Pollard Hydrocarbons

Pollard, Eniest 1., Synchronous Motors. . . Avoid Torsional Vibration Problems, Hydrocarbon Processing, February 1980, pp. 97-102. 

Pollard, E. L, Synchronous Motors—Avoid Torsional Vibration Problems, Hydrocarbon Processing, p. 97, Eeb. (1980). 

Further support for the attainment of a critical concentration of hydroperoxide prior to the passage of a cool flame at temperatures corresponding to the Lq and L, lobes has been obtained by Taylor [131], and more recently by Pollard and co-workers [68,132], who determined the maximum concentrations of tert-butyl hydroperoxide found during the cool-flame oxidation of isobutane. Again, the concentration of hydroperoxide increased prior to the cool flame and it was almost entirely consumed during its passage (Fig. 12). Also, in common with other hydrocarbon + oxygen systems, (e.g. refs. 55, 65, 78,133) the induction period to the first cool flame (r,) was related to the initial reactant pressure (po) by the expression... 

Baldwin and Walker [99] have pointed out that, from kinetic considerations, surface reactions of alkylperoxy radicals cannot play a significant role except at very low overall rates of reaction and conclude that it is more likely that surface destruction of relatively stable intermediates such as the alkyl hydroperoxides or hydrogen peroxide are the main cause of surface effects in hydrocarbon oxidation. Luckett and Pollard [68, 134] have provided evidence, which suggests that the surface destruction of tert-butylhydroperoxide is indeed important during the oxidation of isobutane below ca. 320 °C. Since isobutene and acetone are known products of the decomposition of tert-butylhydroperoxide, it is clear that many of the foregoing results can be explained in these terms, but if this is the predominant heterogeneous reaction the yield of acetone would be... 

A. J. Brown, N. Burt, G. A. Luckett and R. T. Pollard, Symposium on the Mechanisms of Hydrocarbon Reactions, Siofok, Hungary, 1973. 

Dale MJ, Jones AC, Pollard JT, et al. 1993. Application of two-step laser mass spectrometry to the analysis of polynuclear aromatic hydrocarbons in contaminated soils. Environ Sci Technol 27 1693-1695. 

Pollard SJ, Hrudey SE, Fuhr BJ, et al. 1992. Hydrocarbon wastes at petroleum- and creosote-contaminated sites Rapid characterization of component classes by thin-layer chromatography with flame ionization detection. Environ Sci Technol 26(12) 2528-2534. 

Whittaker, M. Pollard, S.J.T. (1994) Characterisation of refractory wastes at hydrocarbon-contaminated sites 1. Rapid column fractionation and thin layer chromatography of reference oils. Journal of Planar Chromatography, 7(5), 354. 

Chesterfield, J. and I.D. Entwhistle Methods for the separation of cigarette smoke hydrocarbons 17th Tobacco Chemists Research Conference, Program Booklet and Abstracts, Vol. 17, Paper No. 24, 1963, pp. 17-18. Chibnall, A.C., S.H. Piper, A. Pollard, E.R Williams, and P. Sahai The constitution of the primary alcohols, fatty... 

Burleson, G. R., M. J. Caulfield, and M. Pollard. 1979. Ozonation of mutagenic and carcinogenic polyaromatic amines and polyaromatic hydrocarbons in water. Cancer Res. 39 2149-2154. 

Pollard SJT, Hmdey SE, Eredorak PM. (1994). Bioremediation of petroleum and creosote-contaminated soils A review of constraints. Waste Management Research 12 173-194. Potter TL, Simmons KE. (1998). Composition of petroleum mixtures. In Total Petroleum Hydrocarbon Criteria Working Group Series, Vol. 2. Amherst, MA Scientific Pnbhshers Amherst. 

The role of surface in the formation of products in hydrocarbon oxidation has been discussed frequently. Knox has suggested that in the oxidation of isobutane at about 575 K, isobutene is formed homogeneously, but that other products are formed in surface reactions of RO -. Barnard and Lee, however, find no pentenes in a shock-tube study of the oxidation of n-pentane at 925—1125 K, in which surface reactions should be unimportant, and suggest that this supports Pollard s view that conjugate alkene is formed at the vessel surface. This interpretation can be discounted because radical decompositions should dominate at these temperatures, particularly at the rather low O pressures used, so that coiuugate alkene would at most be a very minor product. Recently, studies of the addition of n-butane to slowly reacting mixtures of H + O at 753 K using... 

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