Reaction products of aquatic humic substances with chlorine.

Abstract

A major concern of the chlorination of aquatic humic materials is the ubiquitous production of trihalomethanes. A large number of other chlorinated organic compounds, however, have been shown to be formed by chlorine's reaction with humic substances. In this study, humic material was concentrated from a coastal North Carolina lake and chlorinated at a chlorine to carbon mole ratio of 1.5 at pH 12. A high pH was necessary for complete dissolution of the humic material and for production of adequate quantities of oxidation and chlorination products for extraction, separation and mass spectrometric identification. After concentration in ether, samples were methylated, separated with a 50-m OV-17 glass capillary column or a 25 m SP-2100 fused-silica column and identified. A Hewlett-Packard 5710A gas chromatograph interfaced to a VG Micromass 7070F double-focusing mass spectrometer was used. Low resolution, accurate mass measurements were made with a combined EI-CI source.The ability to do low resolution, accurate mass measurements made possible a rapid scan function necessary for capillary column gas chromatography. Accurate mass measurements allowed increased confidence in the identification of compounds, most of which are not available as standards. The products identified in these studies were chlorinated aliphatic straight-chain acids dominated by di-and trichloroacetic acid and the chlorinated dicarboxylic acids: succinic, fumaric and maleic acids. Chlorinated and unchlorinated aliphatic mono-and dicarboxylic acids and unchlorinated polycarboxylic aromatic acids comprise the remaining bulk of the compounds identified.

Reaction Products of Chlorine Dioxide

“…However, the classical haloform reaction is not the complete explanation because certain phenol derivatives, notably resorcinol, do react quite readily with aqueous chlorine to produce chloroform. The relationship of these reactions to those of humic materials with chlorine has been under intense investigation (21) and has been reported in part by Johnson (22). Reactions of humic materials with chlorine dioxide are discussed in more detail below.…”

Development of a nanofiltration membrane for humic acid removal through the formation of polyelectrolyte multilayers that contain nanoparticles

“…Its presence in potable water filtration systems can also contribute to the formation of hazardous materials such as trihalomethanes [2]. Nanofiltration (NF) is the preferred process for the partial removal of NOM and divalent *Corresponding author.…”

Evaluation of Chlorinated By‐Products in Drinking Waters of Clentral Friuli (Italy)

“…Its reduction leads in fact to reduced amounts of THMs, accompanied by the formation of chlorite anion which represents the typical by-product of dioxi-chlorination. Therefore, THMs and chlorites can be considered typical by-products of chlorination and dioxichlorination, respectively [3][4][5] .…”