Performance Evaluation Studies of First- and Second-Stage Hydrocracking Catalysts Using Kuwait Vacuum Gas Oil Feedstocks

In a two-stage hydrocracking process, two types of catalyst are used to remove undesirable contaminants (such as S, N, hydrogenation of aromatic compounds, etc.) and convert the heavy feedstock to lighter products. In the present work, individual set of experiments were conducted to obtain information regarding activity and selectivity with emphasis on the evaluation of kinetic parameters of first- and second-stage commercial catalysts used in hydrocracking process. The performance tests were conducted in a down-flow fixed-bed hydrocracking pilot plant using a single reactor. The hydrotreating type A catalyst and hydrocracking type B catalyst were used individually with typical Kuwaiti refinery feedstocks, namely, hydrotreated vacuum gas oil (HVGO) and unconverted residual oil (UCRO), respectively. The order of reaction in this study shows first-order kinetics for HDS and HDN over CAT-A, and first-order hydrocracking conversion over CAT-B. For CAT-A the activation energies were found for HDS and HDN reactions at 22 and 27.3 kcal/gmole, while for CAT-B activation energies were 27.4 kcal/gmole.     

加氢裂化预处理催化剂功能分区研究

探究加氢裂化预处理过程中催化剂功能分区以及区域的反应规律,考察了在反应压力15.7 MPa、反应温度370℃、液态空速1.0 h-1、氢油体积比800的条件下,不同预处理催化剂功能区域脱氮率、脱硫率、芳烃转化率以及产品油的油品性质的差异.实验结果表明,原料油经过各反应区后油品性质不断提高,其中第一反应区影响最大,第一反...     

润滑油加氢催化剂的扩孔与酸改性

以改性氧化铝为载体,采用等体积浸渍法负载活性金属组分W和Ni,制备出润滑油加氢催化剂CAT-A,分别对其进行扩孔、酸改性处理,制得相应催化剂CAT-B,CAT-C。利用X射线粉末衍射、N2吸附-脱附、氨气程序升温脱附、扫描电子显微镜等分析手段,对所制备催化剂进行了表征;同时,以减四线馏分油为原料,在中试固定床加氢装置上,对催化剂进行了加氢性能评价。结果表明:扩孔处理使CAT-A催化剂上的可接触活性位点增加,有利于深度脱硫脱氮,酸改性则有利于硫化物在高温下的裂化脱除;在反应温度为390 ℃时,CAT-B催化剂加氢反应脱硫率、脱氮率分别为99.5%,99.7%,不低于280 ℃馏分收率（质量分数,下同）为94%, CAT-C催化剂的上述各值依次为99.6%,99.8%,90%。     

减压蜡油浆态床加氢工艺条件和动力学研究

对减压蜡油的浆态床加氢工艺条件进行了评价,并考察了减压蜡油的加氢脱硫和加氢脱氮动力学。研究结果表明,最佳的蜡油加氢工艺条件为反应温度360 oC、反应压力8 MPa、催化剂加入量（w）9 %、反应时间2 h左右。动力学研究结果表明：对于加氢脱硫反应,反应初期的表观活化能为100.44 kJ/mol;反应中期到末期,表观活化能为121.72 kJ/mol,这是由于不同类型的硫化物脱硫机理不同造成的;对于加氢脱氮反应,表观活化能为105.17 kJ/mol;在反应初期含氮化合物较难脱除,而在反应后期,烷基取代的二苯并噻吩类化合物为最难脱除的化合物。     

