双组分金属类型对四氢萘加氢裂化反应性能的影响

以Beta分子筛为载体,采用等体积浸渍法制备不同双组分金属类型(Ni-Mo、Ni-W和Co-Mo)加氢裂化催化剂,利用XRD、BET、NH3-TPD、Py-IR和H2-TPR等对催化剂进行表征。在固定床连续加氢反应器上考察催化剂对四氢萘加氢裂化性能的影响,结果表明,催化剂CAT-a(Ni-Mo/Beta)有较适宜的比表面积和孔体积,酸量和酸强度最大,四氢萘转化率和BTX选择性最高。以Ni-Mo/Beta催化剂为研究对象,考察不同金属负载量对催化剂物化性质及四氢萘反应性能的影响,结果表明,Beta分子筛载体上金属负载质量分数18%的催化剂最适宜四氢萘加氢裂化多产BTX类物质。     

重整预加氢催化剂国内外技术进展

催化重整预加氢催化剂主要是由载体和金属活性组分组成,最常用的预加氢催化剂的金属组分是Co-Mo、Ni-Mo、Ni-W体系.主要论述了催化重整预加氢催化剂的国内外技术进展,着重论述了国内重整预加氢催化剂的性质、特点及研发单位,提出了重整预加氢催化剂的发展方向,催化重整预加氢催化剂对直馏汽油要有良好的适应性,空速高,反应温...     

Upgrading Siberian (Russia) crude oil by hydrodesulfurization in a slurry reactor: A kinetic study

Hydrodesulfurization (HDS) of sour crude oil is an effective way to address the corrosion problems in refineries, and is an economic way to process sour crude oil in an existing refinery built for sweet oil. In the current study, the HDS of Siberian crude oil was carried out in a slurry reactor. The Co-Mo, Ni-Mo, and Ni-W catalysts supported on γ-Al₂O₃ were compared at the temperature of 340℃ and the pressure of 4.5 MPa. The HDS activity follows the order of Co-Mo > Ni-Mo > Ni-W at a high concentration of H₂S, and the difference between Co-Mo and Ni-Mo becomes insignificant at a low concentration of H₂S. The influence of reaction temperature 320-360℃ and reaction pressure 3-5.5 MPa was investigated, and both play a positive role in the HDS reaction. A kinetic model over Ni-Mo/Al₂O₃ in the slurry reactor was established. The activation energy is estimated as 60.34 kJ·mol^-1; the orders of sulfur components and hydrogen partial pressure are 1.43 and 1.30, respectively. The kinetic parameters are compared with those in a trickle-bed reactor, implying that the mass transfer is greatly enhanced in the slurry reactor. The back mixing effect is present in the slurry reactor and can be reduced by a multi-stage design, which would lead to higher reactor efficiency in industrial application.     

柴油加氢脱硫催化剂的选择

在连续流动固定床加氢装置上,考察Co-Mo型催化剂和Ni-W型催化剂在不同操作条件以及不同脱硫深度下的加氢脱硫反应性能。结果表明,两种催化剂对操作压力改变的敏感度不同;在不同的脱硫深度下,对不同的原料油也表现出不同的脱硫活性。     

Ni-W/SSY-Beta-Al_2O_3柴油加氢转化催化剂研究

采用SSY型分子筛、不同硅铝比Beta分子筛与大孔氢氧化铝干胶混捏制备SSY-Beta-Al_2O_3载体,等体积浸渍法制备Ni-W/SSY-Beta-Al_2O_3加氢转化催化剂,采用BET、Py-IR、XRD、NH_3-TPD对制备的催化剂及载体进行表征。在100 mL固定床加氢装置上,工业Ni-Mo型柴油加氢精制催化剂与Ni-W/SSY-Beta-Al_2O_3加氢转化催化剂级配装填,以劣质催化裂化柴油为原料,对加氢转化催化剂进行活性评价。结果表明,随着Beta分子筛硅铝比的增加,催化剂表面的L酸中心先减少后增多,B酸中心先增加后减少,催化剂的弱酸酸量先增多后减少,中强酸与强酸酸量变化不明显。在氢油体积比700∶1、反应压力8.0 MPa、精制段反应温度360℃,体积空速1.25 h^(-1),转化段反应温度400℃,体积空速1.35 h^(-1)的条件下,CYB-3催化剂加氢转化产品液相收率高达97.73%,汽油馏分收率63.72%,辛烷值91.66,柴油馏分收率33.69%,十六烷值比原料提高8.96,凝点小于-35℃。     

