FCC操作条件对汽油族组成及辛烷值的影响

通过对一种工业FCC催化剂在固定流化床上的评价 ,揭示了反应温度、剂油比和空速对汽油族组成及辛烷值影响的一些规律。研究发现 :随着反应温度的上升汽油中的总烷烃和异构烷烃含量下降 ,烯烃和芳烃含量上升 ;随着剂油比的增加 ,汽油中的总烷烃、异构烷烃和芳烃含量上升 ,烯烃含量下降 ;环烷烃、总烷烃、烯烃和芳烃的含量随着空速的变化出现相互交叉的现象 ;而汽油的辛烷值 (RON和MON)仅是转化率的函数 ,与达到同一转化率的操作条件无关     

多维气相色谱法测定汽油族组成

介绍了南化学工作站控制的Reformulyzer专用多维气相色谱分析系统。利用该系统，根据试样性质和分析要求选择相应的分析模式，对汽油中的正构烷烃、异构链烷烃，正构烯烃、异构烯烃、环烷烃、不饱和环烯烃、芳烃组分和含氧化合物进行了分析。     

催化裂化原料烃类组成对低碳烯烃生成的影响

采用固定流化床反应装置,以加氢减压蜡油HVGO-1、HVGO-2、HVGO-3、HVGO-3轻馏分和HVGO-3重馏分为原料,考察了催化裂化原料烃类组成对低碳烯烃生成的影响。结果表明：与密度、氢含量相近的HVGO-1相比,HVGO-2中环烷烃含量高、芳烃含量低是低碳烯烃产率高的原因;HVGO-3、HVGO-3轻馏分和HVGO-3重馏分反应得到相同规律,即链烷烃、环烷烃和烷基苯是生产低碳烯烃和汽油的优势组分,其中,链烷烃和环烷烃是生成低碳烯烃的高价值组分,烷基苯是多产汽油和轻芳烃(BTX)的高潜能组分;HVGO-3轻馏分和HVGO-3重馏分在相同反应条件下,由于HVGO-3轻馏分中环烷基苯含量高,促使低碳烯烃前身物及低碳烯烃发生氢转移副反应,影响低碳烯烃生成;催化裂化原料加氢预处理通过控制加氢深度,实现多环芳烃超深度加氢转化为环烷烃,避免因加氢深度不够导致环烷基苯的生成,有利于提高低碳烯烃产率。     

基于汽油分子组成的辛烷值模型开发

建立了一种基于Ghosh RON模型的改进了分子组成的预测汽油辛烷值的模型,能够通过调合组分分子组成和调合比例预测调合汽油产品的研究法辛烷值.该改进模型以汽油馏分的488种烃分子及含氧化合物为基础,并综合考虑了总芳烃与总烷烃、总烯烃、总环烷烃、含氧化合物4类组分之间的相互作用对辛烷值的影响.采用改进模型对直馏石脑油、重...     

窄馏分催化裂解汽油多产丙烯的研究

在实沸点蒸馏装置上将催化裂解汽油切割为不同沸点范围的窄馏分,在小型固定流化床装置上,对这些窄馏分汽油催化转化增产低碳烯烃进行了研究。试验结果表明：以初馏点~110℃的窄馏分汽油为原料时,反应温度为610℃时,丙烯产率最大,为25.49%;丙烯大部分来自原料中烯烃的裂解,少量的丙烯由正构烷烃、异构烷烃以及带有侧链的芳烃和环烷烃裂解得到;窄馏分汽油经芳烃抽提处理后丙烯产率增加。     

多维气相色谱法测定石脑油族组成

建立了一种采用具有多阀、多柱和吸附阱的多维气相色谱测定石脑油族组成的分析方法。通过5个阀对7根选择性不同的色谱柱进行准确切换控制,使样品分别进入不同的色谱柱中,分离出正构、异构烷烃,正构、异构烯烃,环烷烃,环烯烃和芳烃,然后利用程序升温,使各族组分再按碳数分离后进行定量分析。对标样的测定结果表明,组分质量分数可精确至0.01%,加标回收率为99.7%～108.6%,相对标准偏差为0.24%～1.40%。     

