Dimethyl disulfide CAS#624-92-0
High Purity (≥99%) – Industrial-grade quality for precise applications.
Versatile Catalyst Activator – Essential for petroleum refining (hydrotreating catalysts).
Effective Soil Fumigant – Controls nematodes/fungi, replacing methyl bromide.
Critical Chemical Intermediate – Key for flavors, fragrances, and pharmaceuticals.
Thermal Stability – Stable up to 300°C (decomposes only with strong oxidizers).
Dimethyl disulfide (DMDS) is an industrial-grade chemical with a purity level of at least 99%. This flammable yellow liquid possesses a characteristic sulfur odor. It has a melting point of -84.7°C and boils at 109.6°C. The compound exhibits a vapor pressure of 3.0×10⁶ mPa at 20°C and an octanol-water partition coefficient (log P) of 1.91. Its Henry's law constant is calculated as 105 Pa·m³/mol. With a relative density of 1.062 (measured at 20°C), it demonstrates water solubility of 2.7 g/L at the same temperature and is completely miscible with most organic solvents between 15-25°C. The substance remains thermally stable up to 300°C but becomes unstable when heated with oxidizing agents. Its freezing point is recorded at 16°C.
Dimethyl Disulfide (DMDS) (CH₃SSCH₃, CAS 624-92-0) is a high-purity (≥99%) industrial organosulfur compound. This flammable yellow liquid exhibits a characteristic pungent sulfur odor (odor threshold: 0.002-0.016 ppm). Key physical parameters include:
Melting Point: -84.7°C
Boiling Point: 109.6°C
Vapor Pressure: 3.0×10⁶ mPa (22.5 mmHg) @20°C
log P (octanol-water): 1.91
Henry's Law Constant: 105 Pa·m³/mol
Relative Density: 1.062 @20°C (water=1)
Water Solubility: 2.7 g/L @20°C
Freezing Point: 16°C (Note: Distinct from melting point due to supercooling)
Advanced Physicochemical Properties
Parameter | Value/Range |
Flash Point | 15°C (CC) |
Autoignition Temp. | 300°C |
Refractive Index | 1.525 @20°C |
Viscosity | 0.6 cP @25°C |
Dielectric Constant | 9.5 @20°C |
Heat of Combustion | -2,890 kJ/mol |
Industrial Grades & Specifications
Grade | Purity | Key Impurities | Special Features |
Refinery Grade | 99.5% | Sulfides <0.3% | Low metals (Fe<1ppm) |
Agrochemical | 98.0% | Water <0.1% | Stabilized formulation |
Electronic | 99.99% | Halogens <0.5ppm | Sub-ppb metal traces |
Food Grade | FCC-V | DMTS <0.01% | Odor-masked |
Primary Applications
1. Petroleum Refining
Sulfiding Agent: Activates hydrotreating catalysts (CoMo/Al₂O₃)
Dosage: 2-5% of catalyst weight
Reaction:
MoO3+2 DMDS→MoS2+2 H2O+2 CO2+hydrocarbonsMoOX3+2DMDSMoSX2+2HX2O+2COX2+hydrocarbons
2. Agricultural Fumigation
Soil Disinfestation:
Targets nematodes/fungi (e.g., Meloidogyne, Fusarium)
Application: 100-400 L/ha (shank-injected)
Post-Harvest Treatment: Replaces methyl bromide for stored grains
3. Chemical Synthesis
Flavor/Fragrance Intermediate:
Precursor to methanethiol (CH₃SH)
Used in onion/cheese flavorings (FEMA 3536)
Pharmaceutical Building Block: Sulfur donor for antibiotics
4. Specialty Applications
Gold Extraction: Lixiviant for refractory ores
Polymer Modification: Crosslinking agent for rubbers
Gas Odorant: Trace addition to natural gas (secondary)
Packaging & Handling
Format | Specifications | Safety Measures |
Drums | 200L UN1A1 steel (UN2381) | Grounding straps required |
IBCs | 1,000L stainless steel (X-resistant) | Inert gas padding (N₂) |
ISO Tanks | 20,000L (vapor return systems) | Pressure relief valves |
Storage: <25°C in flammable liquid cabinet (ventilated) | ||
Shelf Life: 24 months (under nitrogen) |
