Radiolysis of benzene

Aromatic radical-cations are generated by pulse-radiolysis of benzene derivatives in aqueous solution. Radiolysis generates solvated electrons, protons and hydroxyl radicals. The electrons are converted by reaction with peroxydisulpbate ion to form sulphate radical-anion, which is an oxidising species, and sulphate. In another proceedure, electrons and protons react with dissolved nitrous oxide to form hydroxyl radicals and water, Hydroxyl radicals are then made to react with either thallium(i) or silver(i) to generate thallium(ii) or silver(ll) which are powerfully... 

Sens, (pulse radiolysis of benzene Determination of energy transfer 369... 

In another recent paper, Van Dusen and Hamill69 have examined the effects of various additives on the radiolysis of benzene solutions. They conclude that the indirect effects they observe are due to charge transfer and electron attachment. 

Sens, (pulse radiolysis of benzene energy transfer to naphthalene, anthracene, benzophenone, benzil) Determination of energy transfer efficiencies 369... 

The radiolysis of benzene has been the subject of many studies in both the liquid phase and the gas phase. In all cases the radiolysis leads mainly to polymer formation, but hydrogen and acetylene as well as other minor products are formed in much lower yields. 

A triplet with a splitting constant of 50 Gauss has also been observed in the solution radiolysis of benzene and definitively assigned to a cyclo-hexadienyl radical [113]. 

Tladiation chemists have been aware for about 15 years that the presence of dilute solutes in liquid hydrocarbons can change the course of radiation chemical reactions by other than the normally expected secondary radical reactions. For example, Manion and Burton (40) in early work on the radiolysis of benzene-cyclohexane solutions, drew attention to the possibility of energy transfer from solvent to solute. Furthermore, it is known that in hydrocarbon solvents certain solutes are capable of capturing electrons, thus interfering with the normal ion-recombination process (14, 20, 65, 72). Though ionic products can be observed readily in hydrocarbon glasses [e.g., (19, 21)] demonstration of effects which can be specifically ascribed to electron capture in the liquid state has been elusive until recently. Reaction of positive ions prior to neutralization can play an important role as demonstrated recently by studies on... 

Vapor-Phase y-Radiolysis of Benzene, Toluene, Ethylbenzene, and the Xylenes... 

To provide further information on this point, we have investigated the y-radiolysis of benzene, toluene, ethylbenzene, and the xylenes in the vapor phase and have determined yields of the gaseous products, 4 polymer, and some products of intermediate volatility. These results are compared with those of parallel irradiations of liquid toluene and o-xylene and with published (2, 12) data for the other hydrocarbons in the liquid phase. 

Our results on the y-radiolysis of benzene, toluene, ethylbenzene, and the xylenes in the vapor phase, and of toluene and o-xylene in the... 

Table I. y—Radiolysis of Benzene, Toluene, and Ethylbenzene in Vapor and Liquid Phase...

Table 11.3. y-radiolysis of benzene yields of major products ... 

The yield of H2 in the y-radiolysis of benzene is only 0.004 pmol i.e., it is ca. 100 times smaller than the G(H2) of liquid cyclohexane. It should be noted, however, that the H2 yield is much higher when instead of y rays high LET a rays or accelerated heavy ions are used for irradiation (LaVerne and Schuler 1984). The major products from benzene and also from other aromatic hydrocarbons are dimers and higher-molecular-weight compounds that are called polymer. The yield of dimers and the polymer in y-radiolysis of benzene is 0.08 pmol... 

The mechanism involving MR species is supported by data from the radiolysis of benzene-methanol and pyridine-methanol mixtures where yields of scavenging products reach a maximum at 20-30% concentration of aromatic in methanol. This same concentration region is where styrene-methanol reaches a grafting maximum in the current work. 

The 5 r-electron benzene radical cation 7 is highly reactive but was observed in 1983 by radiolysis of benzene in a CFCI3 matrix at 4.2 K, and the ESR... 

Schuler, R.H., Radiolysis of benzene by heavy ions, Trans. Faraday Soc., 61,100,1965. 

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