Pulse radiolytic investigation of the reduction of cadmium(II) ions

Abstract

In y-irradiated aqueous CdS04 solutions containing alcohols or formate ions, the hydrated electron reacts with Cd2+ to form Cd+ and the OH and H radicals react with the organic solute to form organic free radicals. The 100 eV yield of metallic cadmium was 2.5 in the presence of formate and close to zero in the presence of t-butanol and in the absence of organic additives. In the presence of other alcohols, the highest yield observed was with methanol [G(Cd) = 1.31 and the lowest with propan-2-01 (G = 0.4).Pulse radiolytic studies with optical absorption, conductimetric and light scattering techniques for detection of intermediates yielded the following results : Cd+ is oxidized by the radical CH2(CH&-COH. a-Alcohol r a d i d s react with Cd+ ions to form products which hydrolyse in the millisecond time scale to regenerate CdZ+. The reaction 2 Cd++Cdq+ (2k = 3 . 0 ~

Pulse Radiolysis Study of Cd EDTA2 ̄and Pb EDTA2 ̄ in Alkaline Solution in the Presence of Alcohols

“…This formation can be partly suppressed by large amounts of OH radical scavengers [27,28], The decay curve of Cd EDTA^" consists of at least two components. We attribute the fast component to reaction (6) Cd EDTA^" + H2O2 ^ Cd EDTA'" + OH + OH", (6) similar to the reaction (7) reported by MEYERSTEIN and MULAC [3] …”

Formation of Cd particles by UV laser irradiation

“…The reduction rates between Cd 2+ and e aq − , and between Cd + and Cd + are seen to be shorter than the laser pulse width. The rate constant of the reaction between Cd + and Cd + is 3.0 × 10 9 M − 1 s − 11 [6]. Subsequently, these intermediates react among each other and the Cd particle is formed via the reaction of Cd 2 2+ .…”

“…The formed e aq − reacts efficiently with the neighbouring Cd 2+ and finally the Cd + will be produced. The rate constant of the reaction of 3.5 × 10 10 M − 1 s − 1 has been determined using a pulse radiolysis [6]. Fig.…”

Mechanism of the Reduction of Lead Ions in Aqueous Solution (a Pulse Radiolysis Study)

“…The redox potentials for the atomic lead systems are induced in the figure, too. Experimentally, it has been shown that a complex is formed which finally decays to yield Cd2+ [3]. In all these calculations, the free energy of hydration of the metal atoms was assumed to be negligable.…”

“…Redox Potential ConsiderationsSome of the results obtained in Section 111.1 as well as the earlier work on Nit and Cd+[2,3] may now be discussed in terms of the standard redox potentials of the systems involved. Redox Potential ConsiderationsSome of the results obtained in Section 111.1 as well as the earlier work on Nit and Cd+[2,3] may now be discussed in terms of the standard redox potentials of the systems involved.…”