基于分子管理的13X分子筛吸附分离石脑油中的芳烃

在5A分子筛吸附分离石脑油中正构烷烃的基础上,采用固定床吸附器对比考察了13X分子筛对石脑油及其脱正构油中芳烃的吸附分离性能。实验结果表明,13X分子筛吸附分离石脑油中芳烃的优化工艺条件为:吸附温度290℃,进料气态空速75 h~(-1),吸附时间30 min,N_2脱附气态空速150 h~(-1)时的适宜脱附时间为75 min;石脑油经5A分子筛和13X分子筛吸附分离后,正构烷烃和芳烃含量(w)分别由31.9%和12.8%降低到0.4%和1.7%,异构烷烃和环烷烃含量(w)分别由34.7%和20.6%增加到62.1%和35.8%;5A分子筛脱附油中正构烷烃含量达到94.8%(w),可作为优质的裂解制乙烯原料;13X分子筛脱附油中芳烃含量为85.1%(w),可直接作为芳烃抽提的原料。     

梯度冷却尿素络合法分离费-托合成油中正构烷烃

以费-托合成馏分油为原料,采用梯度冷却尿素络合法对正构烷烃进行分离,生产煤基费-托合成液体石蜡,考察了降温速率和络合反应条件对正构烷烃分离效果的影响,并采用气相色谱-质谱联用仪、详细烃组成分析等方法对产物的组成进行分析,结果表明:当反应体系的温度由45℃以1℃/min的速率下降至25℃,尿素异丙醇水溶液与油的质量比为1...     

分离石脑油中单甲基异构烷烃吸附剂的制备及吸附性能研究

采用水热合成法制备用于分离石脑油中单甲基异构烷烃的ZSM-5分子筛吸附剂,以2-甲基戊烷/环己烷溶液为吸附体系,考察不同合成条件对分子筛吸附性能的影响。结果表明：在硅铝比为80、25 ℃、陈化时间为36 h、晶化时间为48 h的条件下,以正丁胺为模板剂,合成ZSM-5分子筛吸附剂对2-甲基戊烷吸附量为2.39 g/(100 g),比参比ZSM-5分子筛对2-甲基戊烷吸附量高约20%;采用合成ZSM-5分子筛对石脑油进行吸附分离,吸附组分中正构烷烃和单甲基异构烷烃质量分数为97.47%;吸余油的芳烃潜含量从23.19%提高到34.21%;通过合成ZSM-5分子筛吸附分离可以将石脑油中质量分数约为30%的正构烷烃和约12%的单甲基异构烷烃分离出来。     

石脑油中正构烷烃在5A分子筛上液相吸附动力学特性

设计双阀门液相吸附动力学测定装置测定正构烷烃在5A分子筛上的液相吸附动力学数据,分别考察吸附温度、正构烷烃碳数以及正构烷烃初始浓度对石脑油中正构烷烃在5A分子筛上吸附速率的影响。结果表明：随着吸附温度和正构烷烃初始浓度的增加,正构烷烃在分子筛上的吸附速率变快;而随着正构烷烃碳数的变化,正构烷烃在分子筛上的吸附速率变化不明显。分别以异辛烷、甲基环己烷和甲苯为溶剂考察石脑油中不同非正构烷烃组分对正构烷烃在5A分子筛上吸附特性的影响。结果表明,石脑油中不同非正构烷烃类对正构烷烃在5A分子筛上吸附速率影响从大到小的顺序为：芳香烃类>环烷烃类>异构烃类。采用阿仑尼乌斯公式对实验数据拟合结果表明,以芳香烃化合物为溶剂时正构烷烃在5A分子筛上的扩散阻力最大。     