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。     

EFFECT OF Ni-Mo CATALYST MESOPORE DIAMETER ON CATALYTIC ACTIVITIES IN HYDROTREATING OF COAL LIQUID

ABSTRACT

A mixed 450^°C+ vacuum residue obtained from Austra-rian brown coal-derived oil with hydrogenated creosote oil was hydrogenated to elucidate the effect of catalyst mesopore diameter on the activities of Ni-Mo-γ-Al2O3 catalysts. Catalyst activities, especially for the heavy fraction in feedstock, were evaluated mainly by the conversion of 350^°C+ residue to 35O^°C ^? oil (HDC), hydrodesulfurization (HDS) and hydrodenitrogenation (HDN). These decreased in the order of HDS > HDN > HDC; whereas the deactivation rate during 50 hours on stream decreased in the order of HDC > HDN > HDS due to carbonaceous deposits on the catalyst. HDC, HDS and HDN rates per unit surface area of catalyst indicated that the HDS reaction was more strongly influenced by pore diffusion than the HDN and HDC reactions. The heavy ends in feedstock (such as asphaltenes) contained higher amounts of oxygen and nitrogen compounds. These polar compounds tended to be accumulated on the catalyst surface as the precursors for the formation of carbonaceous material deposits. The profile of carbon inside catalyst particle indicated that mesopore size of 22.6 nm might be satisfactory for reactant molecules to diffuse to the center of catalyst particle and access all of the active sites effectively.     

Hydrodesulfurization of Dibenzothiophenic Compounds in a Light Cycle Oil

Abstract

A hydrotreating study was conducted in a bench-scale hydroprocessing reactor, over a wide range of operating conditions of industrial interest, to look in detail at hydrodesulfurization (HDS), hydrodenitrogenation (HDN), and aromatics hydrogenation, and the interactions between these reactions. This article focuses on preliminary HDS results and some general findings. The feed used was a fluid catalytic cracking (FCC), light cycle oil (LCO) and the catalyst was a commercial NiMo/Al₂O₃ hydrotreating catalyst. The HDS results were analyzed by focusing on individual dibenzothiophenic sulfur species in the feedstock and products. Some of those species were positively identified while others were grouped into classes. It was observed that above 385°C, the assumption of irreversible pseudo-first-order reaction is not applicable for both total sulfur removal and sulfur removal of individual dibenzothiophenic species. All HDS reactions involving dibenzothiophenic structures reach a point where they are affected by hydrogenation/dehydrogenation equilibrium. Among all the 14 difficult-to-remove sulfur species identified in this work 4-methyldibenzothiophene (4-MDBT) has the highest HDS reactivity, while 4,6-dimethyldibenzothiophene (4,6-DMDBT) has the lowest HDS reactivity attributable to steric hindrance by methyl substitutes at 4 and 6 positions. It was also found that H₂S significantly reduces the reaction rates of HDS. However, this effect reaches a plateau as H₂S concentration in the gas phase increases. At low reactor temperature, HDS rates linearly increase with the increase in hydrogen partial pressure. At high temperature it reaches the limit of complete conversion.     

助剂对WP/γ-Al2O3催化剂性能的影响

 采用浸渍法和H₂气流中磷化还原法制备了一系列负载 30%WO₃和各种不同含量Ni、Co、V助剂的WP/γ-Al₂O₃, 并采用XRD、NH₃-TPD、XPS手段和高压微反装置对它们进行表征和催化活性评价,考察助剂Ni、Co和V对WP/γ-Al₂O₃催化剂物化性质和催化性能的影响. 结果表明, 加入适量的助剂Ni(3%～5%)、Co(5%～7%)和V(1%～3%)能够改善WP/γ-Al₂O₃催化剂表面上活性组分的分散性和增加WP/γ-Al₂O₃催化剂的比表面积. 助剂Ni和Co的加入使WP/γ-Al₂O₃催化剂表面上低价W物种数量增多.而助剂V的加入使WP/γ-Al₂O₃催化剂表面上低价W物种数量减少. 在高温(360℃)下咔唑加氢脱氮(HDN)反应中和低温(300℃)下的二苯并噻吩(DBT)加氢脱硫(HDS)反应中, WP/γ-Al₂O₃催化剂分别具有优良的HDN和HDS活性. 含有更高的DBT的HDS活性. 在较高温度(360℃)下DBT的HDS反应中, 含1%V的V-WP/γ-Al₂O₃催化剂的HDS活性高于WP/γ-Al₂O₃催化剂. 助剂Ni和Co明显促进了WP/γ-Al₂O₃催化剂在咔唑HDN反应中的活性, Ni助剂的助催化作用比Co更明显.含7%Ni的Ni-WP/γ-Al₂O₃催化剂和含5%Co的Co-WP/γ-Al₂O₃催化剂在300℃咔唑HDN反应中HDN活性很高. 加入1%的V可以提高WP/γ-Al₂O₃催化剂在咔唑HDN反应中尤其在360℃下咔唑HDN反应中的HDN活性.     

