Edds trisodium salt solution

Triclopyr (98% purity), EDDS trisodium salt solution (~ 35% in H2O) and analytical grade Fe(ClO4)3 were purchased from Sigma-Aldrich. Na2SO4 (99.9% purity) was purchased from Merck. Analytical grade H2SO4, NaCl and NaOH were supplied by Panreac. An acidic solution of Ti(IV) oxysulfate (Panreac) was used for H2O2 determination. L-ascorbic acid (99% purity)
and 1,10-phenanthroline monohydrate (99% purity) employed for the analysis of soluble iron were purchased from Sigma-Aldrich and Alfa-Aesar, respectively. Active chlorine was determined by reaction with N,N-diethyl-p-phenylenediamine (1:1) oxalate (99% purity)
provided by Acros Organics. Organic solvents of HPLC or analytical grade and other chemicals used, including analytical standards of carboxylic acids, were supplied by Panreac. Ultrapure
Milli-Q water (> 18.2 MΩ cm) was employed for the preparation of synthetic and analytical solutions. The combination of Fe(ClO4)3 and EDDS, both at a concentration of 0.03, 0.06 or 0.09 mM, gave rise to the corresponding Fe(III)-EDDS (1:1) complexes in solution, following the methodology described in earlier work (Ye et al. 2019a ).

Fluoxetine hydrochloride (certified reference material) was purchased from Sigma-Aldrich.
Sodium sulfate, heptahydrated iron(II) sulfate, sulfuric acid (96-98% solution) and sodium hydroxide pellets were of analytical grade from Merck, Panreac and J.T. Baker. Fe(ClO4)3 and EDDS trisodium salt solution (~ 35% aqueous solution) used to prepare the catalytic complex were purchased from Sigma-Aldrich. TiOSO4 and 1,10-phenanthroline monohydrate employed for H2O2 and dissolved iron quantification, respectively, were from Sigma-Aldrich and Alfa Aesar. All the other chemicals were of analytical or HPLC grade supplied by Merck and Panreac.