-resolution transmission electron microscopy (HRTEM). It was found that the increase in the zeolite content causes changes in the acidic properties of the catalyst (number of acid sites) as well as in the characteristics of the deposited metallic species (location and dispersion). Different activity trends with the amount of the zeolite were found for the DBT and 4,6-DMDBT hydrodesulfurization on NiMo/HNaY-Al₂O₃ catalysts. As for the HDS of DBT the alumina-supported catalyst presents the highest activity. The incorporation of the zeolite causes an initial drop and then the recovery of activity with zeolite content. In contrast, for the 4,6-DMDBT the HDS activity always increases with zeolite content. These two different catalytic behaviors seem to be due to two opposite effects, which affect the contribution of the reaction routes available for the HDS of each reactant, these effects are: (i) the decrease of MoS₂ dispersion caused by the incorporation of zeolite to the catalyst and (ii) the increase of the proportion of Brönsted acid sites with zeolite content. The reaction product distribution indicates that both types of sites, coordinatively unsaturated sites (CUS) of the MoS₂ and zeolite Brönsted acid sites, participate in the 4,6-DMDBT and DBT transformations.     

Effect of Re loading on the structure, activity and selectivity of Re/C catalysts in hydrodenitrogenation and hydrodesulphurisation of gas oil

A series of Re-containing catalysts supported on activated carbon, with Re loading between 0.74 and 11.44 wt.% Re₂O₇, was prepared by wet impregnation and tested in the simultaneous hydrodesulphurisation (HDS) and hydrodenitrogenation (HDN) of a commercial gas oil. Textural analysis, XRD, X-ray photoelectron spectroscopy (XPS) and surface acidity techniques were used for physicochemical characterisation of the catalysts. Increase in the Re concentration resulted in a rise in the HDS and HDN activity due to the formation of a monolayer structure of Re and the higher surface acidity. At Re concentrations >2.47 wt.% Re₂O₇ (0.076 Re atoms nm⁻²) the reduction in the catalytic activity was related to the loss in specific surface area (BET) due to reduction in the microporosity of the carbon support. The magnitude of the catalytic effect was different for HDS and HDN, and depended strongly on the Re content and reaction temperature. The apparent activation energies were about 116–156 kJ mol⁻¹ for HDS and 24–30 kJ mol⁻¹ for HDN. This led to a marked increase in the HDN/HDS selectivity with decreasing temperature (values >3 at 325 °C), due to the large differences in the apparent activation energies of HDS and HDN found for all catalysts. A gradual increase in the HDN/HDS selectivity with increased Re loading was also found and related to the observed increase of catalyst acidity. The results are compared with those obtained for a series of Re/γ-Al₂O₃ catalysts.     

MCM-41-supported Co-Mo catalysts for deep hydrodesulfurization of light cycle oil

Light cycle oil (LCO), a by-product of the fluid catalytic cracking (FCC) process in a petroleum refinery, can be used as a blendstock for the production of diesel and jet fuels. Regulatory and operational issues result in need for new and more active catalysts for the deep hydrodesulfurization (HDS) of diesel feedstocks, such as LCO. This paper reports the activity of a mesoporous molecular sieve MCM-41-supported Co-Mo catalyst in comparison to a commercial γ-alumina (Al₂O₃)-supported Co-Mo catalyst for the desulfurization of a LCO with a sulfur content of 2.19 wt.%. The HDS of dibenzothiophene, 4-methyldibenzothiophene, and 4,6-dimethyldibenzothiophene—polyaromatic sulfur compounds present in LCO—and their relative reactivities in terms of conversion were examined as a function of time on stream in a fixed-bed flow reactor. The MCM-41-supported catalyst demonstrates consistently higher activity for the HDS of the refractory dibenzothiophenic sulfur compounds, particularly 4,6-dimethyldibenzothiophene. The presence of a large concentration of aromatics in LCO appears to inhibit the HDS of the substituted dibenzothiophenes.     

