Trisodium cyanurate

Stable A/-chloro compounds are formed by reaction of hypochlorous acid and appropriate N—H compounds. For example, HOCl, formed in situ via chlorine hydrolysis, converts di- or trisodium cyanurates to dichloro- and trichloroiso-cyanuric acids, respectively (114). Chloroisocyanurates can also be prepared from isocyanuric acid or monosodium cyanurate and preformed HOCl (115—117). Hydrolysis of chloroisocyanurates provide HOCl for use in swimming pool disinfection and in bleaching appHcations. 

The kinetics of /V-ch1orination of CA iu basic media have been studied by stopdow spectrophotometry (21). The A/-chloro derivatives are the most important commercial products derived from CA. Their av CI2 and other values appear iu Table 2. Trichloroisocyanuric acid [87-90-17, TCCA, or l,3,5-trichloro-j -tria2iQe-2,4,6(lJT,3JT,5J-i)-trione, is obtained iu - 90% yield by cblorination of aqueous trisodium cyanurate, prepared from CA and NaOH iu a 1 3 molar ratio (22). 

We are indebted for the gift of crystals of trisodium cyanuric tricyanamide to the late Professor E. C. Franklin. We wish to thank Dr. J. Sherman for assistance with the laborious quantum mechanical calculations. 

The thiocyanurates are readily hydrolyzed in acid to cyanuric acid and a thiol. Trimethyl trithiocyanurate reacts with sodium sulfide to give the trisodium salts. Melamine is formed on treatment of the thiocyanurates with aqueous ammonia at high temperatures the alkylthio groups are replaced sequentially <59HC(l3)l,p.lll), and can be removed using Raney nickel (equation 25) . 

To address this concern, several organic and inorganic reagents were evaluated as precipitants for heavy metals in a 10-34-0 (N-P2O5-K2O) fluid fertilizer and WPA. Trisodium trithiocyanuric acid (TMT-15), sodium polythiocarbonate (Thio-Red II), and sodium trithiocarbonate (5% Na2 CS3) precipitated arsenic, cadmium, copper, mercury, lead, and zinc from 10-34-0. Ammonium cyanurate was ineffective in removing cadmium from 10-34-0. Thio-Red II and 5% Na2CS3 precipitated mercury, lead, cadmium, copper, and chromium from WPA. A water-insoluble starch xanthate adsorbed mercury, copper, and lead from 10-34-0 and WPA. Sodium sulfide, sodium polysulfide, and potassium ferrocyanide were tested as inorganic precipitants. The polysulfide was twice as effective as the sulfide alone, and concentrations of less than 10 ppm of arsenic, cadmium, mercury, and lead were achieved in 10-34-0. Ferrocyanide reduced the concentrations of cadmium and nickel to less than 10 ppm in WPA. 

Sulfur-containing nucleophiles react with cyanuric chloride to form sulfanyl-substituted 1,3,5-triazines.42,96,97 In the presence of sodium hydroxide, sodium sulfide and cyanuric chloride give the trisodium salt of 1,3,5-triazine-2,4,6-trithiol (13), which is used as a scavenger of heavy metals.98,99... 

Since the trisodium salt of cyanuric acid is in the enol form, it has the band normally observed for triazines near 820cm (12.20gm) (see melamine), as do trialkyl cyanurates. 

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