成品汽油组成及馏程与计算辛烷值的分布关系

根据汽油详细烃组成模拟计算了典型成品汽油不同馏分段的研究法辛烷值,获得了汽油馏分不同类型组分辛烷值和沸点分布的关系以及对样品辛烷值的贡献率。结果表明,不同类型组分辛烷值贡献率由大到小的顺序依次为芳烃、异构烷烃、烯烃、甲基叔丁基醚(MTBE)、环烷烃和正构烷烃。92#汽油辛烷值按照沸点的分布,呈现出两头大、中间小的特点。其中小于60℃的轻端馏分辛烷值的贡献主要来源于烯烃组分,大于120℃馏分段的辛烷值贡献主要来源于芳烃组分。90~120℃馏分有最低的辛烷值,60~90℃馏分有最低的辛烷值贡献率。加入一定量的烷基化汽油后,可以提高90~120℃馏分的辛烷值,改善汽油辛烷值的分布。     

采用BP神经网络预测石脑油裂解烯烃收率

在乙烯裂解工业装置的典型操作条件下,分别选取正构烷烃、异构烷烃、环烷烃、芳烃为裂解原料,考察了这些模型化合物的蒸汽裂解产物分布情况。结果表明,正构烷烃是优质的乙烯裂解原料,乙烯收率为36%~45%;异构烷烃的丙烯收率约为23%,明显高于正构烷烃;环烷烃裂解乙烯和丙烯收率较低,丁二烯收率则较高,为14%~15%;芳烃很难裂解生成烯烃。建立了包含2个隐层的级联前向BP神经网络,以模型化合物和石脑油样本裂解烯烃收率为依据对该神经网络进行训练,确定了模型参数,并对2种石脑油的裂解烯烃收率仿真数据与实验结果进行了对比。结果表明,二者的误差小于1个百分点,该模型可用于预测石脑油裂解的烯烃收率。     

利用捕集肼色谱技术分析裂解原料

采用通常的毛细管色谱方法 ,能够将石脑油中的各种烷烃、环烷烃、芳烷分离 ,但样品中若含有较多的烯烃 ,则分离不完全 ,无法准确测出。本文采用国际上新兴的捕集肼技术 ,用 3根捕集柱 ,将石脑油中的烷烃、烯烃、芳烃分别捕集 ,然后依次释放到分析柱进行分析 ,能得到准确可靠的分析结果。     

车用汽油储存安定性模型研究

随着国内外石油资源的日益匮乏,开展汽油、柴油等成品油的战略储备成为应对石油能源危机的重要手段。如何确定并提高油品的储存寿命,是战略储备油品的储存首先应当解决的问题。车用汽油由正构烷烃、异构烷烃、环烷烃、芳香烃、异构烯烃、正构烯烃、环状烯烃、双烯烃等烃化合物组成,其中不饱和烃平均占468％,见图1。     

汽油中氮化物的定性定量方法研究与应用

采用预富集技术提取汽油中的氮化物,结合气相色谱-质谱(GC-MS)定性,对照标准样品的色谱保留时间确定汽油中氮化物的形态。以气相色谱-氮化学发光检测法(GC-NCD)为分析手段,对汽油中氮化物进行定量分析,单组分化合物的检出限为0.6 mg/L。用该方法分析得出催化裂化汽油中氮化物的类型主要包括腈类、吡啶类、吡咯类、苯胺类。对市售车用汽油中氮化物的形态进行识别并定量分析,大部分常规车用汽油样品中氮化物的含量小于60 mg/L,其中几个车用汽油样品中苯胺类氮化物含量大于100 mg/L。     

页岩中矿物组分测定方法探讨

X-射线衍射(XRD)是测定页岩矿物组成的基本方法,其定量精度受到矿物种类、衍射能力、粒度和衍射峰重叠等多种因素影响。选择四川盆地黔浅1井页岩进行矿物组分测定,通过2种实验结果对比,找出提高页岩矿物组分定量精度的方法。方法1：全岩XRD直接测定与定量;方法2：经物相溶解、Stokes重力分离后,对不同粒级的矿物分别进行XRD测定与定量。结果显示,通过2种实验方法获得的碳酸盐类矿物的百分含量差别较大,反映了直接XRD定量方法在矿物组分含量测定中并不是完全可信的。经物相溶解及重力分离后进行XRD测试,可很大程度上提高测试精度,同时获得的页岩中矿物不同粒度的含量对认识页岩成岩过程及页岩性质较各单矿物含量更具有实际意义。     