The functionalities of Pt/γ-Al2O3 catalysts in simultaneous HDS and HDA reactions

A Pt/γ-Al₂O₃ catalyst was tested in simultaneous hydrodesulfurization (HDS) of dibenzothiophene and hydrodearomatization (HDA) of naphthalene reactions. Samples of it were subjected to different pretreatments: reduction, reduction–sulfidation, sulfidation with pure H₂S and non-activation. The reduced catalyst presented the best performance, even comparable to that of Co(Ni)Mo catalysts. All catalyst samples were selective to the HDS reaction over HDA, and to the direct desulfurization pathway of dibenzothiophene HDS over the hydrogenation reaction pathway of HDS. The effect of H₂S partial pressure on the functionalities of the reduced Pt/γ-Al₂O₃ catalyst was studied. The results showed that an increase in H₂S partial pressure does not cause poisoning, but an inhibition effect, without changing the catalyst selectivity. Accordingly, the activity trends were ascribed to adsorption differences between the different reactive molecules over the same catalytic active site. TPR characterization along with a thermodynamics analysis showed that the active phase of reduced Pt/γ-Al₂O₃ is constituted by Pt⁰ particles. However, presulfidation of the catalyst leads to a mixture of PtS and Pt⁰ which has a negative effect on the catalytic performance without changing catalyst functionalities.     

Studies on recycling and utilization of spent catalysts: Preparation of active hydrodemetallization catalyst compositions from spent residue hydroprocessing catalysts

Spent catalysts form a major source of solid wastes in the petroleum refining industries. Due to environmental concerns, increasing emphasis has been placed on the development of recycling processes for the waste catalyst materials as much as possible. In the present study the potential reuse of spent catalysts in the preparation of active new catalysts for residual oil hydrotreating was examined. A series of catalysts were prepared by mixing and extruding spent residue hydroprocessing catalysts that contained C, V, Mo, Ni and Al₂O₃ with boehmite in different proportions. All prepared catalysts were characterized by chemical analysis and by surface area, pore volume, pore size and crushing strength measurements. The hydrodesulfurization (HDS) and hydrodemetallization (HDM) activities of the catalysts were evaluated by testing in a high pressure fixed-bed microreactor unit using Kuwait atmospheric residue as feed. A commercial HDM catalyst was also tested under similar operating conditions and their HDS and HDM activities were compared with that of the prepared catalysts. The results revealed that catalyst prepared with addition of up to 40 wt% spent catalyst to boehmite had fairly high surface area and pore volume together with large pores. The catalyst prepared by mixing and extruding about 40 wt% spent catalyst with boehmite was relatively more active for promoting HDM and HDS reactions than a reference commercial HDM catalyst. The formation of some kind of new active sites from the metals (V, Mo and Ni) present in the spent catalyst is suggested to be responsible for the high HDM activity of the prepared catalyst.     

制备条件对Ni2P/TiO2-Al2O3催化剂加氢脱硫性能的影响

采用溶胶-凝胶法制备了TiO₂-Al₂O₃复合载体, 以柠檬酸为络合剂, 浸渍法制备了负载型Ni₂P/TiO₂-Al₂O₃催化剂前体, 程序升温H₂还原法制备了Ni₂P/TiO₂-Al₂O₃催化剂, 并用 X 射线衍射(XRD)、N₂吸附比表面积(BET)测定技术对催化剂的结构和性质进行了表征, 考察了浸渍方法、Ni/P摩尔比、Ni₂P负载量对其进行的二苯并噻吩(DBT)加氢脱硫(HDS)性能的影响。结果表明, 当Ni/P比低于1:1时, 能得到单一的Ni₂P物相;当Ni/P比为2:1时, 开始出现Ni₃P物相。采用Ni/P比为1:1、Ni₂P负载量为30%、采用共浸渍方法制备的Ni₂P/TiO₂-Al₂O₃催化剂具有最好的活性, 在360℃、3.0MPa、氢油比500 (体积比)、液时体积空速2.0h^-1的条件下反应4h时, 二苯并噻吩转化率为99.5%。