渣油加氢脱金属催化剂初期失活的研究

以孤岛常压渣油和伊朗常压渣油为原料，在固定床试验装置上研究了两种加氢脱金属催化剂的初期失活，测定了不同运转时间催化剂上的积炭量。得到了催化剂加氢脱金属反应活性系数与运转时间的关联式。发现运转过程的前200h为初期失活阶段，此后进入稳定失活阶段。     

高硫渣油加氢反应动力学模型与失活模型的耦合应用

通过研究不同工艺条件(反应温度、压力和体积空速)对高硫渣油加氢处理反应的影响,构建了高硫渣油加氢脱硫、加氢脱氮、加氢脱残炭、加氢脱金属反应的动力学模型,并与颗粒活性区迁移模型(失活模型)进行耦合,从而利用耦合模型对渣油加氢装置的升温曲线、非常规操作及产品性质进行了模拟预测。模拟结果表明：经耦合模型模拟所得各反应转化率的预测值与试验值吻合度高;在加氢催化剂的整个评价周期内,随着加氢催化剂金属沉积比例增加,各反应转化率均呈现初期快速下降、中期缓慢下降、末期快速下降的规律;模拟产品性质恒定条件下加氢脱硫、加氢脱氮和加氢脱残炭反应的升温曲线,可以得到装置推荐的升温曲线。     

渣油加氢脱金属催化剂失活动力学模型的研究

以减压渣油为原料,在STRONG沸腾床渣油加氢装置上进行了试验,考察了催化剂活性变化的规律,根据催化剂失活的3个阶段,建立了催化剂失活模型并进行了模型验证。结果表明:运行初期反应温度对催化剂失活具有明显的加速作用,运行中期催化剂的活性主要取决于催化剂的金属沉积量;建立的模型预测值与实验值吻合得较好,表明该模型具有较好的准确性,可反映沸腾床渣油加氢催化剂失活的规律。     

柴油超深度加氢脱硫催化剂失活模型的建立

柴油超深度加氢脱硫催化剂的失活存在初期快速失活阶段和中期缓慢失活阶段,催化剂失活主要是由于积炭覆盖活性中心引起的。针对催化剂中期失活规律,将原料油性质与失活速率常数相关联,建立柴油超深度加氢脱硫催化剂失活模型,并对其进行验证。结果表明,所建立的失活模型可以较为准确地预测催化剂的失活速率,预测值与实测值的平均相对误差在5％以内。     

常压渣油加氢脱硫催化剂的研制及试生产

考察了常压渣油加氢脱硫催化剂制备方法对载体物化性质以及助剂、孔结构对催化性能的影响 ,试验结果表明 ,用优化方法制备的载体具有孔体积、比表面积大 ,孔分布集中的特点 ;引入的助剂明显改善了催化剂的反应性能 ;当孔分布主要集中在 5～ 1 0nm时催化剂对常压渣油加氢脱硫是合适的。小试定型的催化剂 (FZC 30 1 )在 2 0 0mL加氢小型装置上进行了 2 0 0 0h的稳定性试验 ,结果表明 ,FZC 30 1催化剂在处理中东高硫常压渣油时 ,反应性能优于国外同类催化剂的水平 ,并具有良好的活性稳定性。工业试生产的FZC 30 1催化剂重复了小试结果 ,为工业应用奠定了基础。     

H_2S和NH_3对渣油杂原子加氢脱除反应的影响

以中东高硫渣油为原料,在4种工艺条件下分别进行了一段加氢流程和两段加氢流程的渣油加氢试验,考察H2S和NH3对渣油杂原子加氢脱除反应的影响。结果表明:H2S和NH3在催化剂活性位上的竞争吸附抑制了渣油加氢脱硫反应,加氢反应气氛中较高含量的H2S和NH3不利于渣油加氢脱硫反应;由于H2S促进C—N键加氢分解反应,H2S对加氢脱氮有促进作用,反应气氛中较高含量的H2S有利于渣油加氢脱氮反应;H2S对加氢脱金属有促进作用,反应气氛中较高含量的H2S有利于渣油加氢脱金属反应。     