络合法分离富集重石脑油中正构烷烃

从石脑油中分离或富集正构烷烃可以降低催化重整和乙烯生产的成本,优化原料组成,提高生产效率。使用尿素和硫脲为络合剂、质量分数95%的乙醇为活化剂,将正辛烷、异辛烷、甲基环己烷、甲苯按不同比例混合作为模拟石脑油进行络合富集,考察络合相产品中各组分含量及正辛烷收率。结果表明：使用尿素/硫脲络合富集重石脑油中的正构烷烃是可行的,络合试验最佳反应条件为：质量分数为95%的乙醇活化剂用量80 mL,模拟石脑油用量60 mL,尿素/硫脲质量比50/21,络合温度-10℃,时间1 h;少量芳烃会对正辛烷分离效果产生一定的负面影响,工业上可以先用萃取法分离芳烃,然后再进行络合分离。     

分离石脑油馏分组成优化乙烯原料

为了改进乙烯原料,提高乙烯收率,分别选取正构烷烃、异构烷烃、环烷烃和芳烃为裂解原料,考察模型化合物的蒸汽裂解产物分布,并分别采用分子筛吸附分离和溶剂萃取两种工艺,提出了可以适应三种目的烯烃产品不同比例需求的裂解制乙烯原料分子生产路线。在典型的裂解工艺条件下石脑油中的正构烷烃对裂解产物中乙烯的贡献最大,异构烷烃是产生丙烯的主要来源,而环烷烃主要生成丁二烯,芳烃很难裂解生成烯烃。通过吸附分离工艺富集石脑油中的正构烷烃,富含正构烷烃的脱附油蒸汽裂解制乙烯收率与不富集石脑油原料相比可提高13%。通过溶剂萃取将芳烃和环烷烃从石脑油中萃出,萃余油蒸汽裂解制乙烯和丙烯收率与未萃取石脑油原料相比分别提高3.0%和1.5%。分子筛吸附分离和溶剂萃取工艺相结合可以显著提高裂解烯烃收率。     

烃分子结构对其催化裂解反应性能的影响

采用脉冲微型反应器和小型固定流化床催化裂解装置,研究了直馏石脑油中不同结构烃分子的裂解反应性能,考察了链烷烃与环烷烃的相互作用,以及催化材料对烃分子裂解性能的影响。结果表明：随着烷烃分子支链度的增加,C8烷烃的反应性能降低,丙烯选择性提高;链烷烃和具有烷基侧链的环烷烃是丙烯的主要来源,双环环烷烃对丙烯也有部分贡献,而芳香烃不易生成低碳烯烃;环烷烃的竞争吸附抑制了链烷烃的转化,而链烷烃在催化裂解过程中生成的碳正离子或烯烃提高了环烷烃的反应性能;与Beta分子筛相比,ZRP分子筛具有较狭窄孔道和较多的Brønsted酸中心,有利于正辛烷的质子化裂解,裂解产物中乙烯和丙烯产率高。     

烃分子在H-FAU分子筛上吸附模拟研究

利用量子力学与分子力学结合的方法研究C_(14),C_(22),C_(30)的直链2-烯烃、芳烃、直链烷烃、环烷烃在H-FAU分子筛上的吸附特性,烃分子吸附能随碳数的增加而增大。烃分子吸附在H-FAU分子筛上,烯烃和芳烃双键碳原子因具有π电子与分子筛B酸中心间形成π-H键,烷烃、环烷烃与B酸中心间有电子诱导作用,烃分子与分子筛骨架间有范德华作用。烃分子碳数的增加会增大分子与分子筛骨架间的范德华作用,不影响烯烃、芳烃与B酸中心间π-H键作用或烷烃、环烷烃与B酸中心间电子诱导作用。不同类型烃分子与分子筛B酸中心间相互作用由大到小的顺序为直链2-烯烃芳烃直链烷烃环烷烃。     