铁钴镍双组分氮化钼催化剂的制备和丙烷氨氧化性能的研究

以氢气和氮气的混合气体为氮化气体与铁钼、钴钼及镍钼双金属氧化物进行程序升温氮化反应合成了铁钼、钴钼及镍钼双金属氮化物催化剂。将铁钼、钴钼和镍钼氮化物分别用于催化丙烷氨氧化反应，研究结果表明，钴钼和镍钼双金属氮化物催化剂具有更高的催化活性和更高的丙烯腈选择性。     

重质芳烃油选择性加氢工艺研究

以油浆抽提得到的重质芳烃油为原料,通过选择性加氢工艺降低其中有害的稠环芳烃(PAHs)化合物,得到的精制油为橡胶用环保芳烃油。实验分别对反应温度、压力、时间以及一段、二段加氢工艺对PAHs转化率的影响进行了考察,同时运用BET及EDS对2种硫化态催化剂进行了表征,以考察催化剂的活性及选择性。结果表明,Ni-W/γ-Al2O3催化剂活性及选择性较Ni-Mo/γ-Al2O3高。实验证明:通过选择性加氢可大幅度降低重质芳烃油中PAHs质量分数,一段加氢采用Ni-W/γ-Al2O3催化剂,在反应温度280℃、压力8 MPa、时间6 h的条件下,原料PAHs转化率达到46.24%;二段加氢采用Ni-Mo/γ-Al2O3催化剂,在与一段相同的反应条件下,PAHs转化率达到32.94%。经2段加氢后,产物中PAHs质量分数由起始的58.13%降到21.05%,总转化率达到63.79%,液体总收率91.72%。     

Effect of cobalt (nickel) content on the catalytic performance of molybdenum carbides in dry-methane reforming

The dry-methane reforming (DMR) behavior of Co-Mo and Ni-Mo carbide catalysts has been studied in order to establish the effect of the cobalt or nickel content of molybdenum carbide DMR catalysts. The results indicate that incorporating cobalt into the Mo₂C structure at a Co/Mo ratio of 0.4, i.e. a Co_0.4Mo₁C_x catalyst, gives a DMR activity and stability that are markedly higher than those of Mo₂C catalysts. With respect to the Ni-Mo carbide catalysts, a Ni/Mo atom ratio of 0.2 (i.e. an Ni_0.2Mo₁C_x catalyst), gives the maximum synergistic interaction between Ni and Mo. However, higher molar ratios decrease the promoting effect and facilitate the phase separation of the promoter. These results are proved by X-ray diffraction, X-ray photoelectron spectroscopy, Fourier-transform infrared spectroscopy and N₂-adsorption studies, and are also reflected in the poor catalytic stability of both the Co-Mo and the Ni-Mo carbide catalysts.     

Optimization of the two-stage hydrotreatment for a coal liquid heavy distillate using some commercial catalysts at each stage

Catalytic up-grading of a coal liquid heavy distillate was examined using several commercial catalysts under variable conditions at hydrogen pressure of 150 atm (15.2 MPa). Some particular catalysts (Ni-Mo/Al₂O₃) exhibited much higher activities for denitrogenation in the two-stage hydrotreatment of 380°C for 3 h and 420°C for 3 h, although all Ni-Mo catalysts examined had similar activities for the cracking of paraffins in the distillate. Combinations of a Ni-Mo catalyst in the first stage (380°C for 3 h) with a silica-alumina or with a Co-Mo/Al₂O₃ in the second stage (420°C for 3 h) exhibited the highest activities for paraffin cracking (conversion 61%) or denitrogenation (96% removal), respectively. By optimization of the two-stage hydrotreatment, especially in terms of catalyst combination and reaction temperature, the total reaction time could be reduced to a practically acceptable one (3 h) by achieving satisfactory levels of paraffin cracking and denitrogenation.     

