Application of chemical equilibrium for hydrocarbon isomerization analysis

Isomerization is used in refining industry to upgrade gasoline. Since it is an important process, it is desirable to analyze the reactions that take place in the process. In this paper, the isomerization of a mixture of hydrocarbons was modeled by solving the chemical equilibrium of the system. A direct application of the chemical equilibrium solution cannot reproduce experimental results. However, when some of the system reactions are molar extent limited, the solution can reproduce published experimental data.     

吐哈油田生产井蜡沉积物系统分析及蜡沉积机理探讨

用溶剂萃取分离，气相色谱，红外光谱、核磁共振等方法分析研究了吐哈油田特别是鄯善油田生产井的蜡沉积物，吐哈原油中的蜡按烷烃碳数分布有Ｃ１３－Ｃ３５和Ｃ３０－Ｃ６５两个峰区，其中第二峰区的高碳石蜡含量超过蜡总含量的５０％，蜡熔点很高，为８４－１００℃，基本上是不带支链的纯粹正构烷烃，极易从原油中析出。对蜡沉积作了初步探讨和推论。     

Surface diffusion of strong adsorbing vapours on porous carbon

Surface diffusion of strongly adsorbing hydrocarbon vapours on activated carbon was measured by using a constant molar flow method (D.D. Do, Dynamics of a semi-batch adsorber with constant molar supply rate: a method for studying adsorption rate of pure gas, Chem. Eng. Sci. 50 (1995) 549), where pure adsorbate is introduced into a semi-batch adsorber at a constant molar flow rate. The surface diffusivity was determined from the analysis of pressure response versus time, using a linear mathematical model developed earlier. To apply the linear theory over the non-linear range of the adsorption isotherm, we implement a differential increment method on the system which is initially equilibrated with some pre-determined loading. By conducting the experiments at different initial loadings, the surface diffusivity can be extracted as a function of loading. Propane, n-butane, n-hexane, benzene, and ethanol were used as diffusing adsorbate on a commercial activated carbon. It is found that the surface diffusivity of these strongly adsorbing vapours increases rapidly with loading, and the surface diffusion flux contributes significantly to the total flux and cannot be ignored. The surface diffusivity increases with temperature according to the Arrhenius law, and for the paraffins tested it decreases with the molecular weight of the adsorbate.     

Effects of connate water on chemical flooding processes in porous media

This work examines the effects of connate water on the unstable displacement patterns and fractional oil recoveries observed when simulated secondary and tertiary oil displacement processes are conducted in the laboratory. Three displacement systems were investigated; a non-reacting system without surfactant (water displacing non-acidic paraffin oil), a non-reacting system with externally added surfactant (sodium dodecyl sulfate solution displacing non-acidic paraffin oil), and a reacting system with internally generated surfactant (sodium hydroxide solution displacing acidified paraffin oil). A consolidated porous medium constructed of fused glass beads was used to simulate the underground oil reservoir. Each of the three basic displacement processes was conducted both in the absence and presence of connate water, and at three different flow rates. The results obtained indicate that the presence of connate water can exert a significant influence on the displacement pattern with the non-reacting systems, particularly at low flow rates. Some of these effects include an increase in the number of fingers and/or much thinner fingers with many tiny branches. At low flow rates, the presence of connate water tends to decrease the breakthrough oil recovery for the non-surfactant system, but increases the breakthrough recovery for the surfactant-containing systems. At high flow rates, connate water has a much less pronounced effect due to the dominance of viscous forces.     

Katalysatoren des Leuna Werkes 1945 – 1991: Von der Empirie zur Wissenschaft. Teil II: Reformier‐ und Isomerisierungskatalysatoren

Subject of the first part of this publication series was the development and manufacturing of technical catalysts within the Leuna Werke company from 1921 – 1945. Part II as well as part III and IV will focus on this topic as well, looking at the years from 1945 to 1991. Within this timeframe, a high‐performing research and development as well as an efficient production line for new catalysts was implemented, facing a new and challenging macroeconomic environment. In recognition of the fact that the first newly developed catalyst after WW II was a reforming catalyst, this article will describe the development path of this group of catalysts as well as the closely related isomerization catalysts.     