石脑油中正构烷烃在无黏结剂5A分子筛床层中的吸附行为研究

在固定床吸附分离实验装置上对比研究了石脑油中正构烷烃在无黏结剂和有黏结剂5A分子筛床层中的吸附行为。结果表明,随着碳数的增加,各正构烷烃穿透床层的时间增加。与有黏结剂5A分子筛床层相比,无黏结剂5A分子筛床层具有更高的正构烷烃吸附容量,床层穿透时的油筛比更大。在吸附温度300 ℃、石脑油进料空速90 h-1的条件下,无黏结剂5A分子筛对石脑油中正构烷烃的动态吸附容量较有黏结剂5A分子筛高34.5%。正构烷烃在无黏结剂5A分子筛床层中的传质段长度小于有黏结剂5A分子筛床层,无黏结剂5A分子筛床层的有效利用率更高。     

C_5/C_6正异构烷烃分子筛吸附分离的设计

本文介绍C_5/C_6正异构烷烃分子筛吸附分离系统设计中的工艺条件,如吸附脱附温度和压力等选取的依据、分离过程数的选定、串联吸附和脱附的特点以及吸附塔大小的确定等,还列举了“7塔4过程”的切换操作顺序,并扼要地提出吸附分离-异构化反应-高压分离系统物料衡算的模拟流程方法。     

调和柴油性质对低温性能的影响

利用9种组分柴油调和为调和柴油,通过柱层析色谱和尿素脱蜡分离正构烷烃,并通过气相色谱分析正构烷烃碳数分布,得出结论：柴油正构烷烃含量和平均碳数都是影响降凝剂在调和柴油中感受性的主要因素。当柴油正构烷烃含量小于20%,且平均碳数为18～19时,柴油降凝剂在柴油中的感受性最好。     

Composition and Properties of Some Petroleum Waxes

Structural composition of paraffin waxes and soft wax fraction derived from microcrystalline wax were determined. Waxes were fractionated by multistage solvent crystallization at different temperatures. The n-alkane components of the waxes were separated by urea adduction. The average structural parameters of parent waxes, their fractions, and urea adductables were estimated by ¹h and ¹³C NMR spectroscopy. The thermal parameters viz. phase transition temperature and the associated energy during phase transitions were determined by using DSC and correlated with the penetration temperature behavior of waxes. The carbon number distribution determined by GC for these waxes and their n-alkane components were also correlated with physical properties and thermal parameters.     

Composition and Properties of Some Petroleum Waxes

Abstract

Structural composition of paraffin waxes and soft wax fraction derived from microcrystalline wax were determined. Waxes were fractionated by multistage solvent crystallization at different temperatures. The n-alkane components of the waxes were separated by urea adduction. The average structural parameters of parent waxes, their fractions, and urea adductables were estimated by ¹h and ¹³C NMR spectroscopy. The thermal parameters viz. phase transition temperature and the associated energy during phase transitions were determined by using DSC and correlated with the penetration temperature behavior of waxes. The carbon number distribution determined by GC for these waxes and their n-alkane components were also correlated with physical properties and thermal parameters.     

RHEOLOGICAL PROPERTIES OF BOMBAY HIGH CRUDE OIL IN RELATION TO ITS n-ALKANE COMPONENTS

ABSTRACT

Bombay High crude oil is very waxy in nature and has a high pour point (30^°C), The wax present in it largely consists of solid n-alkanes. Changes in the rheological properties of the crude oil after removal of n-alkanes by urea adduction have been determined. Influence of the concentration of n-alkane components on the rheological properties of non adductable components of crude oil have also been studied.     

THE WETTABILITY OF LOW COAL RANKS IN THE PRESENCE OF N-ALKANES AND DIACETONE ALCOHOL

ABSTRACT

Contact angle measurements were carried out in coal ranks of 32.1 and 32.2/n-alkane film - air bubble - aqueous diacetone solution systems. In these studies n-alkanes in homological series from n-hexane to n-hexadecane and aqueous diacetone alcohol solutions in concentration range from 0 to 10% were used. On the basis of obtained results the adhesion work of aqueous diacetone alcohol solutions to coal surface precovered with n-alkane film was calculated from the modified Young equation. These investigations showed that an increase of n-alkane film thickness causes a decrease of the wettability of low-rank coals as well ob a decrease of the adhesion work of aqueous diacetone alcohol solutions to coal/n-alkane film surface. An increase of the may be also stated, that an increase of the quantity of diacetone alcohol molecules adsorbed on coal surface precovered by a small amount of hydrocarbon causes a decrease of the adhesion work, but when the coal surface is precovered by a big amount of hydrocarbon the adhesion work is increased.

