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| Section2 = }} Thiourea dioxide or thiox is an organosulfur compound that is used in the textile industry.〔Klaus Fischer et al. "Textile Auxiliaries" in ''Ullmann's Encyclopedia of Industrial Chemistry'', 2002, Wiley-VCH, Weinheim. 〕 It functions as a reducing agent.〔Milne, G. W. A. Dictionary, in ''Gardner's Commercially Important Chemicals: Synonyms, Trade Names, and Properties'', John Wiley & Sons, Inc. 2005, Hoboken, NJ, USA. .〕 Thiourea dioxide is not a dioxide, but instead is a derivative of a sulfinic acid (RS(O)(OH), hence the alternative name formamidine sulfinic acid.〔 ==Synthesis== Thiourea dioxide is prepared by the oxidation of thiourea with hydrogen peroxide.〔D. Schubart "Sulfinic Acids and Derivatives" in ''Ullmann's Encyclopedia of Industrial Chemistry'', 2012, Wiley-VCH, Weinheim. 〕 :(NH2)2CS + 2H2O2 → (NH)(NH2)CSO2H + 2H2O The mechanism of the oxidation has been examined. An aqueous solution of thiourea dioxide has a pH about 6.5 at which thiourea dioxide is hydrolyzed to urea and sulfoxylic acid. It has been found that at pH values of less than 2, thiourea and hydrogen peroxide react to form a disulfide species. It is therefore convenient to keep the pH between 3 to 5 and the temperature below 10 °C. It can also be prepared by oxidation of thiourea with chlorine dioxide.〔Rábai, G., Wang, R. T. and Kustin, "Kinetics and mechanism of the oxidation of thiourea by chlorine dioxide" International Journal of Chemical Kinetics, 1993, volume 25: 53–62. .〕 The quality of the product can be assessed by titration with indigo.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Thiourea dioxide」の詳細全文を読む スポンサード リンク
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