Study of individual hydrocarbon's composition of gasoline fraction of Tamsagbulag oil, Mongolia

In order to conduct complex research in oil that originated in Mongolia for further application of petroleum not only as fuel but also as raw material for organic synthesis, we need to study the physical and chemical characteristics, individual and group hydrocarbon's composition of main petroleum fractions. A number of studies and surveys on the physical and chemical characteristics, group hydrocarbon's composition of petroleum deposits in Zuun-Bayan, Sukhaibulag, Tsagaan Elst, Tamsagbulag have been carried out earlier through n-g-M, aniline point, dispersimetric methods successfully. Yet a detailed chromatographical and NMR spectroscopic study for individual hydrocarbon's composition of Tamsagbulag oil main fractions has not been conducted. In the present study, the results of GC analyses of gasoline fractions of wells 19-3, 19-13 and 19-10, Tamsagbulag, Eastern Mongolia were presented. The gasoline fractions of given wells are characterized by high concentration of paraffins and presence of trace amount of olefins. A total of 69 paraffins, 45 naphthenes, 41 aromatics and 3 olefins were identified, totalling 158 individual hydrocarbons from each samples of gasoline fraction. The first attempts to classify Tamsagbulag oil under individual hydrocarbon composition data were successfully conducted and the hypothesis (supposition) of a genetic classification of given oil as “sapropelic” type was made.     

链烷烃分子结构设计（Ⅱ）：基于基团组合的分子构造

在已知链烃构成基团种类与个数的基础上，提出基于基团组合的链烃分子构造方法与结构子图的同构图区分方法。该法具有计算速度快、工作量小、易于在微机上实现等优点。     

链烷烃分子结构设计(I)分子构成基团的确定

以链烃一阶分子连接性指数及其与状态方程参数的关系为基础，利用神经元网络预测与之对应的。然后根据、确定分子结构的路径指数并将其转换为与分子结构，构成基团相关的顶点度数，从而确定构成基团的种类与个数。     

Form-stable phase change materials for thermal energy storage

The present paper considers the state of investigations and developments in form-stable phase change materials for thermal energy storage. Paraffins, fatty acids and their blends, polyethylene glycol are widely used as latent heat storage component in developing form-stable materials while high-density polyethylene (HDPE), styrene-butadiene-styrene (SBS) triblock copolymer, Eudragit S, Eudragit E, poly (vynil chloride) (PVC), poly (vynil alcohol) (PVA) and polyurethane block copolymer serve as structure supporting component. A set of organic and metallo-organic materials with high transition heat in solid-solid state is considered as perspective for-stable materials to store thermal energy. Another perspective class of form-stable materials are the materials on the basis of such porous materials as expanded perlite and vermiculite impregnated with phase change heat storage materials. The technology of producing new form-stable ultrafine heat storage fibers is developed. It opens availability to produce the clothers with improved heat storage ability for extremely cold regions. The perspective fields of application of form-stable materials are discussed. The further directions of investigations and developments are considered.     

GC-MS测定纺织品或皮革中的短链氯化石蜡

以正己烷为提取溶剂,超声提取,0.45μm有机相微孔滤膜过滤,建立了气相色谱-质谱联用技术测定纺织品或皮革中短链氯化石蜡的检测方法。对色谱柱类型进行了选择,并对提取条件进行了优化。在本文研究范围内标准曲线呈线性关系,相关系数0.9995。进行了不同浓度的加标回收率实验,测得回收率均在90.42%～94.22%,相对标准偏差小于10%。该方法简便快捷、灵敏度高,测定低限为1.5μg/mL。