重质油窄馏分的HDS和HDN反应动力学特性

用破碎的工业加氢裂化催化剂Ｎｉ－Ｍｏ／Ａｌ２Ｏ３,在１００ｍｌ的高压反应釜内,对３种不同渣的超临界流体萃取分馏的窄馏分进行氢处理,建立了釜式反应器内渣油催化加氢脱硫和加氢脱氮反应的扩散－反应动力学模型,讨论了渣油窄馏分的扩散和加氢转化反应动力学特性。     

Hydrocracking of Vacuum Gas Oil: Conversion,Product Yields,and Product Quality over an Industrial Hydrocracking Catalyst System

Pilot plant experiments were conducted over an industrial hydrotreating/hydrocracking catalyst system using vacuum gas oil fraction obtained from a refinery crude distillation unit. Extensive pilot plant data were generated on the performance of industrial hydrocracking catalyst system with respect to conversion, product yields, and product quality at various operating conditions. The pilot plant experiments were carried out in a dual-reactor hydrotreating pilot plant system with downflow mode of operation. The temperature varied from 360 to 400°C and liquid hourly space velocity varied from 0.8 to 2.4 hr^?1, keeping a constant pressure of 170 kg/cm² and H₂/HC feed ratio of 845 L/L. The hydrocracked total liquid product was distilled in a true boiling point distillation unit to obtain yields and qualities of different fractions such as naphtha, kerosene, diesel, and unconverted oil. The effect of operating conditions on the performance of the hydrocracking catalyst system was discussed in detail. The kinetics of hydrocracking reaction was studied using a simple first-order reaction and a complex four-lump reaction system and the kinetic parameters were reported.     

Ni-Mo-Titania-Alumina Catalysts with USY Zeolite for Low Pressure Hydrodesulfurization and Hydrocracking

Abstract

Titania-alumina based catalysts were prepared and tested for hydrodesulfurization (HDS) and hydrocracking activity in the temperature range 300°C to 350°C in a fixed-bed reaction system using 4,6-dimethyldibenzothiophene (4,6-DMDBT) dissolved in n-hexadecane. Characterization results show that the metal-loaded titania-alumina possesses a high pore radius and pore volume but low surface area. The physical mixing with USY zeolite increased its surface area. The surface area was further increased upon mixing with nanoporous alumina. The total ammonia based acidity of the titania-alumina was lower than that of the ultra stable Y (USY) zeolite, but Ni-Mo loading was found to increase the acidity. The acidity of titania-alumina was further increased by mixing with nanoporous alumina and USY zeolite. All catalysts exhibited good HDS and hydrocracking activity for 4,6-DMDBT and n-hexadecane. The catalyst showing the highest HDS activity using 4,6-DMDBT was further tested and was found to have reasonable activity for both low- and high-sulfur vacuum gas oil feeds. This study demonstrated low-pressure HDS activity of the catalysts.     

