Name | Thiourea |
Synonyms | THU THIO Thiurea Thiourea sulourea SULFOUREA sulfouren sulphourea 2-Thiourea Isothiourea Thiourea(TU) thio arbamid Thiocarbamide THIOCARBAMIDE sulfocarbamide THIOUREA DIOXID AKOS BBS-00004390 carbamoylsulfamic acid Thiourea, reagent grade, ACS |
CAS | 62-56-6 |
EINECS | 200-543-5 |
InChI | InChI=1/CH4N2O4S/c2-1(4)3-8(5,6)7/h(H3,2,3,4)(H,5,6,7) |
InChIKey | UMGDCJDMYOKAJW-UHFFFAOYSA-N |
Molecular Formula | CH4N2S |
Molar Mass | 76.12 |
Density | 1.405 |
Melting Point | 170-176 °C (lit.) |
Boling Point | 263.89°C (estimate) |
Water Solubility | 13.6 g/100 mL (20 ºC) |
Solubility | water: soluble137g/L at 20°C |
Appearance | Crystals |
Specific Gravity | 1.406 |
Color | White to almost white |
Odor | Odorless |
Merck | 14,9367 |
BRN | 605327 |
pKa | -1.0(at 25℃) |
PH | 6-8 (50g/l, H2O, 20℃) |
Storage Condition | Store below +30°C. |
Stability | Stable. Incompatible with strong acids, strong bases, strong oxidizing agents, metallic salts, proteins, hydrocarbons. May react violently with acrolein. |
Refractive Index | 1.5300 (estimate) |
Physical and Chemical Properties | White or light yellow, lustrous, columnar or needle-like crystals with bitter taste |
Use | Used in the manufacture of sulfonamides, dyes, resins, compression molding powder, etc., also used as rubber vulcanization accelerator, metal mineral flotation agent |
Risk Codes | R22 - Harmful if swallowed R40 - Limited evidence of a carcinogenic effect R51/53 - Toxic to aquatic organisms, may cause long-term adverse effects in the aquatic environment. R63 - Possible risk of harm to the unborn child R43 - May cause sensitization by skin contact R38 - Irritating to the skin |
Safety Description | S36/37 - Wear suitable protective clothing and gloves. S61 - Avoid release to the environment. Refer to special instructions / safety data sheets. |
UN IDs | UN 2811 6.1/PG 3 |
WGK Germany | 2 |
RTECS | YU2800000 |
TSCA | Yes |
HS Code | 29309070 |
Hazard Class | 6.1 |
Packing Group | III |
Toxicity | LD50 orally in wild Norway rats: 1830 mg/kg (Dieke) |
White and glossy crystals. Bitter in taste. Density 1.405. The melting point was 180-182 °c. Decomposition is more hot. Soluble in water, heat can be soluble in ethanol, very slightly soluble in ether. During melting, the isomerization occurs partially to form ammonium thiocyanate. It is used as a raw material for producing drugs, dyes, resins, compression molding powder, and the like, and is also used as a rubber vulcanization accelerator, a metal mineral flotation agent, and the like. It is formed by the action of hydrogen sulfide and lime slurry to form calcium hydrosulfide, and then to react with cyanamide (based) calcium. It can also be prepared by melting ammonium thiocyanate, or by the action of cyanamide and hydrogen sulfide.
colorless or white crystal or crystalline powder. Bitter in taste. Soluble in 11 parts of water, soluble in ethanol, almost insoluble in ether. Under vacuum, sublimation was performed at 150-160 °c. Flammable in case of open flame and high heat. A strong reaction with an oxidizing agent can occur. Thermal decomposition, release of nitrogen, sulfur oxides and other toxic gases.
under negative pressure and cooling, the milk of lime is used to absorb hydrogen sulfide to generate a calcium hydrosulfide solution, and calcium hydrosulfide reacts with calcium cyanamide to obtain a thiourea solution. After filtration, concentration, cooling crystallization, drying, pure thiourea.
category toxic substances
High toxicity grade
Acute oral toxicity-rat LD50: 125 mg/kg; Abdominal cavity-mouse LD50: 100 mg/kg
Irritation data eye-rabbit 14% moderate
Flammability hazard characteristics toxic sulfur oxide and nitrogen oxide gases emitted by heat
Storage and Transportation characteristics the warehouse was ventilated and dried at low temperature; Storage and transportation were separated from food raw materials
Extinguishing agent water, carbon dioxide, sand, foam
Analytical reagents. For bismuth, osmium, rhodium, selenium, lead, tellurium, nitrite, etc. Complexation indicator for determination of osmium.
wild Norwegian rat oral LD50: 1.83/kg. Inhalation of this product dust on the upper respiratory tract irritation, chest discomfort, such as Cough. Eye irritation. The product repeated action can inhibit the thyroid and hematopoietic organs. May cause allergic reactions. Store in a cool, ventilated warehouse. Keep away from fire and heat source. Protection from direct sunlight. Keep the container sealed. Should be stored separately from the oxidant, acid, alkali.
