Hydrocarbon solvents composition

Anhydrous Mgl2 is used in a process for producing organometaUic and organobimetaUic compositions, which are important in the preparation of pharmaceutical and special chemicals. An organic haUde, an alkaU metal, and magnesium haUde react in a Hquid hydrocarbon solvent (66). 

Hydrocarbon Solvents. Most hydrocarbon solvents are mixtures. Few commercial hydrocarbon solvents are single compounds. Toluene is an exception. Hydrocarbon solvents are usually purchased and suppHed on specification. The most important specification properties are distillation range, solvency as expressed by aniline cloud poiat and Kauri-Butanol (KB) value, specific gravity, and dash poiat. Composition requirements such as aromatic content and benzene concentration are also important ia many appHcations. 

Hydrocarbon solvents marketed by each manufacturer differ ia composition from those of other manufacturers, even if the specification properties are similar. This means that hydrocarbon solvents are not specified on the basis of molecular content. The composition of a hydrocarbon solvent depends on the cmde feed to the process as well as the specific process steps the solvent undergoes duriag manufacture. Because each manufacturer uses a different feed and a somewhat different manufacturiag scheme, hydrocarbon solvents differ somewhat ia thek properties, even ia situations where the solvent performs the same. 

Bota et al. [84] used the PCA method to select the optimum solvent system for TLC separation of seven polycyclic aromatic hydrocarbons. Each solute is treated as a point in a space defined by its retention coordinates along the different solvent composition axes. The PCA method enables the selection of a restricted set of nine available mobile phase systems, and it is a useful graphical tool because scatterplots of loading on planes described by the most important axes will have the effect of separating solvent systems from one other most efficiently. 

Dispersant compositions for the treatment of oil spills at the surface of the water consist of a mixture of water, a hydrocarbon solvent, and a mixture of surfactants consisting of 55% to 65% by weight of emulsifiers and 35% to 45% by weight of dioctyl sodium sulfosuccinate. The emulsifying agents consist of a mixture of various sorbitan oleates [351-354]. 

Compositions of a N,N-dialkylamide of a fatty acid in a hydrocarbon solvent and a mutual oil-water solvent are useful for the prevention of sludge formation or emulsion formation during the drilling or workover of producing oil wells [1526,1528,1529]. 

Polymer Synthesis and Characterization. This topic has been extensively discussed in preceeding papers.(2,23,24) However, we will briefly outline the preparative route. The block copolymers were synthesized via the sequential addition method. "Living" anionic polymerization of butadiene, followed by isoprene and more butadiene, was conducted using sec-butyl lithium as the initiator in hydrocarbon solvents under high vacuum. Under these conditions, the mode of addition of butadiene is predominantly 1,4, with between 5-8 mole percent of 1,2 structure.(18) Exhaustive hydrogenation of polymers were carried out in the presence of p-toluenesulfonylhydrazide (19,25) in refluxing xylene. The relative block composition of the polymers were determined via NMR. 

The supplier of hydrocarbon solvent prepares the solvent by blending different solvents and organic compounds. The company does not disclose the exact composition of the solvent, only stating that it is a mixture of toluene, butanol and ethanol with a 40-50% toluene content. The different constituents are bought at the local market. The prepared solvent contains traces of water and heavy residues. 

Hydrogen-deuterium exchange in alkanes shows the same dependence on the composition of solvent, and concentration of mineral acid, of platinum( 11) and of chloride ions as does the exchange in aromatic hydrocarbons. The dependence of the exchange rate on solvent composition has been discussed in Section III,B,1. The rate is independent of mineral acid concentration, increases nonlinearly with increase in the concentration of platinum 11), and decreases nonlinearly with increase in the concentration of chloride ions (55). The nonlinear dependences are due to the solvolysis of the PtCL,2- ion ... 

Usually, the composition of commercial extractants is proprietary information, but a typical example is an cc-hydroxyoxime carried in a hydrocarbon solvent such as kerosene. 