From the practical point of view it seems to be the most profitable circumstance when a thick n-alkane film occurs on coal surface and a small amount of diacetone alcohol is present in water. However, in order to confirm this more detailed studies in this field should be carried out.     

关于我国东部某些现代沉积物正构烷特征与物质来源的讨论

自从 E.E.Bray 和 E.D.Evans(1961)发现近代沉积物中正构烷烃具有奇碳优势,而在成熟生油岩和原油中这种优势趋于消失这一特点之后,奇碳优势的消失被普遍地认为是生油岩业已成熟的重要标志之一。但七十年代以来,我们发现我国东部现代沉积物中不仅存在高碳数奇碳优势正烷烃,也存在偶碳优势正烷烃。     

ANFIS-GA modeling of dynamic viscosity of N-Alkane in different operational conditions

Viscosity is known as one of major properties of fluids which have straight effects on different parts of chemical and petroleum industries. Due to this importance, in the present work, adaptive neuro-fuzzy interference system (ANFIS) was coupled with genetic algorithm (GA) to predict dynamic viscosity of normal alkane in terms of molecular weight of n-alkane, temperature and pressure. In order to prepare and validate the predicting model 228 experimental data points were extracted from the literature. The outputs of this predictive tool were compared with the experimental data and comparisons showed that predicted dynamic viscosities have good agreement with experimental data. According to the statistical and graphical analyses this simple tool can be used as a rigorous and accurate method for prediction of dynamic viscosity of n-alkane, especially at reservoir conditions.     

尿素脱蜡生产L-AN15号全损耗系统用油基础油研究

以江苏原油常三线油为原料,采用异丙醇尿素脱蜡工艺,常温常压下,尿素与正构烷烃络合形成不溶于油的络合物,使其正构烷烃从油中分出.脱蜡油经精制后粘度、倾点和闪点符合L-AN15号全损耗系统用油指标要求.蜡中正构烷烃含量近90%.     

正构烷烃单体碳、氢同位素在油源对比中的应用

以黄骅坳陷古生界烃源岩作为研究对象,采用GC-IRMS和GC-TC-IRMS技术对烃源岩抽提物中的正构烷烃单体碳、氢同位素进行测定,揭示不同沉积环境中正构烷烃单体碳、氢同位素的组成特征。研究结果表明,下古生界烃源岩正构烷烃的δ¹³C和δD值分别为-29‰~-33‰和-110‰~-140‰;上古生界烃源岩正构烷烃的δ¹³C和δD值分别为-27‰~-29‰和-140‰~-170‰.从下古生界的海相到上古生界的海陆过渡相,正构烷烃明显存在一个富δ¹³C和贫δD的趋势。这表明,沉积环境是控制烃源岩正构烷烃氢同位素组成的主要因素。因此,在复杂的含油气系统中,正构烷烃单体碳、氢同位素组成分布特征对油源对比有着重要的意义,并且可用于母质来源及沉积环境的探讨。     

STUDIES ON THE PLOW PROPERTIES OF VACUUM GAS OIL FRACTION FROM BOMBAY HIGH CRUDE OIL IN RELATION TO ITS COMPOSITION

The vacuum gas oil fraction 375-Crude oil is highly waxy in nature associated with high pour point (48°C). Influence of various hydrocarbon constituents viz. n-alkane, aromatic and iso + cycloparaffins on the cold flow properties of this fraction was studied. Also the dependency of nature and boiling range of liquid hydrocarbon solvent matrix on the response towards cold flow properties as a function of n-alkane concentration have been determined. It is observed that the flow properties viz. pour point, plastic viscosity and yield stress in the non-Newtonian region are a result of wax liquid matrix interaction.