催化裂化回炼油加氢精制反应规律研究

通过考察工艺条件对催化裂化回炼油加氢精制反应的影响,得到加氢精制油中不同烃类以及S、N质量分数随工艺条件的变化规律。结果表明：链烷烃及环烷烃质量分数随工艺条件变化不明显;增加氢油体积比、反应时间、氢分压均可促进HDA,HDS,HDN反应进行,但当超过最佳氢油体积比时,继续增加氢油体积比,HDA,HDS,HDN反应效果基本保持不变;提高反应温度有利于HDS反应的进行,而由于热力学平衡限制,HDA、HDN反应均存在一个最佳反应温度,且HDN反应的最佳反应温度较HDA反应高;在相同加氢精制条件下,不同结构的多环芳烃有不同的加氢饱和活性,迫位缩合型多环芳烃较渺位缩合型多环芳烃难加氢。     

中压加氢裂化装置催化剂再生及其反应性能评价

中海炼化惠州炼化分公司3.6 Mt/a煤柴油加氢裂化装置采用中国石化石油化工科学研究院开发的中压加氢改质MHUG技术及其配套的RN-10B精制剂和RT-5裂化剂,加工环烷基直馏煤柴油和催化裂化柴油的混合油,主要生产高芳烃潜含量石脑油、3号喷气燃料和满足国V排放标准的清洁柴油产品。在该装置第一周期连续稳定运转了5年6个月后停工检修,对催化剂进行器外再生,再生后催化剂的运转结果表明：经过长周期运转和再生后,RN-10B再生剂与新鲜剂的脱硫、脱氮活性相当;RT-5再生剂的活性和提高十六烷值能力与新鲜剂相当;RN-10B和RT-5催化剂活性稳定性良好,再生剂活性损失小,产品分布和产品性质达到或优于设计值,可满足长周期稳定生产需要。     

喹啉、吲哚对二苯并噻吩在NiMoS/γ-Al2O3上加氢脱硫反应的影响

 在固定床高压微反装置中考察了喹啉和吲哚对二苯并噻吩(DBT)在NiMoS/γ-Al₂O₃催化剂上加氢脱硫(HDS)反应活性及反应路径的影响.结果表明,喹啉和吲哚对DBT的加氢脱硫反应具有抑制作用. 少量的喹啉和吲哚即可强烈抑制DBT加氢脱硫反应的加氢路径; 而当含氮化合物加入量高时,才能较为显著地抑制DBT加氢脱硫反应的氢解路径. 在相同的条件下, 喹啉对加氢脱硫反应的抑制能力比吲哚强. 产物分析结果表明, 氮化物对DBT加氢脱硫反应的抑制作用与其分子结构和加氢脱氮反应中间产物的种类紧密相关.     

仪长渣油加氢处理反应规律的研究Ⅱ.新型催化剂及工艺条件的影响

针对仪长管输原油渣油(简称仪长渣油)的性质特点,开发了新型渣油加氢降残炭催化剂,并考察了加氢工艺条件对仪长渣油加氢处理反应的影响。通过选用镍钼型活性金属体系,改进载体的制备方法、浸渍工艺过程及添加助剂等开发了新型渣油加氢降残炭催化剂,使用该催化剂的级配体系具有更强的加氢饱和活性及杂原子脱除活性。在相同的操作条件下,与现工业装置应用的催化剂级配体系相比,使用新型加氢降残炭催化剂的级配体系可以使仪长渣油的残炭降低率提高3.3百分点、加氢脱氮率提高7.9百分点,有效提升仪长渣油的加氢生成油品质。在渣油加氢常规操作范围内,通过提高反应温度和氢分压、降低体积空速可以提高仪长渣油残炭降低率,促进加氢脱硫、加氢脱氮等反应的进行,有利于加氢生成油品质的提高。     

