Extraction of HNO3 by triaryl amine was studied by equilibrating equal volumes of aqueous and organic phases at 25C. At HNO3 concentrations of 2 to 10 N the acid in the organic phase in excess of that equivalent in the amine concentration was proportional to the concentration of HNO3 in the equilibrated aqueous phase. other workers report similar results with nitric acid and tri-n-octyl amine in benzene. Zirconium extractions carried out at 10g Zr/1 with 0.35 M TLA nitrate in toluene showed a fourth power dependence of EZR on HNO (aq) over the range 2 to 10N. Maximum distribution ratios calculated from samarium scouting experiments using amines in kerosene were about 5 x 10(-3) for Primene JMT, 10(-4) for TLA, 10(-5) for S-24, and less than zero for DTDA. Distribution rations in the extractions ranged from ERu = 0.12 for 0.35M TLA shaken with an initially new 2N HNO3 solution for 15 minutes. Data on Zr and Ru standardization in TLA solution for spectrophotometric analyses are included.