H2S和NH3对渣油杂原子加氢脱除反应的影响

以中东高硫渣油为原料,在4种工艺条件下分别进行了一段加氢流程和两段加氢流程的渣油加氢试验,考察H2S和NH3对渣油杂原子加氢脱除反应的影响。结果表明：H2S和NH3在催化剂活性位上的竞争吸附抑制了渣油加氢脱硫反应,加氢反应气氛中较高含量的H2S和NH3不利于渣油加氢脱硫反应;由于H2S促进C—N键加氢分解反应,H2S对加氢脱氮有促进作用,反应气氛中较高含量的H2S有利于渣油加氢脱氮反应;H2S对加氢脱金属有促进作用,反应气氛中较高含量的H2S有利于渣油加氢脱金属反应。     

渣油选择性加氢脱硫技术研究

以中东高硫渣油为原料,从催化剂开发、工艺条件优化、催化剂级配及活性稳定性考察等角度深入研究并开发了渣油选择性加氢脱硫技术。结果表明：新开发的渣油选择性加氢脱硫催化剂（包括专用脱金属剂和专用脱硫剂）的加氢脱硫活性显著高于常规渣油加氢催化剂（包括相应的常规脱金属剂和常规脱硫剂）;在加氢生成油硫含量相当的情况下,合适的氢分压、较低的体积空速、较高的氢油比以及较低的反应温度可以提高脱硫选择性;与常规渣油加氢脱硫技术相比,在脱硫率相当的情况下,新开发的渣油选择性加氢脱硫技术的反应温度低7 ℃,加氢生成油的残炭升高率为11.5%,加氢过程的氢耗降低率为7%～11%。     

高铁钙渣油沸腾床加氢技术研究

以仪长管输原油渣油为原料,用连续搅拌釜反应器模拟沸腾床考察了高铁钙渣油的裂化性能和杂质脱除性能,并研究了沸腾床加氢催化剂的初期失活情况。结果表明,反应温度是影响高铁钙渣油转化率和杂质脱除率的主要因素,积炭、金属硫化物的沉积造成的催化剂孔口堵塞失活是影响高铁钙渣油沸腾床加氢工艺经济性的主要因素,铁钙含量应该作为采用沸腾床加氢工艺还是固定床加氢工艺加工高铁钙渣油的判断标准。     

蜡油加氢脱硫催化剂RN-32V失活动力学研究

在中型固定床反应器上,以中国石化青岛炼油化工有限责任公司减压蜡油为原料,进行了加氢脱硫试验,并在此基础上建立了加氢脱硫反应动力学模型,同时考察了RN-32V催化剂活性随运转时间的变化情况,并建立了基于反应动力学的催化剂脱硫失活模型。对失活模型的验证结果表明,采用所建立的失活模型可较好地预测不同运行阶段产品硫含量及催化剂寿命,在指导工业装置运转方面有较好的参考价值。     

两类典型渣油原料加氢过程中脱金属催化剂运转初期失活研究

采用碳硫元素分析(CS)、催化剂氮含量分析(CAT-N)、热重 质谱联用分析(TG-MS)以及低温静态N₂物理吸附等技术手段,分别对在中型固定床渣油加氢实验装置上运转0(硫化后)、162、262、562 h后的卸出加氢脱金属催化剂进行表征,以研究高氮低硫类渣油加氢过程运转初期催化剂失活快的原因。结果表明：在相同催化剂级配体系和相同工艺条件下,与加工高硫低氮类沙特阿拉伯轻质原油的渣油原料(沙轻渣油)的脱金属催化剂相比,加工高氮低硫类仪长管输原油的渣油原料(仪长渣油)的脱金属催化剂上形成了更多的积炭,沉积的硫化物略少,而氮化物较多;加工仪长渣油的脱金属催化剂上形成了更多的高温型积炭,且相比加工沙轻渣油的脱金属催化剂上形成的高温型积炭更难氧化燃烧;积炭对加工仪长渣油的脱金属催化剂的孔结构性质影响更大,比表面积、孔体积均低于加工沙轻渣油的脱金属催化剂,大孔占比更低。     

