Chloramines organic

Both chloramine-T and dichloramine-T have marked antiseptic properties, chloramine-T being most frequently used because of its solubility in water. Aqueous solutions of chloramine-T can be used either for external application, or for internal application to the mouth, throat, etc, as chloramine-T in moderate quantities is non-toxic its aqueous solution can also be effectively used when the skin has come in contact with many of the vesicant liquid poison-gases, as the latter are frequently organic sulphur or arsenic derivatives which combine with or are oxidised by chloramine-T and are thus rendered harmless. 

Both chloramine-T and dichloramine-T slowly liberate hypochlorous aeid in eontaet with water and are therefore employed as antiseptics the former is employed in the form of a dilute (e.g., 0-2 per eent.) aqueous solution, and the latter (which is insoluble in water) as a solution in an organic solvent, such as a chlorinated paraffin. 

SuperchlorinationShock Treatment. Superchlorination or shock treatment of pool water is necessary since accumulation of organic matter, nitrogen compounds, and algae consumes free available chlorine and impedes disinfection. Reaction of chlorine with constituents of urine or perspiration (primarily NH" 4, amino acids, creatinine, uric acid, etc) produces chloramines (N—Cl compounds) which are poor disinfectants because they do not hydrolyze significantly to HOCl (19). For example, monochloramine (NH2CI) is only 1/280 as effective as HOCl against E. coli (20). 

In reahty the chemistry of breakpoint chlorination is much more complex and has been modeled by computer (21). Conversion of NH/ to monochloramine is rapid and causes an essentially linear increase in CAC with chlorine dosage. Further addition of chlorine results in formation of unstable dichloramine which decomposes to N2 thereby causing a reduction in CAC (22). At breakpoint, the process is essentially complete, and further addition of chlorine causes an equivalent linear increase in free available chlorine. Small concentrations of combined chlorine remaining beyond breakpoint are due primarily to organic chloramines. Breakpoint occurs slightly above the theoretical C1 N ratio (1.75 vs 1.5) because of competitive oxidation of NH/ to nitrate ion. Organic matter consumes chlorine and its oxidation also increases the breakpoint chlorine demand. Cyanuric acid does not interfere with breakpoint chlorination (23). 

The concentration of inorganic and organic chloramines in pool water is controlled by superchlorination or shock treatment. Because chloramines are decomposed by sunlight, their effects are more noticeable in indoor pools or spas. Nitrogen trichloride, the primary volatile chloramine, is a strong irritant similar to chlorine. Its effect is noticeable at >0.5 mg/m (>0.1 ppm) (73). The concentration of NCl depends on the extent of ventilation and typically varies from 0.2 to 0.5 mg /m (0.04 to 0.1 ppm) (74). 

Dichloramine. The least stable chloramine, dichloramine [3400-09-7] has not been prepared in pure form. However, it has sufficient stabiUty in dilute organic or aqueous solutions for deterrnination of some physical and chemical properties. It has a pungent odor and can impart an odor or off-taste to water at concentrations above 0.8 ppm. Dichloramine can be produced by reaction of HOCl with a slight excess of NH in the pH range 4—7 or by disproportionation of NH2CI at pH 3.5—4.0 ... 

Swimming pools Ozone injection for removal of organic contaminants Removal of residual ozone and control of chloramine levels... 

Combined available chlorine The concentration of chlorine which is combined with ammonia (NH3) as chloramine or as other chloro derivatives, yet is still available to oxidize organic matter. 

A number of organic chlorine, or chloramine, compounds are now available for disinfection and antisepsis. These are the N-chloro (=N-C1) derivatives of, for example, sulphonamides giving compounds such as chloramine-T and dichloramine-T and halazone (Fig. 10.5), which may be used for the disinfection of contaminated drinking water. 

Furthermore, the photo-catalytic fiber can be used for the purification of the many types of wastewater. Figure 37 shows the result regarding a decomposition of dioxin contained in a wastewater. In this case, 95.1% of the dioxin was found to be decomposed after only 2 h. Moreover, the muddiness of the pool water was remarkably improved by the passage through the purifier (Fig. 38) along with a decrease in the organic filth and chloramines. 

With sulfonamide-derived chloramine salts bearing smaller organic substituents on the sulfur, for example, methanesulfonamide-derived chloramine salt 111 (chloramine-M) as the oxidant, better results are obtained. This reagent can be prepared separately and added to the reaction mixture as the stable anhydrous... 

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