Ni-Mo/Y-β催化正辛烷加氢裂化的研究

以双微孔复合分子筛Y-β为载体，制备了双功能催化剂Ni-Mo/Y-β。表征发现， 浸渍后Ni-Mo/Y-β催化剂的比表面积、孔容、总酸量和结晶度均有所下降。并在固定床不锈钢反应器上考察了Ni-Mo/Y-β催化剂对正辛烷加氢裂化反应的催化性能，结果表明，在反应温度230 ℃、压力3.0 MPa、体积空速1.5 h-1和氢油体积比1 000∶1条件下，反应转化率为83.9%，裂解率82.28%，对异丁烷的选择性为37.49%。     

Hydrocracking of Vacuum Gasoil on NiMo/AAS-Al<Subscript>2</Subscript>O<Subscript>3</Subscript> Catalysts Prepared from Citric Acid: Effect of the Catalyst Heat Treatment Temperature

Ni-Mo bimetallic catalysts are prepared by impregnating a carrier containing amorphous aluminosilicate (AAS) and aluminum oxide using a solution with Ni, Mo, and citric acid. The temperature of the catalysts ranges from 120 to 550°С. The physicochemical properties of the catalysts are studied via XPS, TEM, and HCNS analysis, and they are tested in hydrocracking of vacuum gasoil. The particles of the sulfide active component (NiMoS phase) are localized predominantly on surfaces of aluminum oxide, and only some are on surfaces of AAS. When the temperature of catalyst calcination is raised, the average number of the layers in particles of the NiMoS phase grows as well, due to the removal of citric acid. This indicates strengthening of the interaction between the sulfide active component and aluminum oxide. The content of Ni-Mo massive sulfide particles also grows along with the temperature of calcination. The morphological characteristics of the sulfide active component affect the activity of the catalysts in hydrodesulfurization and hydrodenitrogenation, but not in hydrocracking. The optimum heat treatment temperature for NiMo/AAS-Al₂O₃ catalysts prepared with citric acid is 120°C. Recommendations are given for the heat treatment of catalysts under industrial conditions.     

Ni-W/SSY催化裂化生物正构烷烃制备航空燃料

以超稳SSY分子筛负载Ni-W制得加氢裂化催化剂,用于加氢裂化生物正构烷烃(C16、C18),得到以煤油和汽油为主的液体生物燃料,可以提高中油组分收率。通过氮气物理吸附,扫描电镜(SEM),X射线光电子能谱(XPS)等分析手段对催化剂进行了表征。在微型固定床连续加氢裂化反应器上,考察了反应条件对单程转化率和煤油/汽油质量比的影响规律。结果表明:255℃、1.0 MPa、质量空速为0.33 h-1、氢油比为4 000:1的反应条件下,单程转化率达到60%以上,煤油与汽油质量比超过2.0。Ni-W/SSY催化剂活性高,可以用于长链烷烃加氢裂化制备煤油组分为主的液体燃料。     

Zr改性ASA分子筛催化剂对煤焦油加氢脱硫脱氮性能的影响

采用硫酸锆为锆源,对无定型硅铝分子筛(ASA)进行改性,利用等体积浸渍法制备Ni-Mo/Zr-ASA加氢催化剂,在悬浮床反应器上考察Zr改性前后催化剂的煤焦油加氢脱硫脱氮性能。采用XRD和 TEM等对改性前后催化剂进行表征。结果表明,经过Zr改性后,催化剂Cat-Zr-ASA上的金属活性组分在载体表面高度分散,颗粒均匀,粒径较小。与未改性的催化剂Cat-ASA相比,Zr改性后的催化剂Cat-Zr-ASA上加氢产物S含量和N含量分别降低了56.4%和63.8%。     