FF-46加氢裂化预处理催化剂的开发与应用

为了满足加氢裂化装置加工硫、氮等杂质含量高的原料的需要,中国石化抚顺石油化工研究院采用Mo、Ni为活性金属组分,通过合适的助剂降低载体表面的强酸量,使用络合技术负载活性金属,研制出新一代具有高加氢脱氮活性的加氢裂化预处理催化剂FF-46,并在中国石化镇海炼化分公司等单位的加氢裂化装置上实现工业应用。实验室小型装置评价结果表明,FF-46催化剂活性明显优于其它技术制备的催化剂,同时也优于工业参比剂;工业应用结果表明,FF-46催化剂的脱硫、脱氮活性高, 能够满足装置长周期运转的要求。     

FF-20加氢裂化预处理催化剂的研制

FF-20催化剂是FRIPP研制的新型高活性加氢裂化预处理催化剂。该催化剂以改性氧化铝为载体,采用一次浸渍法担载W、Mo、Ni金属组分,具有孔容大、比表面积大、孔分布集中、金属分布均匀等特点。催化剂性能评价试验结果表明：该催化剂用于加工处理国内外典型高硫蜡油,具有加氢脱硫脱氮活性高、芳烃加氢饱和能力强、稳定性好等特点,是一种性价比较高的馏分油加氢处理催化剂。     

催化裂化柴油一段加氢改质的新技术—MCI

Ｍ Ｃ Ｉ（最大限度提高十六烷值）工艺是一种改善劣质柴油馏分（如催化裂化柴油及其它高芳烃含量柴油）的加氢改质新工艺。 Ｍ Ｃ Ｉ工艺介于加氢精制和中压加氢改质（ Ｍ Ｐ Ｈ Ｇ）或中压加氢裂化（ Ｍ Ｐ Ｈ Ｃ）之间,它既具有加氢精制柴油馏分收率高的优点,又具有 Ｍ Ｐ Ｈ Ｇ 或 Ｍ Ｐ Ｈ Ｃ 对十六烷值提高幅度大的优点。 Ｍ Ｃ Ｉ工艺在接近加氢精制操作条件下利用一种新型催化剂进行加氢精制反应（如 Ｈ Ｄ Ｓ、 Ｈ Ｄ Ｎ 等）的同时达到提高柴油十六烷值的目的。此技术的关键是控制芳烃开环而不断链。一般情况下, Ｍ Ｃ Ｉ工艺能使柴油十六烷值提高 １０ 个单位以上,柴油收率高于９５％ 。     

国产加氢催化剂在锦西石化分公司加氢改质装置的首次应用

介绍了FF-36和FC-50加氢催化剂首次在锦西石化加氢改质装置的使用情况,对催化剂的硫化方法和钝化步骤进行了简要介绍,详细对比了国产催化剂与进口催化剂在操作条件、产品质量和对装置能耗影响三方面的数据。结果表明,国产催化剂相对于进口催化剂在操作条件上稍微苛刻一些,在脱硫率、脱氮率和柴油十六烷值上分别提高1.63百分点、2.6百分点和8.9个单位,而在能耗上相差不大。     

分子筛类型对四氢萘加氢裂化反应性能的影响

分别以改性Beta,Y,ZSM-5分子筛为载体,采用等体积浸渍法制备了Ni-Mo体系催化剂(分别命名为CAT-B,CAT-Y,CAT-Z),利用XRD、N_2吸附-脱附、NH_3-TPD、Py-FTIR、H2-TPR等手段对催化剂进行了表征。以四氢萘为模型化合物,在固定床连续加氢装置上考察了不同分子筛催化剂对四氢萘加氢裂化反应活性及产物选择性的影响。结果表明:CAT-B催化剂有较适宜的孔结构及比表面积,并且较CAT-Y和CAT-Z催化剂有较高的L酸量和B酸量,在金属组分与载体的相互作用力方面表现较弱,有利于金属组分的分散;催化剂对四氢萘加氢裂化反应转化率由高到低的顺序为CAT-BCAT-YCAT-Z,在四氢萘转化率相同时,催化剂CAT-B对BTX及加氢裂化产物的选择性最高,对缩合产物的选择性最低。