An ATR-FTIR Study of Glyphosate and Its Fe(III) Complex in Aqueous Solution

B. C. BARJA; M. DOS SANTOS AFONSO

ENVIRONMENTAL SCIENCE & TECHNOLOGY

Año: 1998 vol. 32 p. 3331 - 3335

0013-936X

An ATR-FTIR study of the vibrational spectrum of glyphosate ( N-phosphonomethylglycine) in aqueous solution 1 M in NaCl is reported. Band assignments are given in the 1800-850cm-1 range based on the analysis of the spectral changes from low to high pH values (2-11). Potentiometric titrations of glyphosate are performed at 0.1, 0.5, and 1 M ionic strengths in NaCl and the p Ka2, p Ka3, and p Ka4 values determined. A chemometric analysis of the spectral data has been carried out to support the assignments and reproduce the p Ka values. In addition, the ATR-FTIR spectrum of the 1:1 Fe(III)/glyphosate complex in aqueous solution is analyzed by comparison with that of the free ligand.-FTIR study of the vibrational spectrum of glyphosate ( N-phosphonomethylglycine) in aqueous solution 1 M in NaCl is reported. Band assignments are given in the 1800-850cm-1 range based on the analysis of the spectral changes from low to high pH values (2-11). Potentiometric titrations of glyphosate are performed at 0.1, 0.5, and 1 M ionic strengths in NaCl and the p Ka2, p Ka3, and p Ka4 values determined. A chemometric analysis of the spectral data has been carried out to support the assignments and reproduce the p Ka values. In addition, the ATR-FTIR spectrum of the 1:1 Fe(III)/glyphosate complex in aqueous solution is analyzed by comparison with that of the free ligand.-850cm-1 range based on the analysis of the spectral changes from low to high pH values (2-11). Potentiometric titrations of glyphosate are performed at 0.1, 0.5, and 1 M ionic strengths in NaCl and the p Ka2, p Ka3, and p Ka4 values determined. A chemometric analysis of the spectral data has been carried out to support the assignments and reproduce the p Ka values. In addition, the ATR-FTIR spectrum of the 1:1 Fe(III)/glyphosate complex in aqueous solution is analyzed by comparison with that of the free ligand.-11). Potentiometric titrations of glyphosate are performed at 0.1, 0.5, and 1 M ionic strengths in NaCl and the p Ka2, p Ka3, and p Ka4 values determined. A chemometric analysis of the spectral data has been carried out to support the assignments and reproduce the p Ka values. In addition, the ATR-FTIR spectrum of the 1:1 Fe(III)/glyphosate complex in aqueous solution is analyzed by comparison with that of the free ligand.a2, p Ka3, and p Ka4 values determined. A chemometric analysis of the spectral data has been carried out to support the assignments and reproduce the p Ka values. In addition, the ATR-FTIR spectrum of the 1:1 Fe(III)/glyphosate complex in aqueous solution is analyzed by comparison with that of the free ligand.a values. In addition, the ATR-FTIR spectrum of the 1:1 Fe(III)/glyphosate complex in aqueous solution is analyzed by comparison with that of the free ligand.