The preparation method is to react barium sulfide with sulfuric acid or hydrochloric acid, and the hydrogen sulfide gas is absorbed by milk of lime under negative pressure to obtain hydrogen sulfide calcium solution, and then react with calcium cyanamide, the molar ratio of calcium hydrosulfide to calcium cyanamide is 1 ∶ 5. Under constant stirring, the reaction temperature is (80±5)℃, the reaction time is 3H, and thiourea liquid can be generated by negative pressure filtration, after evaporation, filtration, cooling and crystallization, the Crystal thiourea is obtained, and the finished product is obtained by centrifugal dehydration and drying. Reaction equations such as: BaS H2SO4 & rarr;BaSO4 ↓ H2S & uarr;
2H2S Ca(OH)2→Ca(SH)2 2H2O
pH indicator color change ph range | 5-7 |
NIST chemical information | Information provided by: webbook.nist.gov (external link) |
(IARC) carcinogen classification | 3 (Vol. Sup 7,79) 2001 |
EPA chemical information | Information provided by: ofmpub.epa.gov (external link) |
use | thiourea is the main raw material for producing thiourea dioxide. In medicine (sulfathiazole, methyl thiouracil, tetrazolemide, nidazolemide, fluorouracil), pesticides (insecticide, sterilization, acaricide, weeding, virus control, etc.), chemical fertilizers (nitrogen fertilizer synergist), silk industry, agriculture, metal beneficiation, etc. used for the manufacture of sulfonamide drugs, dyes, resins, compression molding powder, etc., also used as rubber vulcanization accelerator, metal mineral flotation agent, etc. used as analytical reagents, complexation indicators and chromatography analysis reagents used as intermediates in the production of drugs in medicine. Used as a vulcanization accelerator in the rubber industry. Used as a flotation agent in the mining industry. Also used as fabric, paper treatment agent, printing and dyeing auxiliaries. Thiourea is an intermediate of fungicide dressing, herbicide acetochlor, tezaojin, etc. It is also the raw material of medicine thiamine thiazole, and can be used as a raw material for dyes, resins, and compression plastic powder. It can also be used as rubber vulcanization accelerator, metal mineral flotation agent, etc. This product is used to synthesize the raw materials of drugs such as sulfathiazole, methionine and fat pig tablets. Used as a raw material for dyes and dyeing auxiliaries, resins and compression molding powders. It can also be used as a vulcanization accelerator for rubber, a flotation agent for metal minerals, a catalyst for the production of phthalic anhydride and fumaric acid, and as an anti-corrosion agent for metals. In terms of photographic materials, it can be used as a developer and toner. It can also be used in electroplating industry. Thiourea is also used in diazo photosensitive paper, synthetic resin coatings, anion exchange resins, germination accelerators, fungicides and many other aspects. Thiourea is also used as a fertilizer. Strong denaturing agent, increase the solubility and recovery rate of protein Reducing agent. Precipitants for lead, thallium and cadmium. Verification and determination of bismuth, hunger, ruthenium, selenium, lead, tellurium, palladium and selenite. Organic synthesis, preparation of mercaptans from haloalkanes. |
production method | use lime milk to absorb hydrogen sulfide under negative pressure and cooling to generate calcium hydrosulfide solution. Calcium hydrosulfide and calcium cyanamide (lime nitrogen) are reacted at a molar ratio of 1:5 at about 80 ℃ for 3h to obtain thiourea solution, which is filtered, concentrated, cooled and crystallized, filtered and dried to obtain finished thiourea. In addition, it can also be prepared by ammonium thiocyanate method and diazomethane method. The preparation method is to react barium sulfide with sulfuric acid or hydrochloric acid, and hydrogen sulfide gas is absorbed by lime milk under negative pressure to prepare hydrogen sulfide calcium solution, and then react with calcium cyanamide. The molar ratio of calcium hydrosulfide to calcium cyanamide is 1:5. Under continuous stirring, the reaction temperature is (80±5)℃, and the reaction time is 3h. After negative pressure filtration, thiourea liquid can be generated, and then evaporated, filtered, cooled, and crystallized, the crystalline thiourea is obtained, and the finished product is obtained by centrifugal dehydration and drying. The reaction equation is as follows: BaS H2SO4 → BaSO4 ↓ H2S ↑ 2H2S Ca(OH)2 → Ca(SH)2 2H2O The synthesis method uses barium sulfide to react with hydrochloric acid (or sulfuric acid), uses lime milk to absorb under negative pressure, and then reacts with lime nitrogen. After filtration, cooling crystallization, centrifugal separation and drying, the finished product of thiourea is prepared. Its BaS 2HCl → BaC12 H2S ↑ CaO H2O → Ca(OH)2Ca(OH)2 2H2S → Ca(SH)2 2H2O2CaCN2 Ca(SH)2 6H2O → 2(NH2)2CS 3Ca(OH)2 |
category | toxic substances |
toxicity classification | highly toxic |
acute toxicity | oral administration-rat LD50: 125 mg/kg; Abdominal cavity-mouse LD50: 100 mg/kg |
stimulation data | eye-rabbit 14% moderate |
flammability hazard characteristics | toxic sulfur oxide and nitrogen oxide gas released by heating |
storage and transportation characteristics | warehouse ventilation and low temperature drying; separate from food raw materials storage and transportation |
fire extinguishing agent | water, carbon dioxide, sand, foam |
spontaneous combustion temperature | 440°C Dust |
toxic substance data | information provided by: pubchem.ncbi.nlm.nih.gov (external link) |