Abstract: Tin ions are provided to the electrolyte-containing cathode compartment of an electrolysis cell in which the anode and cathode compartments are separated by a cationic permselective membrane. The anolyte is generally a mineral acid or tin salt thereof. Operation of the electrolysis cell results in the deposition of tin in a purified form onto the catode which may be recovered as tin metal. Alternatively, the deposited tin and cathode compartment can be washed and the cathode compartment filled with an acid solution. Reversal of the current polarity results in the production of tin salts which may be recovered. Tin salts may also be concurrently anodically produced while tin metal is cathodically electrowinned.

Abstract: Tin salts, such as, for example, alkali metal stannates, are produced by contacting at elevated temperatures an aqueous alkaline solution, such as for example, alkali metal hydroxide solutions, with a tin-containing material in the presence of a reaction promotor comprising the combination of activated carbon and an oxygen supplying agent.

Abstract: A mixture of stannic and chloride ions having a chloride to tin ratio of at least 4:1 (e.g., stannic anion complexes) is provided to the cathode compartment of an electrolysis cell in which the anode and cathode compartments are separated by a cationic permselective membrane. The anolyte is a mineral acid or tin salt thereof. Operation of the electrolysis cell results in the production of stannous anion complexes which may be treated to obtain stannous chloride products.