Hydrocracking ofn-heptane on a sulfided NiMo-Y zeolite catalyst: effect of the sulfidation method

The activity and the selectivity of a bifunctional NiMo sulfides-Y zeolite catalyst forn-heptane hydrocracking depend very much on the sulfidation agent, namely hydrogen sulfide, or dimethyldisulfide in solution inn-heptane orn-decane. The presence of a hydrocarbon during the sulfidation lowers the acid activity of the catalyst because of coking of the zeolite acid sites, and also decreases the hydrogenating activity, due to a poorer sulfidation of the catalyst.     

MCM-41分子筛加氢裂化催化剂的研究

按水热法合成出介孔MCM-41分子筛，在不同的气氛下焙烧脱除有机模板剂。在固定床流动反应器上，与USY分子筛对比了正庚烷加氢裂化结果，发现MCM-41分子筛有较好的抗氮中毒能力，且其稳定时的加氢裂解活性比USY分子筛高。     

Zr改性Y分子筛中油型加氢裂化催化剂设计制备

采用等体积浸渍法对Y分子筛进行了Zr修饰改性,系统考察了不同用量Zr对改性Y分子筛的结构、催化剂的理化性质和加氢裂化反应性能的影响规律。通过XRD、NH₃-TPD、H₂-TPR和TEM等方法对改性分子筛和催化剂进行表征分析。结果表明：Zr改性降低了Y分子筛的酸量,随着改性Zr用量的增加,这种变化趋势不断增大。同时,Zr改性有效地削弱了分子筛催化剂中金属活性组分与载体间的作用,提高了W物种在催化剂表面的分散程度。加氢裂化反应结果表明：与Y分子筛催化剂相比,Zr改性Y分子筛催化剂的减压馏分油(VGO)转化率降低,中间馏分油选择性提高约20%,随着改性Zr用量的增加,VGO的转化率不断降低,中间馏分油选择性略有增加。     

二甲醚羰基化催化剂的烧炭再生

以水热合成的H-MOR分子筛催化剂,通过对二甲醚羰基化反应失活后催化剂进行再生,考察了不同再生气体、再生温度、O₂体积分数、烧炭升温速率等条件,烧炭后催化剂上二甲醚羰基化活性性能。TPO表征结果表明：反应后H-MOR分子筛上有两种不同性质的积炭。积炭催化剂在3%（体积） O₂/N₂气氛中,从室温以2℃·min^-1升温至320℃恒温一段时间,然后以相同速率升温至550℃进行烧炭,再生催化剂活性几乎完全恢复。NH₃-TPD和BET表征结果表明,再生催化剂活性得以恢复是因为优化了烧炭方案,分子筛表面积炭能够被烧除干净同时分子筛孔道不被破坏。     

异丁烷/丁烯烷基化分子筛催化剂的失活研究进展

分子筛催化剂在催化异丁烷/丁烯烷基化中具有良好的应用前景,但易失活,需频繁再生。系统总结分子筛催化剂在异丁烷/丁烯烷基化反应中的研究进展,认为烯烃低聚物覆盖活性位、堵塞分子筛孔道是催化剂失活的直接原因。论述了分子筛性能及烷基化反应条件对分子筛失活的影响,指出具有合适B酸强度和数量、易于丁烯低聚物脱附、利于扩散的分子筛催化剂是未来的研究方向。     

新型介孔分子筛加氢裂化催化剂的研制

研究了一种最大量生产中间馏分油的新型介孔分子筛加氢裂化催化剂,200 mL一段串联加氢装置评价结果表明,在控制原料＞350 ℃馏分油75%的高转化率条件下,C_⁺⁵液收98.6%,加氢裂化生成油中最大量柴油馏分收率为67.36%,中油选择性79.2%,能满足工业装置最大量生产中间馏分油的需要。重石脑油芳潜收率为41.16%,尾油BMCI值5.9,是理想的重整原料和蒸汽裂解制乙烯原料。     

加氢裂化催化剂的失活与激活

针对中石油吉林化学股份公司炼油厂加氢裂化装置在生产中遇到的加氢裂化催化剂失活问题， 分析其失活原因， 并介绍了在生产过程中 “激活” 催化剂的措施， 使中毒催化剂的活性逐渐得以恢复。     

四氢萘在含USY分子筛Mo－Ni加氢裂化催化剂上反应的研究

在国产３８２５型加氢裂化催化剂上，利用连续流动固定床微型反应装置，在４．５～８．５ＭＰａ和３２０～３８０℃条件下，测定了四氢萘加氢反应动力学数据，建立了四氢萘加氢裂化的反应网络和动力学模型。     

