Synthesis of new immobilized N-chloro-sulfonamides and release of active chlorine from them

Bohdan Murashevych,Valerii Kotok,Dmytro Stepanskyi,Vadym Kovalenko,Volodymyr Toropin,Kostyantyn Burmistrov,Hanna Maslak

doi:10.21303/2461-4262.2021.001929

Abstract

A method has been developed for the synthesis of granular polymeric materials with immobilized N-chloro-sulfonamide groups. Commercially available resin polymers widely applied for the preparation of ion exchangers have been used as polymer carriers. The elaborated technological conditions make it possible to modify these resins with a high conversion degree, without deteriorating the strength characteristics, and with the possibility of regulating the concentration of active chlorine over a wide range (up to 11 % w/w). The structure of the synthesized polymers was confirmed by IR spectroscopy data. To determine the concentration of functional groups, a special method of iodometric titration has been developed. The processes of emission of active chlorine from synthesized polymers into aqueous solutions have been studied. It has been shown that this process significantly depends on the composition of the solution: no release of active chlorine into distilled water is observed, and when using tap water, its concentration is reached 5–8 mg/dm3 and remains up to 30 days when the granules are in water. The processes of activation of active chlorine emission by compounds of amine nature have been studied, the corresponding kinetic curves of the dependence between change in the concentration of active chlorine in solution and the used activator are presented. It has been found that the nature of the used activator strongly affects, among other things, the stability of the obtained chlorine-active solutions. Taurine and sulfamic acid are found to be the optimal activators for obtaining stable solutions of active chlorine of high concentration. The composition of the N-chloro-taurin solution obtained in this way has been additionally analyzed by UV spectroscopy. Thus, the synthesized polymers make it possible to quickly in situ obtain high-purity solutions of active chlorine without the use of special electrochemical equipment. The polymers themselves are compact, stable, and can be repeatedly regenerated

Highlights

Active chlorine compounds, of which sodium and calcium hypochlorites, hypochlorous acid, and various chloramines are the most famous, are known as extremely effective biocidal agents [1,2,3]
However, most part of traditional active chlorine compounds exist in the form of diluted solutions, which are unstable, corrosive, and require special storage and transportation conditions [15,16,17]
The aim of our investigation consisted in the synthesis of materials with immobilized active chlorine on polymer carriers which are specific for Ukraine and the CIS countries

Summary

Introduction

Of which sodium and calcium hypochlorites, hypochlorous acid, and various chloramines are the most famous, are known as extremely effective biocidal agents [1,2,3]. The study of the release processes of active chlorine from synthesized polymers has been carried out on samples of sodium N-chloro-sulfonamide of gel and macroporous structure with the active chlorine content of 8.7 % and 8.3 %and moisture content of 20.0 % and 22.8 %, respectively, as well as on polymer samples in H-form with the same quantitative characteristics obtained by treating said sodium N-chlorosulfonamides with hydrochloric acid. It have been tested as activators the number of ammonia derivatives and organic amines, each of which is capable of forming more or less stable N-chloramines: ammonia solution (ammonium hydroxide), ammonium chloride, KU-2–8 cation exchange resin in ammonium form, sulfamic acid, aminoacetic acid, aminocaproic acid and taurine The reactions of these compounds with immobilized N-chloro-sulfonamide groups are shown in Fig. 4 in general form.

Ammonium chloride

Findings

Conclusions