DEGRADATION OF SULFUR-CONTAINING S-TRIAZINES DURING WATER CHLORINATION

Citation
G. Mascolo et al., DEGRADATION OF SULFUR-CONTAINING S-TRIAZINES DURING WATER CHLORINATION, Water research, 28(12), 1994, pp. 2499-2506
Citations number
33
Categorie Soggetti
Engineering, Civil","Environmental Sciences","Water Resources
Journal title
ISSN journal
00431354
Volume
28
Issue
12
Year of publication
1994
Pages
2499 - 2506
Database
ISI
SICI code
0043-1354(1994)28:12<2499:DOSSDW>2.0.ZU;2-A
Abstract
The reactions of four sulphur containing s-triazines (prometryne, terb utryne, ametryne and desmetryne) with hypochlorous acid (HClO) and chl orine dioxide (ClO2) have been investigated using an 11 ppm/3 ppm oxid ant/herbicide ratio. The main objective of the study was the identific ation of by-products. Additionally, to study the effect of oxidant con centration on the reaction rate, two more oxidant/herbicide ratios (3 ppm/3 ppb and 11 ppb/3 ppb) have been investigated only for prometryne . Oxidation reactions were monitored by high performance liquid chroma tography (HPLC), while, the identification of by-products was initiall y carried out by low resolution HPLC-mass spectrometry (HPLC-MS) and c onfirmed by accurate mass measurement. Under the experimental conditio ns (T = 20 degrees C, pH = 8, reaction time = 48 h), the results indic ate that all the investigated triazines react in the same way with eac h oxidant. The reactions with HClO occur much faster than those with C lO2 and give rise to three identified oxidation by-products: the sulfo xide, the sulfone and the sulfone's hydrolysis product. The reactions with ClO2, instead, give rise to a sole oxidation by-product: the sulf oxide. With both oxidants, as expected, the lower the oxidant concentr ation the slower the oxidation rate. Based on the obtained results, a general pathway for the oxidation of sulphur containing s-triazines is proposed.