NITRILOTRI(METHYLENEPHOSPHONIC) ACID AS E XTRACTANT OF MINOR ELEMENTSIN SOILS

The purpose of this investigation was the evaluation of nitrilotri(met hylenephosphonic) acid (NTMP) as simultaneous extractant of Cu, Zn, Mn and Fe from sandy soils from Medanos, Buenos Aires Province, Argentin a and a comparison with he extracting ability of nitrilotriacetic acid (NTA). The studies were carried out using two different concentration s of the chelating agents at different pH values in the range 5.0-9.0. The extracted elements were determined using atomic absorption spectr ophotometry. Using 10(-3)M concentration of chelating agent, NTMP show ed as a good simultaneous extractant over all the pH range studied, wh ile NTA showed this behaviour only for Mn ion. At 3x10(-2) M concentra tion the amounts extracted by NTMP and NTA were similar with the excep tion of Fe, where the amounts extracted using NTMP were higher.