The chemistry of the mixed solvent extractants, dibutyl-N, N-diethylcarbamoylmethylphosphonate (DBDECMP)-tri -£-butyl phosphate (TBP), using carbon tetrachloride diluent, was studied for extracting americium (III) from nitric acid at various concentrations and temperatures. Synergistic extraction of americium was observed and an extraction mechanism is proposed based on slope analysis, infrared studies, and temperature variation studies. Similar studies were performed with dibutyl-N, N-diethylcarbamoylphosphonate (DBDECP)