固定床渣油加氢催化剂失活的原因分析及对策

固定床渣油加氢技术是重油改质的重要手段,是优化重油催化裂化装置原料的主要措施,而固定床渣油加氢装置催化剂的价格昂贵、使用周期短且不具再生使用性,因此探讨固定床渣油加氢催化剂失活的原因并采取相应的对策,对延长催化剂的使用周期有积极的意义。通过对固定床渣油加氢装置催化剂末期运行的现象、废旧催化剂化学组成等方面的分析,发现导致固定床渣油加氢装置催化剂失活的主要原因是积炭和金属沉积。同时分析催化剂级配装填的比例、催化剂硫化、原料油的性质和反应温度的分布等因素对固定床渣油加氢催化剂失活的影响,提出了采用抗积炭和容垢能力高的催化剂,进行合理的催化剂级配装填,控制好原料的性质,调整各床层反应温度的匹配分布和控制好催化剂开工条件等措施,可有效延长催化剂的使用寿命。     

An Investigation of the Deactivation Behavior of Industrial Mo/Al2O3 and Ni-Mo/Al2O3 Catalysts in Hydrotreating Kuwait Atmospheric Residue

The catalyst system for fixed-bed residue hydrotreating processes usually consists of different types of catalysts designed to promote hydrodemetallation (HDM), hydrodesulfurization (HDS) and hydrodenitrogenation (HDN) reactions to desired levels. Overall catalyst life is determined by the performance of the individual catalysts in the different reactors. Therefore, information about the activity, stability, selectivity, and deactivation behavior of the individual catalyst is highly desirable to design improved catalysts that can prolong catalyst life, increase stream efficiency, and improve process economics. In the present work, residue hydrotreating experiments were conducted on two types of industrial hydrotreating catalysts, namely Mo/Al₂O₃ and Ni-Mo/Al₂O₃, that have been used as HDM and HDS catalysts, respectively, in an industrial ARDS process. The primary objective of the study was to compare the deactivation behavior of both types of catalyst. The characterization of the used catalysts by elemental analysis, surface area, pore volume, and pore size measurements along with TPO-MS, ¹³C NMR, and electron microprobe analysis showed significant differences in the nature of the coke and metal deposits on the two types of catalysts. The role of initial coking, the relative importance of the coke, and metal depositions on the deactivation of the two types of catalyst are discussed.     

An Investigation of the Deactivation Behavior of Industrial Mo/Al2O3 and Ni-Mo/Al2O3 Catalysts in Hydrotreating Kuwait Atmospheric Residue

Abstract

The catalyst system for fixed-bed residue hydrotreating processes usually consists of different types of catalysts designed to promote hydrodemetallation (HDM), hydrodesulfurization (HDS) and hydrodenitrogenation (HDN) reactions to desired levels. Overall catalyst life is determined by the performance of the individual catalysts in the different reactors. Therefore, information about the activity, stability, selectivity, and deactivation behavior of the individual catalyst is highly desirable to design improved catalysts that can prolong catalyst life, increase stream efficiency, and improve process economics. In the present work, residue hydrotreating experiments were conducted on two types of industrial hydrotreating catalysts, namely Mo/Al₂O₃ and Ni-Mo/Al₂O₃, that have been used as HDM and HDS catalysts, respectively, in an industrial ARDS process. The primary objective of the study was to compare the deactivation behavior of both types of catalyst. The characterization of the used catalysts by elemental analysis, surface area, pore volume, and pore size measurements along with TPO-MS, ¹³C NMR, and electron microprobe analysis showed significant differences in the nature of the coke and metal deposits on the two types of catalysts. The role of initial coking, the relative importance of the coke, and metal depositions on the deactivation of the two types of catalyst are discussed.     

