长链烷烃和双环烷烃混合原料加氢异构规律的研究——工艺条件的影响

将正十六烷和十氢萘按85∶15的质量比配成混合原料,以负载Pt的氢型TON结构分子筛作为催化剂,考察温度、压力、液时空速和氢/油体积比对于混合原料中链烷烃和环烷烃加氢异构转化活性和产物分布组成的影响。结果表明,混合原料中的十氢萘在异构体系中的反应活性很低,高温、低压下脱氢生成四氢萘,液时空速、氢/油体积比对十氢萘的转化几乎没有影响。对于混合原料中的正十六烷,低压有利于提高其转化率和异构烃的选择性,但相近转化率下,压力不改变单支链异构烃收率分布。低液时空速可以提高正构烷烃的转化率,但不改变产物分布。实验范围内,氢/油体积比的变化对正构烷烃的临氢转化几乎没有影响。     

氢分压对润滑油异构降凝反应的影响

采用石油化工科学研究院开发的RIW润滑油异构降凝催化剂，在固定床微反加氢装置上考察了不同氢分压下正十六烷的转化率和选择性，并以实际油品为原料。在中型加氢装置上进行降凝试验。结果表明，较低的反应温度、较低的氢分压有利于大分子正构烷烃在双功能催化剂上的异构化反应。从产品要求上看，尽管低压有利于生成低倾点的油品，但由于生成了较多的芳烃，影响润滑油基础油的安定性，很难满足API Ⅱ类油或API Ⅲ类油对芳烃含量小于10％的限定指标要求。因此在工业应用时，应该综合考虑异构降凝的反应压力，在相对合理的氢分压下操作。     

异构降凝催化剂反应性能的研究

开发了一种适用于长链正构烷烃的异构化催化剂,它含有一种具有TON晶体结构的新型沸石分子筛,对该剂的反应性能进行了研究,无论采用润滑油原料或加氢裂化尾油,该催化剂都具有高的异构降凝活性,即使在深度降凝的条件下,润滑油收率仍高达82％。基础油质量优良,可用来制取APIⅡ／或Ⅲ类的高档润滑油。     

加氢异构降凝催化剂RIW-2的开发及工业应用

针对以加氢裂化尾油、费-托合成油等多种原料生产优质润滑油基础油的要求，中国石化石油化工科学研究院开发了新一代润滑油异构降凝催化剂RIW-2。该催化剂具有良好的异构选择性、降凝活性、抗中毒性能和原料油适应性，其性能优于参比剂。考察了影响催化剂异构性能的多种工艺因素，结果表明：正构烷烃异构化存在一个最佳反应温度，同时随反应温度的提高，产物中多甲基异构烷烃含量增加；较低的氢分压有利于异构烷烃的生成，但会伴随着环烷烃的脱氢。该催化剂的工业应用结果表明，以加氢裂化尾油为原料，可以生产黏度指数大于120的API Ⅲ类润滑油基础油，收率大于70%。     

加氢处理光亮油中絮状物的组成分析

采用溶剂法分离并提纯了120BS加氢光亮油中的絮状物,测定了絮状物和脱絮状物光亮油的平均相对分子质量和模拟蒸馏曲线,采用气相色谱和核磁共振分析了絮状物的组成。结果表明：含絮状物120BS加氢光亮油中絮状物的质量分数为0.05%,絮状物对光亮油的性质基本没有影响,但对其外观影响较大;与脱絮状物光亮油相比,絮状物的平均相对分子质量高,相同馏出温度时馏出量小;絮状物含有质量分数为20.2%的正构烷烃,其余组分为具有一定异构化程度的异构烷烃和环烷烃;絮状物既含有凝点很高的高碳数正构烷烃、异构化程度较低的异构烷烃和环烷烃,又含有凝点略低、具有一定异构化程度的链烷烃和环烷烃。在宏观上,絮状物是微晶蜡和轻脱沥青油的蜡下油的混合物。     

长链正构烷烃的择形异构化催化剂

通过对长链正构烷烃择形异构化反应机理的分析，合成了一种具有TON结构的LKZ分子筛，改性后制备出贵金属催化剂WSI。在中型装置上以加氢裂化尾油和150SN润滑油为原料进行了异构化试验，该催化剂显示出良好的高的活性和异构化选择性，有明显的降凝效果，352℃以上馏分的收率较高。     

加氢异构化催化剂的研究——-加氢功能的影响

以ZSM 22分子筛为酸性组分,制备了不同分子筛含量、不同金属负载量以及不同金属种类的加氢异构催化剂。采用XRD、氢氧滴定、N2吸附、吡啶吸附和SEM等表征工具对所用分子筛以及制备的催化剂进行了详细的表征。以正癸烷为模型化合物,考察了制备的催化剂的烷烃异构转化活性和选择性,并将获得的反应结果与表征数据相关联。结果表明,对于长链烷烃加氢异构反应,当加氢功能不足时,长链烷烃加氢/脱氢反应为控制步骤;为了制备双功能平衡的加氢异构催化剂,Pd负载量要高于Pt,但当双功能平衡后2种催化剂的异构反应行为一致。对于长链烷烃加氢异构反应,加氢中心与酸性中心之间的距离不是影响催化剂异构选择性的关键因素。     

