Thiourea Dioxide, Formamidine Sulfinic Acid, Aminoiminomethanesulfinic Acid, TUDO, FAS, TDO 1758-73-2

Thiourea Dioxide, Formamidine Sulfinic Acid, Aminoiminomethanesulfinic Acid, TUDO, FAS, TDO 1758-73-2

THIOUREA DIOXIDE (TDO)

PRODUCT IDENTIFICATION INFORMATION

CHEMICAL STRUCTURE

Thiourea Dioxide Structure:

        O
        ||
    H₂N—C—SO₂H
        ||
        NH

Structure Description:

• Organic compound derived from thiourea (oxidized form).

• Also known as formamidine sulfinic acid.

• White, free-flowing crystalline powder.

• Odorless and stable under normal conditions.

• "Latent" or "activatable" reducing agent (becomes active upon heating or in alkaline conditions).

• Does not release toxic gases under normal storage conditions.

SECTION 1: CHEMICAL IDENTITY AND DESCRIPTION

SECTION 2: PHYSICAL AND CHEMICAL PROPERTIES

SECTION 3: THIOUREA DIOXIDE vs OTHER REDUCING AGENTS

SECTION 4: MECHANISM OF ACTION

SECTION 5: PRODUCTION PROCESS

Industrial Production Method:

Process Flow:
Thiourea → Oxidation (Hydrogen Peroxide or Electrochemical) → Thiourea Dioxide → Crystallization → Filtration → Washing → Drying → Milling → Final Product

Step-by-Step Description:

1. Raw Material: High-purity thiourea is used as the starting material.

2. Oxidation: Thiourea is oxidized using hydrogen peroxide (H₂O₂) or by electrochemical oxidation under controlled conditions.

3. Crystallization: The product is crystallized from the reaction mixture.

4. Filtration: Crystals are separated from the mother liquor.

5. Washing: Crystals are washed to remove impurities.

6. Drying: Purified crystals are dried at low temperature to achieve the specified moisture content.

7. Milling: Dried product is milled to achieve the desired particle size.

8. Final Product: Free-flowing white crystalline powder is obtained.

SECTION 6: FUNCTIONAL PROPERTIES

SECTION 7: MAIN APPLICATION AREAS

SECTION 8: SAMPLE FORMULATIONS

Discharge Printing Paste (Textile):

Process: Apply discharge paste to pre-dyed fabric; Dry; Steam at 100-105°C (heat activates TDO); TDO reduces and destroys dye; Wash and finish.

Reductive Washing Bath (Polyester):

Process: Heat bath to 80-90°C; Treat fabric for 20 minutes; Rinse thoroughly; Neutralize and finish.

Pulp Bleaching Application:

Process: Add TDO to pulp slurry; Adjust pH with alkali; Heat to activate; Bleach for specified time; Wash and process.

SECTION 9: QUALITY SPECIFICATIONS

SECTION 10: TOXICOLOGICAL PROFILE

SECTION 11: GHS CLASSIFICATION AND LABELING

GHS Classification (in accordance with CLP and UN GHS):

Signal Word: None (Not classified as hazardous)

Hazard Pictograms: None

NFPA 704 Hazard Classification:

SECTION 12: PRECAUTIONARY STATEMENTS (P-CODES)

SECTION 13: FIRST AID MEASURES

SECTION 14: FIREFIGHTING MEASURES

SECTION 15: STORAGE AND SHELF LIFE

SECTION 16: PACKAGING OPTIONS

SECTION 17: TRANSPORT INFORMATION

SECTION 18: REGULATORY STATUS

SECTION 19: OTHER NAMES AND SYNONYMS

SECTION 20: SUMMARY TABLE

SECTION 21: CRITICAL WARNINGS AND BEST PRACTICES

CRITICAL WARNINGS:

• LATENT REDUCING AGENT: Stable in dry form and cold aqueous solution; Activates upon heating (≥60°C) or in alkaline conditions.

• FORMALDEHYDE-FREE: Does not contain or release formaldehyde; Safer alternative to Rongalit.

• NON-FLAMMABLE: Stable and non-combustible under normal conditions.

• ODORLESS: No pungent or irritating odors.

• STABLE: Does not release toxic gases under normal storage conditions.

• NON-TOXIC: Low toxicity; Safe for handling with standard precautions.

• DECOMPOSITION PRODUCTS: Decomposes to urea and sulfate (relatively harmless).

• ACTIVATION REQUIRED: Not active at room temperature; Requires heat and/or alkali for reduction.

• ENVIRONMENTALLY FRIENDLY: Biodegradable; Minimal environmental impact compared to other reducing agents.

BEST PRACTICE RECOMMENDATIONS:

• Textile (Discharge Printing): Use as formaldehyde-free discharge agent; Dosage: 5-10% of paste weight; Activate with alkali (2-5% Na₂CO₃ or NaOH); Steam at 100-105°C; Effective on vat, reactive, and direct dyes.

• Textile (Reductive Washing): Use for polyester and synthetic fibers; Dosage: 1-3 g/L; Activate with NaOH (1 g/L); Process at 80-90°C for 20 minutes; Removes oxidative residues; Improves whiteness.

• Pulp & Paper: Use for bleaching and deinking; Dosage: 0.5-2% of pulp weight; Activate with alkali and heat; Improves brightness; Reduces color.

• Organic Synthesis: Use as reducing agent for organic compounds; Dosage: Stochiometric or slight excess; Activate with heat and/or alkali; Reduces ketones, nitro compounds, imines.

• Water Treatment: Use as oxygen scavenger and decolorizer; Dosage: 5-50 ppm; Removes excess oxidants; Reduces color in wastewater.

• Handling: Use in well-ventilated areas; Avoid dust formation; Use dust masks when handling powder; Use gloves and safety goggles; Avoid contact with alkalis during storage.

• Personal Protective Equipment: Dust mask (N95/FFP2) if dust is generated, safety goggles, chemical-resistant gloves, protective clothing.

• Hygiene: Wash hands thoroughly after handling; Do not eat, drink, or smoke while using; Remove contaminated clothing and wash before reuse.

• Storage: Store in tightly closed, moisture-proof containers; Store in cool, dry, well-ventilated area; Protect from moisture and heat; Keep away from alkalis and strong oxidizing agents; Opened containers must be resealed immediately; Shelf life: 24-36 months under proper conditions.

• Spill Management: Sweep or vacuum (HEPA) and place in suitable sealed container; Avoid dust formation; Do not allow entry into drains or waterways.

• Disposal: Dispose of in accordance with local, regional, and national regulations; Non-hazardous waste; Can be incinerated in compliance with regulations.

DETECTION METHODS:

THIOUREA DIOXIDE vs ALTERNATIVES COMPARISON:

LEGAL DISCLAIMER:
The information provided in this document is based on our current knowledge and experience and is presented in good faith. However, as all conditions of use are beyond our control, it does not constitute a binding specification or warranty. This Technical Data Sheet is for informational purposes only. Users are responsible for testing the suitability for their own applications and for complying with all local, regional, and national regulations. For complete safety, storage, use, handling, waste, and regulatory compliance information, please refer to the official Safety Data Sheet (SDS/MSDS) provided by the manufacturer/supplier.