浸渍方法对Ni-W/Y-ASA催化剂加氢裂化性能的影响

以高比表面积无定形硅铝（ASA）和改性Y型分子筛（USY）为原料制备催化剂载体,分别采用传统浸渍法、铝溶胶浸渍法、USY粉体浸渍法和ASA粉体浸渍法制备Ni-W/Y-ASA催化剂。采用氮气吸附-脱附、扫描电镜（SEM）、氨气程序升温脱附（NH₃-TPD）、吸附吡啶原位红外（Py-IR）和颗粒强度测定仪等表征手段,探究不同的浸渍方法对催化剂的织构性质、形貌、酸性以及机械强度的影响,并将制备的催化剂应用于正癸烷的加氢裂化反应。结果表明,采用ASA粉体浸渍方法,因较多地保留了Ni-W/Y-ASA催化剂中USY粉体上的B酸性位,使催化剂具有最多的B酸含量,增强了催化剂的酸性质,进而提高了催化剂在以正癸烷为模型化合物的加氢裂化反应中的裂化活性。     

Effect of pore size on bitumen hydrocracking over Al2O3-AlPO4 supported Ni-Mo catalysts

A study of co-precipitated aluminum oxide-aluminum phosphate (AAP) materials as supports of Ni-Mo heavy oil upgrading catalysts has been completed. Results of both short duration (8 h) and longer duration (up to 200 h) experiments at conditions relevant to the commercial H-Oil process are reported and compared with a commercial NiMo/Al₂O₃ catalyst. The initial activity of the Ni-Mo/AAP catalysts correlates with the catalyst average pore diameter which is determined by the P content of the AAP support. An optimum pore diameter of about 20 run exists for HDM whereas for HDS a pore diameter < 10 nm is desirable. After 100 h operation the HDM conversion of the best Ni-Mo/AAP catalyst was approximately 10 percentage points greater than for the commercial catalyst. The HDS and CCR conversions were comparable over the two catalysts. The difference in performance between the catalysts is attributed primarily to the smaller pore size of the Al₂O₃ support compared to the AAP support. The amount of coke deposited on the Ni-Mo/AAP catalyst was less than that on the commercial catalyst, presumably due to differences in pitch conversion levels.     

Catalytic (Mo) upgrading of Athabasca bitumen vacuum bottoms via two-step hydrocracking and enhancement of Mo-heavy oil interaction

Athabasca bitumen vacuum bottom (ABVB) was fractionated into 66.9% maltenes (n-pentane-solubles), 32.2% asphaltenes (n-pentane-insolubles), and 0.9% coke (toluene-insolubles). The maltenes were subsequently split into four sub-fractions: 5.6% saturates (MF1), 2.6% mono and diaromatics (MF2), 38.2% polyaromatics (MF3), and 20.3% polars (MF4). Yield maximization of the desirable light MF1 and MF2 sub-fractions was explored according to three catalytic (Mo) scenarios: (i) a one-step ABVB hydrocracking with light products recovery; (ii) two-step process consisting of ABVB hydrocracking followed by the hydrocracking of the maltenic MF3+MF4 sub-fractions; and (iii) one-step ABVB hydrocracking with specific pretreatment procedures to enhance contacting between Mo-based catalyst and the heavy oil. The products yield distribution was mapped according to a severity parameter combining temperature and time. Coke and gas formation increased with increased severity while asphaltenes and total maltenes decreased. For scenario (i), the optimum severity factor for the highest light products yield was 7.2. At this severity the ensemble of saturates, plus mono and diaromatics reached 32.7%. For scenario (ii), the optimum severity factors were 6.9 and 7.0 for the first and second hydrocracking steps, respectively, resulting in a total light products yield of 45.4%. In scenario (iii) where options such as increasing the catalyst concentration, removal of oil-borne coke before hydrocracking and ultrasonic mixing, the maximum MF1+MF2 yield reached 50.8% on raw ABVB weight basis at a severity factor of 7.2.     

