High-energy ionising radiation initiated decomposition of acetovanillone

Hydroxyl radical, hydrated electron and hydrogen atom intermediates of water radiolysis react with acetovanillone with rate coefficients of (1.05 +/- 0.1) x 10(10), (3.5 +/- 0.5) x 10(9) and (1.7 +/- 0.2) x 10(10) mol(-1) dm(3) s(-1). Hydroxyl radical and hydrogen atom attach to the ring forming cyclohexadienyl type radicals. The hydroxyl-cyclohexadienyl radical formed in hydroxyl radical reaction in dissolved oxygen free solution partly transforms to phenoxyl radical. In the presence of O-2 phenoxyl radical formation and ring destruction are observed. Hydrated electron in O-2 free solution attaches to the carbonyl oxygen and undergoes protonation yielding benzyl type radical. In air saturated 0.5 mmol dm(-3) solution using 15 kGy dose most part of acetovanillone is degraded, for complete mineralisation five times higher dose is required. The experiments clearly show that acetovanillone can be efficiently removed from water by applying irradiation technology. (C) 2011 Elsevier Ltd. All rights reserved.