Naphthalene oxidation in supercritical water

Characteristic features of naphthalene oxidation and the kinetics of naphthalene pyrolysis in supercritical water (SCW) were studied using a batch reactor under isobaric conditions at a pressure of 30 MPa, in the temperature range from 660 degreesC to 750 degreesC, and for different levels of oxygen supply, varying from 0 to 2.5 moles of O-2 per mole of naphthalene. The pyrolysis produces benzene, toluene, methane, hydrogen, soot, and carbon oxides:. The rate constant for naphthalene pyrolysis in SCW was found to be k = 10(12.3+/-0.2)exp(-E/T) s(-1) where E = 35400+/-500 K. For T > 660 degreesC, water participates in the chemical reactions of naphthalene conversion, Particularly, in the formation of carbon oxides. The conversion of naphthalene in pure SCW is accompanied by heat evolution. Molecular oxygen oxidizes a part of naphthalene completely, i.e., to CO2 and H2O, this reaction being so prompt that in some cases, self-heating of the mixture and thermal explosion in the reactor were observed.