延长渣油加氢装置运转周期的RHT技术及其工业应用

通过研制抗积炭和脱金属、容金属能力高的催化剂,进行合理的级配装填,并控制反应器压差过早上升和热点过早出现,中国石化石油化工科学研究院开发了能显著延长操作周期的渣油加氢处理(RHT)技术及RHT系列渣油加氢催化剂。在多套渣油加氢装置的工业应用中, RHT系列催化剂不仅表现出良好的活性,更表现出了优异的活性稳定性,延长渣油加氢装置的运转周期,为炼油厂创造了巨大的经济效益。     

超细负载型Ni-Mo/Al2O3催化剂在渣油加氢裂化中的应用

针对渣油固定床加氢工艺催化剂易结焦失活以及悬浮床加氢工艺催化剂活性偏低的问题,将能悬浮在渣油中的超细负载型催化剂(Ni-Mo/Al2O3)应用于渣油的加氢裂化反应,并在高压釜中考察了反应条件对新疆减压渣油(XJVR)转化率的影响,其中催化剂添加量(质量分数)的考察范围为1%～10%、反应温度为410～450℃、反应时间为0.5～2.5 h、氢气初始压力为5～9 MPa。结果表明,催化剂的添加量对渣油、沥青质以及残炭转化率的影响都很小,但增加催化剂添加量能明显地促进硫的转化,即在此催化体系下,渣油的裂化反应以热反应为主,而加氢脱硫反应则由催化剂的活性中心所决定;反应温度对渣油、残炭、沥青质以及硫的转化率的影响较大,随着反应温度的提高,渣油、残炭、沥青质以及硫的转化率都呈上升的趋势,且前三者的上升趋势更为显著;延长反应时间对反应转化率的影响与提高反应温度所得到的结果类似;当氢气严重过量时,再提高氢气压力对硫转化率没有影响,但可在一定程度上促进残炭和沥青质的加氢反应。     

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。     

EVALUATION OF FEEDSTOCKS FOR DEVELOPMENT OF HYDROCRACKING CATALYSTS FOR HEAVY OIL

A number of feedstocks namely Arab Light atmospheric residue (ALAR), Arab Heavy atmospheric residue (AHAR), vacuum gas oil (VGO) and hydrotreated vacuum gas oil (HT-VGO), were evaluated for their physical and chemical characteristics. The characterization results of the feedstocks show the complex nature and composition of both residues and gas oils. The distillation results showed that about 50 weight percent of Arab Light crude consists of atmospheric residue. The elemental analysis of the ALAR showed that high amount of carbon, sulfur and nitrogen is present along with heavy metals such as nickel and vanadium. In case of Arab Heavy crude oil, the atmospheric residue is even higher, that is 57 percent and contains higher amount of metals along with more carbon, sulfur and nitrogen contents. The determination of hydrocarbon types by HPLC exhibited that ALAR contains higher amount of saturates compared to AHAR but less amount of aromatics, polars and asphaltenes. ALAR was found to have 55% saturates, 27% aromatics, 12% polars and 6% asphaltenes while AHAR has 30% saturates, 42% aromatics, 18% polars and 10% asphaltenes. Molecular weight determination indicated that the molecular weight of ALAR was determined to be 511 compared to 595 for AHAR. ALAR being lighter, showed 54% distillation at 547°C while AHAR exhibited 45% distillation at 543°C. VGO was found to have 13% saturates, 68% aromatics and 19% polars while HT-VGO had 29% saturates, 63% aromatics and 8% polars. VGO was found to have high IBP and FBP compared to HT-VGO. On the basis of the characterization data, VGO was selected to be use with catalysts containing high pore size supports such as alumina, silica alumina and clay while HT-VGO was selected as feedstock for performance evaluation of zeolite based catalysts. ALAR and AHAR will be utilized in the later stages of the catalysts development work.