LKZ择形异构化分子筛的合成和工业应用

长链正构烷烃的异构化是改善柴油及润滑油基础油低温流动性的关键技术.由于异构烷烃被保留,既改善了油品低温性能,又提高了目的产品收率.分析了长链正构烷烃在双功能催化剂上加氢异构化反应机理,开展了由Si-Al两组分构成、具有TON结构的LKZ择形分子筛的合成研究.解决了分子筛合成的工业放大及工程问题,实现了大规模生产.以该分子筛为基质,配以氧化铝粘合剂及少量贵金属研发出了石蜡择形异构化催化剂.该剂的反应性能优越,稳定性良好,并在金陵石化低压加氢装置上实现了工业应用.     

低温费-托合成低温冷凝物加氢精制反应集总动力学

在200~300℃、液时空速1~40h-1、压力3MPa以及氢/油体积比300的条件下,采用Ni-W催化剂在固定床反应器中对低温费-托合成低温冷凝物(L-LC)加氢精制的集总动力学进行研究。将L-LC加氢精制反应体系划分为5个集总,构建了反应网络和动力学模型。依据实验数据计算动力学参数,得到其中正构烯烃加氢生成正构烷烃、正构烯烃异构化、异构烯烃加氢生成异构烷烃和异构烷烃生成正构烷烃反应的表观活化能分别为77.247、9.570、58.692、35.150kJ/mol。实验数据与该模型计算结果吻合,检验了该模型的准确性。利用模型讨论了烷烃异构化反应的平衡组成、中间产物的动力学规律和各集总组分反应速率的变化。     

C5、C6正构烷烃异构化反应的热力学分析

对C5、C6正构烷烃异构化反应进行了详细的热力学分析。通过计算得到了不同反应温度下的异构化反应的平衡常数、产物分布和转化率。讨论了异构化反应的温度、压力和氢／烃摩尔比对反应的平衡和产物分布的影响。     

THERMODYNAMIC FUNCTIONS OF THE SOLID-LIQUID TRANSITION OF HYDROCARBON MIXTURES

The dependences of the melting temperature and the enthalpy of fusion on the composition are the essential factors for modelling precipitation and solubility of solid hydrocarbons in crude oils and crude oil products. Long-chain iso-alkanes and cyclic alkanes must be considered besides of n-alkanes. Therefore a degree of isomerization and cyclization was defined using the refractive index and the carbon number. The melting temperatures and the enthalpies of fusion of different n-alkanes and fractions of crude oil were determined by differential scanning calorimetry. Both parameters can be correlated with the degree of isomerization and cyclization by a quadratic fuction.     

THERMODYNAMIC FUNCTIONS OF THE SOLID-LIQUID TRANSITION OF HYDROCARBON MIXTURES

ABSTRACT

The dependences of the melting temperature and the enthalpy of fusion on the composition are the essential factors for modelling precipitation and solubility of solid hydrocarbons in crude oils and crude oil products. Long-chain iso-alkanes and cyclic alkanes must be considered besides of n-alkanes. Therefore a degree of isomerization and cyclization was defined using the refractive index and the carbon number. The melting temperatures and the enthalpies of fusion of different n-alkanes and fractions of crude oil were determined by differential scanning calorimetry. Both parameters can be correlated with the degree of isomerization and cyclization by a quadratic fuction.     

润滑油异构脱蜡催化剂RIW-2的研究与开发

基于对烷烃临氢异构反应和润滑油异构脱蜡反应机理的认识，考察了分子筛性质对异构脱蜡催化剂性能的影响，合成了加氢异构活性和选择性较好的分子筛ZIP，并在此基础上开发了新型润滑油异构脱蜡催化剂RIW-2。评价结果表明：RIW-2具有较高的降凝活性和异构选择性，在产品达到相同倾点时，润滑油基础油收率与第一代异构脱蜡催化剂RIW-1相比明显提高；新型异构脱蜡催化剂RIW-2适用于各种含蜡原料的降凝过程，可以生产API Ⅲ+类高黏度指数基础油。     

用EVA复配物改善高含蜡原油低温流动性的研究

本文研究了采用化学处理剂改善南海高含蜡原油的低温流动性,结果表明,添加150ppm EVA复合化学处理剂,原油低温流动性得到明显改善,凝固点由32℃降至11.5℃,表观粘度降低86.9%,1;℃时屈服值降低98%。同时考察了添加温度,冷却速度以及化学处理剂的化学组成和结构对改善原油低温流动性的影响。根据南海高含蜡原油中蜡的组成和正构烷烃的碳数分布及其对不同结构的EVA的感受性,讨论了化学处理剂改善原油低温流动性的机理,指出,EVA中乙烯链长与原油中正构烷烃链长相近时才能形成共晶,起到改变原油中蜡的结晶形态的作用,达到降凝减粘效果。     