Reducing Olefins Content of FCC Gasoline Using a NANO-HZSM-5 Catalyst

The study of reducing olefins properties on nano-HZSM-5 catalyst was investigated with a continuous fixed reactor using fraction of fluid catalytic cracking gasoline (75N120°C). The experimental results showed that nano-HZSM-5 catalyst has the best reducing olefins properties under the optimal conditions: temperature 430°C, pressure 0.3 MPa, and liquid hourly space velocity 1 h^-1, and the content of olefins in the feed stock decreased to 12.11% and dropped 31 percentage points. The yield of liquid product, the content of aromatics, and the content of isoalkane in liquid product are up to 84.98%, 39.58%, and 35.23% respectively.     

降烯烃技术在催化裂化装置的应用

介绍了最大量多产液化气和柴油(MGD)及最大量多产异构烷烃(MIP)技术在中国石油化工股份有限公司天津分公司炼油厂催化裂化装置的应用情况。结果表明,在应用MGD,MIP技术对催化裂化装置进行改造的同时,配合降烯烃催化剂的使用和原料的加氢处理,使催化裂化装置生产的汽油烯烃含量和硫含量明显下降,汽油质量可以满足欧Ⅲ标准要求。     

EFFECT OF ZSM-5 ADDITION ON PRODUCT DISTRIBUTION IN A HIGH SEVERITY FCC MODE

The high-severity fluid catalytic cracking (HS-FCC) process is a novel FCC process that enhances light olefins yield under high severity reaction conditions. The process has been investigated by using a small-scale FCC pilot plant (0.1 BPD) with a down-flow reactor. High severity reaction conditions are preferable for enhancing the production of light olefins by catalytic cracking of heavy oils. As another option for the light olefin production, adoption of ZSM-5 additive in conventional FCC units is well known. This presentation describes the effect of ZSM-5 additive on the catalytic cracking of vacuum gas oil under high severity reaction conditions, particularly focusing on the synergistic effect with the base catalyst. Three kinds of FCC catalysts with different activity were used as base catalysts. Although the employment of a ZSM-5 additive resulted in significant increase in the light olefins yield at the expense of gasoline in each catalyst system tested, the effectiveness was varied depending on the nature of the base catalysts. By choosing a suitable base cracking catalyst, more than 20 wt% of propylene yield was obtained at a one-pass conversion of fresh feed.     

EFFECT OF ZSM-5 ADDITION ON PRODUCT DISTRIBUTION IN A HIGH SEVERITY FCC MODE

The high-severity fluid catalytic cracking (HS-FCC) process is a novel FCC process that enhances light olefins yield under high severity reaction conditions. The process has been investigated by using a small-scale FCC pilot plant (0.1 BPD) with a down-flow reactor. High severity reaction conditions are preferable for enhancing the production of light olefins by catalytic cracking of heavy oils. As another option for the light olefin production, adoption of ZSM-5 additive in conventional FCC units is well known. This presentation describes the effect of ZSM-5 additive on the catalytic cracking of vacuum gas oil under high severity reaction conditions, particularly focusing on the synergistic effect with the base catalyst. Three kinds of FCC catalysts with different activity were used as base catalysts. Although the employment of a ZSM-5 additive resulted in significant increase in the light olefins yield at the expense of gasoline in each catalyst system tested, the effectiveness was varied depending on the nature of the base catalysts. By choosing a suitable base cracking catalyst, more than 20 wt% of propylene yield was obtained at a one-pass conversion of fresh feed.     