工业加氢裂化催化剂失活原因分析

采用200 m L加氢评价装置对一种中油型加氢裂化催化剂和其在工业装置运转4年后的再生后催化剂进行对比评价。结果表明,失活催化剂经再生后加氢裂化活性明显降低,反应温度比新鲜催化剂高5℃,生成油产品分布和主要性能都略变差。采用XRD、IR和ICP等手段对再生前后催化剂性能进行表征,分析探讨催化剂的失活原因,结果表明,加氢裂化催化剂经工业应用后,炭的沉积使其暂时性失活,而重金属沉积、金属活性组分聚集和分子筛结构烧结使催化剂部分活性永久丧失。     

茂名110万吨/年加氢裂化装置改造

全面总结了中石化茂名分公司加氢裂化装置改造为110万t／a后的工业生产和应用情况,介绍了该装置的改造原则、主要技术条件和工艺应用技术特点,讨论了装置改造后存在的若干问题,并提出了相关建议。     

Kinetics of and catalyst decay accompanying the gas phase rearrangement of cyclohexanone-oxime over a hy ultrastable zeolite

The kinetics of the rearrangement of cyclohexanone-oxime has been studied in a fixed bed, glass tubular reactor at atmospheric pressure and temperatures of 240, 270, 300 and 335°C, using ultrastable HY zeolite catalyst. Several kinetic models, including the Langmuir-Hinshelwood type, have been derived and the best statistical fit has been obtained with a pseudo-first order kinetic equation. The rate constants and activation energies for the formation of the products caprolactam, cyclohexanone and 5-cyanopent-l-ene have been calculated. Based on the evolution of the selectivity with temperature, and the I.R. spectra of the poisoned catalyst, different decay models have been deduced and discussed.     

改性MOY分子筛在降烯烃FCC催化剂中的应用

介绍了改性MOY分子筛性能和含MOY复合分子筛降低汽油烯烃含量催化剂的开发及应用。结果表明，MOY分子筛具有良好的氢转移选择性，是降烯烃催化剂较为理想的主活性组分。含MOY复合分子筛的FCC催化剂能有效地使FCC汽油中烯烃体积分数降低10%～12%，适用于生产优级清洁汽油。     

轻汽油醚化沸石催化剂反应性能

以催化裂化轻汽油为原料对开发的RZE-3沸石型醚化催化剂的反应性能进行了研究,并与树脂型催化剂进行对比。结果表明,沸石型醚化催化剂RZE-3的烯烃转化率、产物选择性与树脂型催化剂相当。沸石型催化剂由于具有优良的热稳定性,可反复再生,克服了树脂型催化剂不能再生、废弃催化剂会对环境造成污染等缺点。醚化原料中微量碱性氮化物在沸石型催化剂强L酸中心发生强吸附,是催化剂上胶质形成的主要途径和起点。沸石型醚化催化剂RZE-3的研发成功为清洁燃料洁净生产提供了可能。     

大庆1.2Mt/a加氢裂化装置的设计及标定

简要介绍了中国石油大庆石化分公司1.2Mt/a加氢裂化装置的工艺流程、主要技术特点及催化剂装填情况,对标定期间装置的原料性质、处理能力、操作参数、物料平衡、产品收率、装置能耗及设备运行状况进行分析,找出装置生产存在的问题.结果表明,装置运行平稳,催化剂性能良好,对原料适应性强,产品质量优良且分布合理,液体收率、加工损失率都在指标要求范围内,装置能耗达到国内先进水平,基本上达到了预期目标,说明装置设计和运行都比较成功.     

Supported BETA zeolite on preshaped β-SiC as clean Friedel-Crafts liquid-phase catalyst

Beta zeolite coated on a preshaped medium surface area silicon carbide carrier was prepared via an hydrothermal synthesis. ²⁷Al MAS NMR analysis revealed that all the aluminium was in a tetrahedral coordination and no trace of extraframework aluminium was observed. The Full Width at Half Maximum of the NMR peak was about 10 ppm, which indicates the presence of small zeolite crystals inside the sample. SEM observation has shown that zeolite homogeneousely coated the outer surface of the silicon carbide extrudate support with different size and shape and random orientation. The existence of a layer of silica and silicon oxycarbide on the surface of the support allows a strong anchoring of the coated zeolite. Thus, no zeolite loss was observed after sonication treatment for various durations. The as-prepared catalyst exhibits a high catalytic activity in the acylation of anisole by the anhydride acetic in batch mode configuration.     

