Removal of stannic chloride

A process for removing stannic chloride from solutions thereof in organic solvent-based waste streams, wherein the solvent is benzene mono-or disubstituted with C.sub.1 -C.sub.3 alkyl, chloro, bromo, C.sub.1 -C.sub.2 alkoxy or nitro;

• benzene monosubstituted with C.sub.1 -C.sub.5 alkoxycarbonyl, benzyloxycarbonyl, phenoxycarbonyl or acetyl;
• C.sub.1 -C.sub.5 alkanol;
• C.sub.1 -C.sub.4 alkane monosubstituted with C.sub.2 -C.sub.5 alkanoyl, nitro or C.sub.2 -C.sub.3 alkanoyloxy;
• acetonitrile;
• or C.sub.5 -C.sub.8 cycloalkanone;
• mixtures of said solvents;
• or a mixture of one or more of said solvents with a minor amount of a C.sub.5 -C.sub.10 alkane;
• which process comprises adding to the waste stream from about 2 to about 4 moles of dimethyl sulfoxide per mole of stannic chloride, and separating the resulting precipitate of dimethyl sulfoxide-stannic chloride complex from the waste stream.