Two-stage catalytic up-grading of vacuum residue of a Wandoan coal liquid

A successive two-stage hydrotreatment using a commercial Ni-Mo/Al₂O₃ catalyst (HDN-30) was applied to the vacuum residue of a Wandoan coal liquid to achieve high levels of hydrocracking, hydrodenitrogenation and hydrodeoxygenation. Two-stage hydrotreatment in 1-methylnaphthalene containing 20wt% fluoranthene as a solvent at solvent/coal liquid ratio of unity removed 83% (overall) of nitrogen and 90% (overall) of oxygen in the asphaltene (benzene-soluble fraction) at 380 °C for 3 h and at 420 °C for 3 under hydrogen pressure of 15 MPa and 14 MPa, respectively, while the single stage treatment at 420 °C for 3 h removed only 41% and 46%, respectively. The same two-stage treatment allowed the overall denitrogenation of 51% and the overall deoxygenation of 67% from a mixture of asphaltene and preasphaltene (THF-soluble fraction). Addition of the catalyst prior to the second stage reaction increased the removal of nitrogen and oxygen to 75 and 82%, respectively, indicating significant catalyst deactivation by the preasphaltene fraction in the first stage. Increasing the solvent/coal liquid ratio to 2 or addition of tetrahydrofluoranthene as a component of the solvent increased the removal of nitrogen and oxygen to 70 and 80%, respectively. Such two-stage hydrotreatment was also effective in refining the whole residue, allowing denitrogenations and deoxygenations of 68 and 75%, respectively using tetrahydrofluoranthene. The coke, unreacted coal and minerals in the residue may not cause acute catalyst deactivation. High dissolving ability of the reaction solvent is very effective to decrease catalyst deactivation by carbon deposition. The successive two-stage hydrotreatment also enhanced hydrocracking of polar and resin fractions in the residue into oils (conversion, 65%). The extensive hydrogenation of the former fractions in the first stage may allow more easy cracking and may suppress with the aid of solvents their irreversible adsorption on the catalyst which leads to their coking into the catalyst poisons.     

Influence of nitrogen compounds on deep hydrodesulfurization of 4,6-dimethyldibenzothiophene over Al2O3- and MCM-41-supported Co-Mo sulfide catalysts

The present work focuses on the effect of nitrogen compounds on the activity of MCM-41- and γ-Al₂O₃-supported Co-Mo catalysts for the deep hydrodesulfurization of 4,6-dimethyldibenzothiophene (4,6-DMDBT) in a fixed-bed flow reactor. Sulfur removal to the depths required by new specifications will require knowledge of the influence of non-sulfur diesel fuel components on deep hydrodesulfurization. The main objective of this paper is to examine the activity of hydrodesulfurization catalysts during and, most importantly, after exposure to basic and non-basic nitrogen. Quinoline (basic nitrogen) inhibits catalytic activity of both γ-Al₂O₃- and MCM-41-supported catalysts. It strongly inhibits hydrogenation and hydrogenolysis activity as evidenced by decreased selectivity for cyclohexylbenzene and biphenyl derivatives, respectively. To a certain extent, the long-term effects of quinoline are reversible. Carbazole (non-basic nitrogen) has little effect on the γ-Al₂O₃-supported Co-Mo catalyst but significantly inhibits the activity of the MCM-41-supported Co-Mo catalyst. The inhibition of the MCM-41-supported catalyst is reversible following removal of carbazole from the feedstock. Molecular modeling was also conducted to derive the bond order and electron charges of the nitrogen and sulfur compounds, which are helpful to understanding the experimental results.     

劣质催化柴油中多环芳烃选择加氢工艺评价

选取商品柴油加氢精制催化剂和催化柴油选择加氢裂化催化剂,采用N_2吸附-脱附、XRD、TPD、Py-IR等对催化剂进行表征,结果表明,选择加氢裂化催化剂较加氢精制催化剂具有更大的比表面积和孔容,具有更多的中强酸量和较少的弱酸量,并具有更多的B酸中心。以中石化青岛炼化公司生产的高密度、低十六烷值的FCC柴油为原料,对商品加氢精制催化剂和加氢精制/选择加氢裂化组合催化剂进行FCC柴油中多环芳烃选择加氢工艺条件的考察,结果表明,加氢精制催化剂适宜的反应条件为370℃、1.25 h~(-1)、8.0 Mpa,加氢精制/选择加氢裂化催化剂适宜的反应条件为350℃、1.25 h~(-1)、8.0 MPa,组合催化剂的多环芳烃选择加氢效果较好。     

Structural changes in catalytic hydroprocessing of syncrude coker gas oil

A method of Structural Group Analysis (SGA) was used to characterize feed and liquid products from catalytic hydroprocessing using a commercial Ni-Mo catalyst. Comparison of the structural profiles revealed significant changes in the concentration of various structural groups. SGA is a promising tool for investigating chemical changes in complex reacting systems.