C3液相选择加氢催化剂宏观动力学研究

在固定床积分反应器上研究了一种C3馏分液相选择加氢催化剂的宏观动力学。在不同的空速、温度、氢炔比条件下测定了反应的转化率和选择性，探讨了C3液相选择加氢的基本规律，并根据试验数据回归出了宏观动力学方程式。     

柴油加氢裂化装置加氢裂化催化剂失活分析

在某炼油厂柴油加氢裂化装置停工换剂时,取样分析加氢裂化催化剂。对所取裂化剂进行甲苯抽提、再生后,采用比表面积及孔径分析仪、碳硫分析仪(C-S)和X射线衍射仪(XRD)等手段进行检测。结果表明,失活裂化剂的比表面积、孔容等孔结构性能参数明显降低。在最优的再生条件下,再生裂化剂上的C含量降至0.360%,裂化剂的表面或其它位置未发现杂质的明显沉积。再生裂化剂的比表面积损失约21.5%,其中微孔比表面积的损失约占87.2%,孔容损失约17.4%。加氢裂化催化剂长期在高温等条件下反应,造成分子筛晶粒的烧结、团聚等是导致其比表面积等孔结构性能降低的主要原因。     

Kinetic modelling of methylcyclohexane ring-opening over a HZSM-5 zeolite catalyst

A kinetic model is proposed in order to quantify product distribution in the ring-opening (using high hydrogen concentration in the reaction medium) of methylcyclohexane (MCH) over a catalyst based on HZSM-5 zeolite. The model is based on a reaction scheme proposed by Cerqueira et al. for methylcyclohexane cracking at atmospheric pressure, which has been modified in order to include the effect of hydrogen over the individual reaction steps. The experimental results used for estimating the kinetic constant were obtained in a fixed bed isothermal reactor in a wide range of conditions, i.e. 250–450 °C; WHSV = 0.5–10.5 h⁻¹ (τ = 0.095–2 g_cat h g_MCH⁻¹); pressure = 5–80 bar; H₂/MCH molar flow ratio = 4–79; conversion = 0–100%. The kinetic model proposed can be regarded as a basis for the proposal of models for ring-opening reactions of more complex naphthenic feedstock from a prior hydrogenation step involving aromatic refinery streams of secondary interest.     

超声辅助制备酸碱双功能CaO/HMCM-22分子筛催化剂

采用超声浸渍法制备了一系列CaO改性的HMCM-22分子筛催化剂,使用XRD、N₂物理吸附-脱附、SEM、FT-IR、NH₃-TPD及CO₂-TPD等技术对催化剂物化性质进行了表征。结果发现在超声作用下经CaO改性后MCM-22分子筛的结构没有发生变化;超声空化作用降低了催化剂晶粒之间的团聚,促进了CaO在分子筛表面的分散,增加了可接触的催化活性位;随着CaO负载量的增加,催化剂上碱强度和碱量显著增加,而强酸含量明显减少,弱酸酸位有所增加。对催化剂在Knoevenagel缩合反应中的催化性能研究表明：与传统浸渍法相比,超声浸渍法所制备催化剂的催化活性明显较高,在优化的超声条件下反应2 h苯甲醛转化率即可达88.3%。催化剂CaO/HMCM-22的催化性能优于HMCM-22和CaO/NaMCM-22,对Knoevenagel缩合反应体现出明显的酸碱协同催化作用。超声法制备的催化剂重复使用性能显著提升,经过5次重复使用后苯甲醛转化率仍保持在65%以上。     

Kinetics of heptane reforming on Pt/L zeolite

The kinetics of heptane reforming over 0.64% Pt/KBaL have been measured over a wide range of conditions from 390 to 475 ° C, 0.05 to 1.00 atm heptane, and 0.2 to 25.0 atm hydrogen. Below about 6 atm H₂, the catalyst deactivates due to carbon fouling of the platinum particles. The reaction rate increases with hydrogen pressure under these conditions, presumably because this accelerates the rate of carbon hydrogenation off the metal surface. Above 6 atm H₂, no deactivation occurs. The activation energies and reaction orders in heptane and hydrogen at high H₂ pressure are: 39 kcal/mol, 0.7 and –1.9 for hydrogenolysis; 60 kcal/mol, 0.6 and –2.8 for isomerization; and 58 kcal/mol, 0.4 and –2.7 for dehydrocyclization. These kinetics are the same as those observed over platinum on nonacidic supports, and indicate that the reaction mechanism on Pt/KBaL is no different from that on monofunctional Pt catalysts.