高选择性加氢异构降凝催化剂的研发及性能评价

针对直链烷烃异构反应过程的特点,开发了一种新加氢异构降凝催化剂。该催化剂采用新特制酸性分子筛以促进反应物分子接近反应位及异构中间产物快速脱离反应位。物化性质表征结果表明,与对比分子筛和催化剂相比,新分子筛和催化剂具有更大的孔体积和孔径以及更弱的酸性。以实际油品(加氢裂化尾油及费-托合成精制蜡)为原料的中试评价结果表明,与对比催化剂相比,采用新催化剂可获得更高的目标产品收率和黏度指数,且能适应不同的原料油。特别是加工费-托合成精制蜡时,新催化剂的活性和异构选择性优势更为明显。     

Normal Hexane Hydroisomerization Over an Alumina and Yttria Promoted Pt/SO4 2−/ZrO2 Catalyst

Sulfated zirconia was promoted with alumina and yttria in order to improve catalyst isomerization behaviors. The n-hexane hydroisomerization reaction was carried out in a continuous flow fixed-bed reactor for 80 h on stream to evaluate catalyst reaction stability. The catalyst was characterized by XRD, TGA, H₂-TPR, and NH₃-TPD technologies in order to investigate the crystalline structure, sulfur content, reduction behavior, and acidity of the catalyst. It was proved that the addition of alumina and yttria obviously increased the sulfur content on the fresh catalyst and also markedly stabilized the sulfur species on the used catalysts. Thus, the modified catalyst possessed the better stable activity and selectivity although the addition of promoter could not enhance the isomerization activity. The crystalline structure of sulfated zirconia, acidity, and sulfur content only showed a limited influence on the isomerization activity of the catalyst. This work would have potential use to prepare an ideal catalyst for a commercial alkane hydroisomerization unit.     

催化裂化油浆中较多链烷烃未裂化原因分析

针对催化裂化油浆中存在较多可裂化而未裂化的饱和烃这一问题,以正十二烷、丁基环己烷、四氢萘、十氢萘等为模型化合物,采用催化裂化实验与分子模拟相结合的方法,对催化裂化过程中链烷烃未充分裂化的原因进行了分析。在链烷烃单独催化裂化反应以及与其它结构烃分子进行混合催化裂化的过程中,链烷烃表现出不同的裂化活性,当链烷烃与强供氢性分子（四氢萘或十氢萘）混合时,链烷烃的裂化受到了明显抑制。在此基础上,结合分子模拟理论计算结果,提出了分子间负氢离子转移是导致催化裂化过程中链烷烃未充分裂化的主要原因之一。     

STUDIES ON LARGE CRUDE OIL ALKANES. II. ISOLATION AND CHARACTERIZATION OF AROMATIC WAXES AND WAXY ASPHALTENES.

ABSTRACT

Isolation of very large alkane components as described in the first paper within this series, fail in some cases. This work describes two non-routine isolation procedures applied to two different non-typical petroleum fractions. The first one comprises a chromatographic approach applied for the separation of alkanes from alkylaromatic compounds derived from paving asphalt waxes. The second separation procedure was developed for the isolation of alkane fractions associated with asphaltenes that precipitated during long crude oil storage periods, resulting in highly insoluble organic composites

In the first case, the isolated fractions were characterized by spectroscopic and chromatographic methods. The evidence showed that long chain naphtheno-aromatic molecules behave like waxy asphalt components, which interact by unusual mechanisms with solid sorbents. Their chromatographic behavior was found to be between typical alkanes and typical aromatics. This behavior is caused by the simultaneous presence of three functionalities

The second sample type was characterized by spectroscopic methods only. The results permitted to assess that the waxy composite from crude oil tank sediments precipitated selectively, including highly aromatic and long alkyl chain asphaltenes as well as very large n-alkanes.     

STUDIES ON LARGE CRUDE OIL ALKANES. II. ISOLATION AND CHARACTERIZATION OF AROMATIC WAXES AND WAXY ASPHALTENES.

Isolation of very large alkane components as described in the first paper within this series, fail in some cases. This work describes two non-routine isolation procedures applied to two different non-typical petroleum fractions. The first one comprises a chromatographic approach applied for the separation of alkanes from alkylaromatic compounds derived from paving asphalt waxes. The second separation procedure was developed for the isolation of alkane fractions associated with asphaltenes that precipitated during long crude oil storage periods, resulting in highly insoluble organic composites

In the first case, the isolated fractions were characterized by spectroscopic and chromatographic methods. The evidence showed that long chain naphtheno-aromatic molecules behave like waxy asphalt components, which interact by unusual mechanisms with solid sorbents. Their chromatographic behavior was found to be between typical alkanes and typical aromatics. This behavior is caused by the simultaneous presence of three functionalities

The second sample type was characterized by spectroscopic methods only. The results permitted to assess that the waxy composite from crude oil tank sediments precipitated selectively, including highly aromatic and long alkyl chain asphaltenes as well as very large n-alkanes.