Study on the Synthesis of Thiourea Dioxide
ABSTRACT
Thiourea dioxide(TD),as a novel reductant, has good stability and high redox potential,
and will not be spontaneous decomposed. It is very convenience and safety for transportation,
storage and utilization. Meanwhile, rongalite, which is widely used in dyeing and blenching industry, is easily decomposed and self-ignited, then cause some potential safety problems.
Hence, in foreign countries, TD has been widely used in various fields as the substitute of rongalite, such as printing and dyeing industry, bleaching industry, pHarmaceutical industry,
organic synthesis and analysis, paper making industry, polymer industry, and pHotosensitive material industry and so on.
Thiourea dioxide was synthesized by thiourea and hydrogen peroxide, sulfur dioxide by one step reaction of urea. Optimal conditions for the target product were: n (hydrogen peroxide): n (thiourea dioxide) = 2.15:1, reaction time was 75min, reaction temperature was 0 ℃ ~ 2 ℃, the solvent is a mixture of 50%water and 50%alcohol, crystallization time was 75min, the amount accelerant of acetone was 2%, the amount pH stabilizer of ammonium bicarbonate was 3%. Ratio of translation can reach at 91.32%. Fourier transform infrared spectroscopy, 1HNMR, 13CNMR of the target product was characterized, The results showed that the target product was thiourea dioxide.
KEY WORDS：thiourea, hydrogen peroxide, ammonium bicarbonate, acetone, thiourea dioxide
