THE FORMATION OF A TIN DIOXIDE SOL DURING ELECTROLYSIS OF A TIN(IV) CHLORIDE SOLUTION

In the process of electrolysis of a SnCl4 solution, the dimensions of polymeric tin-oxygen complexes (chlorostannic acids) increase as the C l/Sn atomic ratio decreases. In these complexes, the fraction of Sn-O internal bonds with dimensions characteristic of cassiterite increases , whereas the fraction of the Sn-Cl end bonds decreases, and a sol wit h the crystalline structure of particles is formed. The colloidal part icles have a radially nonuniform structure: the core of a particle con sists of tin dioxide of the cassiterite modification, whereas the surf ace layer is composed of tin oxy- and hydroxychloride. The colloidal p rocesses of the formation of the tin dioxide sol during the electrolys is of a tin tetrachloride solution in a two-compartment electrolyzer a re similar to the processes occurring during the electrolysis of a SnC l4 solution in a three-compartment electrolyzer. The current efficienc y for chlorine during electrolysis in the two-compartment electrolyzer is higher than that in the three-compartment one.