DETERMINATION OF MICRO-AMOUNTS OF LANTHANOIDS IN CAST-IRON AFTER SOLID-LIQUID EXTRACTION WITH DIETHYLDITHIOCARBAMATE

A solid-liquid extraction separation was developed for the determinati on of total amounts of lanthanoids in cast iron. Various complexing ag ents and solid solvents were examined. It was found that diethyldithio carbamate could quantitatively extract iron and other heavy metals int o paraffin. The optimum conditions were achieved. Interferences from d iverse ions were evaluated. After separation, subsequent spectrophotom etric determination of the lanthanoids was carried out. The complexing agents and solid solvents, once used, could be recycled and used repe atedly for further separations.