Benzene solubles

Tars can be hydrogenated to produce Hquid fuels. High hydrogen and low asphaltene, ie, benzene-soluble and pentane-iasoluble, contents are desirable. The central German brown coals are attractive for this reason. The tars from the eastern part of Germany require much lower pressures and less hydrogen per unit of product than do brown coals near Cologne, which can require pressures up to 71 MPa (700 atm) (see Petroleum). 

A mild and effective method for obtaining N- acyl- and N- alkyl-pyrroles and -indoles is to carry out these reactions under phase-transfer conditions (80JOC3172). For example, A-benzenesulfonylpyrrole is best prepared from pyrrole under phase-transfer conditions rather than by intermediate generation of the potassium salt (81TL4901). In this case the softer nature of the tetraalkylammonium cation facilitates reaction on nitrogen. The thallium salts of indoles prepared by reaction with thallium(I) ethoxide, a benzene-soluble liquid. 

Coal tar pitch volatiles, see Particulate polycyclic aromatic hydrocarbons (PPAH), as benzene solubles Cobalt metal, dust and fume (as Co)... 

Corynantheidine, C22H28O3N2. This isomeride of corynantheine was found by Janot and Goutarel (1944) in the residual, benzene-soluble alkaloids of Pseudocinchona africana. It was isolated as the picrate, m.p. 252°, — 152° (acetone). The base, B. COMe2, had m.p. 117°,... 

Two unnamed alkaloids have also been deseribed. One was obtained by Bredemann in work on the alkaloids of white hellebore it occurred in the mother liquors from protoveratrine crystallisation and formed spherical aggregates of needles, m.p. 239-241°. The other was isolated by. Jacobs and Craig during a chromatographic analysis of residual, benzene-soluble alkaloids of green hellebore. It is represented by the formula C27H41 (39)04N, crystallises in six-sided platelets or flat needles, sinters about 130°, effervesces at 170-5°, and on further heating solidifies and finally melts at 272-4° it has [a]n ° — 78° (MeOH). 

Thiophene is also metal ated by a benzene-soluble ethyl sodium-diethyl zinc complex. Upon carbonation, 65% of 2-thiophenecar-boxylic acid was obtained. ... 

In usual PVC 1.53-2.54 allylic chlorines per 1,000 monomer units and in a benzene-soluble low-molecular weight PVC fraction, a higher value of 3.07 allylic chlorines per 1,000 monomer units was obtained. This method has come under certain criticism because it was found to give significantly higher values for labile (allylic) chlorines than do other methods, e.g., phenolysis [50]. 

Treatment of cis- or ira x-3,4-dibromo-2,3,4,7-tetrahydrothiepin 1,1-dioxide with 2 equivalents of triethylamine in benzene solution at 25 CC gives, after chromatography of the benzene-soluble products, thiepin 1,1-dioxide.15... 

PDMT = Me2N(CH2)2NMe(CH2)2NMe2) while salts with other large cations like Bu4NAuR4 (R = Me, Et) are benzene soluble [171]. 

In modern terms, asphaltene is conceptually defined as the normal-pentane-insoluble and benzene-soluble fraction whether it is derived from coal or from petroleum. The generalized concept has been extended to fractions derived from other carbonaceous sources, such as coal and oil shale (8,9). With this extension there has been much effort to define asphaltenes in terms of chemical structure and elemental analysis as well as by the carbonaceous source. It was demonstrated that the elemental compositions of asphaltene fractions precipitated by different solvents from various sources of petroleum vary considerably (see Table I). Figure 1 presents hypothetical structures for asphaltenes derived from oils produced in different regions of the world. Other investigators (10,11) based on a number of analytical methods, such as NMR, GPC, etc., have suggested the hypothetical structure shown in Figure 2. 

Figure 3 shows GPC fractionation of the benzene extract of a vitrinite which, before a single non-reductive ethylation, was treated with tetrahydronaphthalene at 390°C. Although hydrogenation reduced the -OH contents (from 4.9 to 1.7%), non-reductive alkylation increased the benzene-solubility of the solvolyzed material from 53% to 80.2%. It appears that this effect is due to ethylation of acidic atoms. 

Effect of Product Wash. For several runs, the product slurries were divided after water quenching of the MTC, and 15 ml HC1 was added to the cold water wash. Figure 7 shows the increase in benzene and total MTC solubility as a result of the HC1 wash. Acid-washing produces total pyridine solubility from a 65% soluble water-washed MTC. The effect of acid washing on benzene solubility is less marked, with a maximum increase of 10-15% when the water-washed benzene solubility is 25%. The maximum benzene solubility with either water or acid wash is 40%. 

In some runs, a preliminary benzene wash was necessary to make the MTC sufficiently hydrophilic to allow removal of the ZnCl2 The amount of solubilized material from the wash was added to the benzene Soxhlet yield, to give the total benzene solubility. As seen in Figure 8, relative to water-washed MTC, benzene-washed MTC has higher benzene solubility with the same... 

Figure 7. Effect of acid wash on solubilities compared with water wash 273 g ZnClg, 50 g coal. Total solubility is the sum of benzene solubility and incremental...

Figure 8. Relations between benzene solubility and total (pyridine) solubility 273 g ZnCl2, 50 g coal Wash (M)> benzene ( 7), HzO (%), HCl...

Figure 1. Liquefaction yields vs. maximum fluidities in the fused state of coal (%), solvent (SRC pitch benzene soluble) (O), pyrene ((B), no solvent. Coal.sol-vent ratio = 1 3 reaction temperature = 390°C(8).

The recovery percentages of coal and solvent (BI/ coal fed, BS/solvent fed, respectively) calculated based on the above assumption are summarized in Table 4. They were more than 85% except for the significantly low value for the coal recovery when hydropyrene was used as the solvent. In the latter case, some extent of the coal may be converted into the benzene soluble. Nevertheless, analyses of BS and BI fractions may inform the structural change of coal and solvent after the liquefaction. 

To summarize our effort, we found that C0/H20/K0H systems converted Illinois No. 6 coal to a material which was fully pyridine soluble, 51% benzene soluble, and 18% hexane soluble. As with the basic alcoholic systems, there were significant reductions in organic sulfur levels, and moderate reductions in nitrogen levels. 

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