An example of such a catalyst system is racemic isopropylene bis(l-indenyl) zirconium dichloride in combination with an alumi-noxane (21). The reaction is carried out in hydrocarbon solvents, e.g., toluene. A solution of norbornene in toluene with the catalyst is degassed and then pressurized with ethene. The polymerization is carried out while stirring at 70°C under constant ethylene pressure at 18 bar. After completion, the polymer is precipitated in acetone and filtered (21). The cycloolefin copolymers obtained in this way have a high thermal shape stability and it is possible to use the polymers as thermoplastic molding compositions. 

In hydrocarbon solvents it is known that most of the growing chains are associated and it is necessary to enquire what effect this has on the copolymerization mechanism. The reactivity ratios measured from copolymer composition are unaffected because they refer to a common ion-pair. The equilibrium constants for association cancel and the reactivity ratios measured give a true measure of the relative propagation constants of the two monomers. No assessment can be made of the real reactivity of two types of active chain with the same monomer, however. In this case the observed rates are a function of the relative reactivities of the free ion-pairs and also of the relative extents of association. For example in hydrocarbon solvents polystyryllithium reacts with butadiene much more rapidly than does polybutadienyllithium. Until we know the two equilibrium constants for self-association we cannot find out if the increased rate is due to greater intrinsic reactivity or to a higher concentration of free polystyryllithium. In polar solvents or in hydrocarbon solvents in the presence of small amounts of ethers, these difficulties do not arise as self-association is no longer important. 

When pentane and the lower molecular weight hydrocarbon solvents are used in large excess, the quantity of precipitate and the composition of the precipitate changes with increasing temperature (Mitchell and Speight, 1973 Andersen, 1994). 

It is seen that Eq. (3.119) adequately fits the experiment at the significance level a=0.05%. The quality of the resultant product is considered satisfactory, if the content of residual hydrocarbons in the biomass is under 0.05%. With the aim to elucidate the solvent compositions meeting this requirement, the lines of constant response are plotted to Eq. (3.119) the curves are shown in Fig. 3.24. The solvent compositions meeting the requirement that y<0.05%, can be found within the area of the simplex. 

The use of borane-containing monomers clearly presents an effective and general approach in the functionalisation of polyolefins, which has the following advantages stability of the borane moiety to coordination catalysts, solubility of borane compounds in hydrocarbon solvents (such as hexane and toluene) used as the polymerisation medium, and versatility of borane groups, which can be transformed to a remarkable variety of functionalities as well as to free radicals for graft-form polymerisations. The functionalised polymers are very effective interfacial modifiers in improving the adhesion between polyolefin and substrates and the compatibility in polyolefin blends and composites [518],... 

In the inert hydrocarbon solvents used an insoluble mixed halide-alkyl complex of aluminium and titanium is formed of variable composition. This material is the active catalyst for the polymerisation of ethylene, persumably acting as a heterogenous catalyst. 

It has been demonstrated that electrochemical deposition of fullerene-containing films from the TFE solutions on the nickel electrodes is possible in principle. It has been found that the thickness, structure, density and chemical composition of the films depend heavily on the type of hydrocarbon solvents for fullerenes, the chemical composition of a base electrolyte and conditions for electrolysis. 

In the studies carried out to date, eight fuels have been tested which include six synfuels and two petroleum derived fuels. The synfuels tested included SRC-II middle and heavy distillate fuels, a blend of these fuels, and one SRC fuel blended with the process donor solvent. Composition data for the various fuels are presented in Table I, where it can be seen that the coal derived liquids have a higher C H ratio than either the diesel or residual petroleum oils, indicative of a higher aromatic hydrocarbon content. The shale-derived DFM on the other hand is a highly processed fuel and has a C H ratio similar to the petroleum diesel oil. Complete analyses of all the actual fuels tested were unfortunately not available at the time of writing, and, where necessary, typical analyses have been taken from previous studies. 

Hydrocarbons. Contrary to popular belief, some Grignard reagents are appreciably soluble in hydrocarbons, but their solubility is often low, and the composition of the solutes is variable, so purely hydrocarbon solvents... 

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