The formation of indoaniline dye on silver and copper-silver hydrosol particles

The influence of the composition of copper-silver hydrosol particles on the kinetics of heterogeneous formation of indoaniline dye was studied. The ra te constant for the reaction first-order in N-ethyl-N-beta-hydroxyethyl-p-p henylenediamine (TsPV-2) was found to decrease as the content of Cu in sol particles increased to 12 at. %. The observed dependence of the apparent ac tivation energy of the reaction on solution pH was explained in terms of a reaction scheme with the rate-determining step of the formation of a semiqu inone radical in the oxidation of TsPV-2. The effective electron density, t he coefficient of plasma oscillations of damping, and other parameters of s ol particles were determined based on a theoretical analysis of the absorpt ion spectra of sols. Changes in these parameters during the reaction were r ecorded. The observed kinetic parameter variations depending on the composi tion of particles were explained by changes in particle electronic characte ristics.