Hydrocarbons synthesis product data

Hexachlorobutadiene may be released to soil by disposal of wastes in landfill operations. In 1982, only 0.2% of the 27 million pounds of hexachlorobutadiene waste produced as a by-product of chlorinated hydrocarbon-synthesis was disposed of in landfill operations (EPA 1982b). These data indicate that the release to soil was approximately 54,000 pounds. According to TRI90 (1992), no hexachlorobutadiene was discharged to the soil from manufacturing and processing facilities in the United States in 1990 (see Table 5-1). The TRI data should be used with caution since only certain types of facilities are required to report. This is not an exhaustive list. 

Production, Import/Export, Use, Release, and Disposal. Hexachlorobutadiene is not produced for commercial purposes in the United States, however small amounts are imported from Germany. Hexachlorobutadiene is mainly produced as a by-product of chlorinated hydrocarbon synthesis and is a primary component of "hex-wastes" (EPA 1982b). Its uses as a pesticide and fumigant have been discontinued. Hexachlorobutadiene is disposed chiefly by incineration, and to a lesser extent by deep well injection and landfill operations (EPA 1982b). More recent production and release data would be helpful in estimating human exposure to hexachlorobutadiene. 

Additional data on the compositions of both hydrocarbon and oxygenated products of hydrocarbon synthesis have been presented by Morrell et al. (59). 

Results were also obtained for the conversion of syngas containing C-labeled eth-ene or propene using a precipitated promoted iron catalyst. In addition, a fused iron catalyst was employed in a run with labeled ethene at 20 atm pressure. They found that the cracking reaction of ethene was of secondary importance with the iron catalyst, unlike the case with cobalt. The distribution of the synthesis products from C-ethene showed that about 50 percent of the transformation was to the C3 product the transformation to higher hydrocarbons decreased much quicker than for the cobalt normal pressure synthesis (Figure 33). With the addition of C-ethene the iso-paraffins had a lower activity than the normal paraffins this is consistent with the data for cobalt (Figure 34). 

Dente and Ranzi (in Albright et al., eds.. Pyrolysis Theory and Industrial Practice, Academic Press, 1983, pp. 133-175) Mathematical modehng of hydrocarbon pyrolysis reactions Shah and Sharma (in Carberry and Varma, eds.. Chemical Reaction and Reaction Engineering Handbook, Dekker, 1987, pp. 713-721) Hydroxylamine phosphate manufacture in a slurry reactor Some aspects of a kinetic model of methanol synthesis are described in the first example, which is followed by a second example that describes coping with the multiphcity of reactants and reactions of some petroleum conversion processes. Then two somewhat simph-fied industrial examples are worked out in detail mild thermal cracking and production of styrene. Even these calculations are impractical without a computer. The basic data and mathematics and some of the results are presented. 

The data available for heterogeneous Fischer-Tropsch catalysts indicate that with cobalt-based catalysts the rate of the water gas-shift reaction is very slow under the synthesis conditions (5). Thus, water is formed together with the hydrocarbon products [Eq. (14)]. The iron-based catalysts show some shift activity, but even with these catalysts, considerable quantities of water are produced. 

For the structural analysis of cyclic fatty acid derivatives (polymerized drying oils, copolymerization products of fatty oils with various hydrocarbons), in principle the same graphical methods can be developed as have been described for the investigation of hydrocarbon mixtures. However, the construction of useful graphical representations is hampered by the fact that reliable data on physical constants are restricted to the normal saturated fatty acids and their methyl and ethyl esters the synthesis of pure unsaturated fatty acids is already extremely difficult, to say nothing of more complicated cyclic or branched compounds. 

Thus, in accordance with the data of [1367], the synthesis of Ni(OR)2 suggested by Mehrotra [99] leads, in fact, to LinNi(OR)18+0Clo 2 (R = Me, Et). In the synthesis of metal alkoxides highly soluble in hydrocarbons (with branched or chelated radicals) both LiOR or NaOR may be used. The product is usually extracted by hexane, EtjO, or other low-boiling solvents, such as... 

Hydrocarbon distributions in the Fischer-Tropsch (FT) synthesis on Ru, Co, and Fe catalysts often do not obey simple Flory kinetics. Flory plots are curved and the chain growth parameter a increases with increasing carbon number until it reaches an asymptotic value. a-Olefin/n-paraffin ratios on all three types of catalysts decrease asymptotically to zero as carbon number increases. These data are consistent with diffusion-enhanced readsorption of a-olefins within catalyst particles. Diffusion limitations within liquid-filled catalyst particles slow down the removal of a-olefins. This increases the residence time and the fugacity of a-olefins within catalyst pores, enhances their probability of readsorption and chain initiation, and leads to the formation of heavier and more paraffinic products. Structural catalyst properties, such as pellet size, porosity, and site density, and the kinetics of readsorption, chain termination and growth, determine the extent of a-olefin readsorption within catalyst particles and control FT selectivity. 

Although addition of alkali metal reduced the catalytic activity of Fe UFP for FT synthesis, catalyst deactivation was suppressed by alkali promotion. Figure 2 shows the average STY s of hydrocarbons, oxygenates, and CO2 over the Fe UFP catalysts promoted by various kinds of alkali metals in a comparison with the precipitated catalyst. These data were taken for the products in the initial 6 hr of run. The activities of UFP catalysts were higher than that of the ordinary K-promoted Fe precipitation catalyst, in spite of comparable surface areas. This is interpreted as due to an effect of surface structure of catalyst. In the case of the precipitated catalyst having a rather porous structure compared with UFP, the reactant diffuses into the pores and reacts on the catalyst surface. If the reaction is faster than diffusion processes, the concentration of reactant falls along with the distance from the pore mouth. Thus, a limited portion of the surface of the precipitated catalyst can be used for reaction (ref. 7). 

The highly exothermic character of the synthesis is shoivn by the data. Except for formation of methane which is even more exothermic, about 38-42 kcal per carbon atom is liberated in the synthesis of the paraffins when water is the oxygenated product and 47-50 kcal when carbon dioxide is formed. Slightly less heat is liberated in the synthesis of olefins. The heat of reaction amounts to about 70 Btu per cu ft of sjmthesis gas reacting, or to about 7000 Htu per lb of hydrocarbon produced. 

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