Pulse Radiolysis Study of Concentrated Phosphoric Acid Solutions

Authors: P. Jiang, Y. Katsumura, M. Domae, K. Ishikawa, R. Nagaishi, K. Ishigure

In the pulse radiolysis of concentrated phosphoric acid solutions, the direct action of radiation on phosphoric acid gives rise to the phosphate radical. The yields of the phosphate radical and the hydroxyl radical are proportional, respectively, to the electron fractions of phosphoric acid and water, and can be quantified as G(‘0H +H2PO’,) = 0.30fw+0.33,pmol J-‘. The forward and reverse rate constants of the equilibrium ‘OH +H,PO, eH20+H2PO’, were evaluated as 4.2 x lo4and 2.5 x lo3 dm3 mol-‘ s-‘ respectively, from which E0(H2P0’,, H+/H,PO,) = 2.65V was derived. The decay kinetics and the reactions of the phosphate radical have also been studied.

http://dx.doi.org/10.1039/ft9928803319