催化裂化轻循环油生产高辛烷值汽油技术LTAG的工业应用

福建联合石油化工有限公司在蜡油加氢处理和催化裂化装置上采用LTAG技术,以催化裂化轻循环油(LCO)和蜡油生产高辛烷值汽油。对LCO和蜡油混合加氢后得到的加氢LCO和加氢蜡油分别在催化裂化提升管反应器下部不同位置分层顺序进料方式(LTAG技术)与在催化裂化反应器下部混合进料方式的生产数据进行了系统的分析和总结。结果表明:与混合加氢油进料的常规方式进行对比,LTAG技术的LCO催化裂化表观转化率提高5.17百分点,表观裂化率提高7.87百分点,表观缩合率降低2.01百分点,稳定汽油中烯烃和芳烃的体积分数分别增加1.2百分点和2.0百分点,汽油辛烷值RON和MON分别提高1.4个单位和0.8个单位。LTAG技术是将LCO高效转化为高辛烷值汽油的重要手段。     

催化裂化汽油裂解制备低碳烯烃

在小型提升管催化裂化实验装置上研究了催化裂化(FCC)汽油催化裂解生产低碳烯烃的反应规律。实验结果表明,催化剂类型、反应温度、停留时间及水蒸气用量对乙烯、丙烯的产率均有显著的影响。高温、大剂油比、长停留时间及提高水蒸气用量都可促进汽油的裂解,增加低碳烯烃的产率。在实验室条件下,以ZC-7300为催化剂,多产低碳烯烃的最佳条件:反应温度580℃,停留时间1.6s左右,剂油质量比为11,水蒸气与汽油的质量比为0.20。对不同催化剂进行了对比实验得知,自制催化剂A的催化效果最好,汽油转化率达到40%以上,乙烯+丙烯的产率达到20%以上,焦炭和干气(不含乙烯)的产率不大于5%。     

MODELLING OF THE SOLVENT-DEOILING PROCESS OF WAXES BY CONTINUOUS THERMODYNAMICS

Industrial waxes as petroleum slack waxes are multicomponent mixtures of mainly paraffinic species. Usually, for application the oily components of the waxes are undesired. Therefore, separation processes are needed which, in some cases, base on a solvent-deoiling process. Modelling such a process is the aim of this paper. For this purpose the solid-liquid equilibrium of a wax-solvent system is considered. To take into account the polydispersity of the wax continuous thermodynamics is applied. We assume the wax to consist of n-alkanes and of non-n-alkanes including all the other types of paraffinic species. Corresponding to that, the composition of both types of alkanes is described by separate Gaussian distributions with respect to the number of carbon atoms. The model requires information about how the molar enthalpy and entropy of fusion for both kinds of alkanes depend on the number of carbon atoms. Restricting to the interesting range 20-50 of the number of carbon atoms we assume linear relations The lower values of the enthalpy and entropy of fusion for the non-n-alkanes compared to those of the n-alkanes are described by the so-called degree of isomerization and cyclization. This quantity correlates to the refraction index that is easy available. The model needs only one interaction parameter to fit. We show experimental and calculated results for three systems consisting of a slack wax and a solvent mixture of 1,2-dichloroethane and toluene. The model is able to describe reasonably the enrichment of n-alkanes for the deoiled wax and the opposite for the the oily phase.     

A New Catalyst for the Non-hydrogenation Reduction of Olefins

In this article, the preparation and application of a nonhydrogenation-reducing olefin catalyst were studied. The carrier of this catalyst was synthesized by γ-Al₂O₃ and SiO₂. It was found that the optimum molar ratio was 1:1 and the more suitable synthetic temperature was 80°C. The catalyst consisted of transition element Ni, W loading on the carrier that was self-made. Meanwhile, the properties of the catalyst were determined by an x-ray diffraction pattern (XRD), N₂-adsorption, and an FT-IR spectrophotometer. In order to study the performance of the catalyst, it was dried and calcined, and then it was reacted with the feed gasoline on the small fixed vector. The results showed that the content of olefins in fluid catalytic cracking (FCC) gasoline had been reduced from 51.0% to 25.6% when the reaction temperature was 170°C, the space velocity was 1.5 h^-1, and the reaction pressure was 2.5 MPa. The experimental results showed that the method of the catalytic preparation was simple and convenient, the activity of the catalyst was very high, and the regeneration and stability were also very good. The olefin content was reduced by more than 20% in FCC gasoline; the original octane number was not changed. Therefore the quality of the gasoline would meet the new gasoline standard (GB). The catalyst had very high industrial application value.