Sodium dimethyldithiocarbamate
[CAS# 128-04-1]

Identification

• Classification: Organic raw materials >> Organometallic compound >> Organic sodium
• Name: Sodium dimethyldithiocarbamate
• Synonyms: Dimethyldithiocarbamic acid sodium salt
• Molecular Formula: C₃H₆NNaS₂
• Molecular Weight: 143.20
• CAS Registry Number: 128-04-1
• EC Number: 204-876-7
• SMILES: CN(C)C(=S)[S-].[Na+]

Properties

• Density: 1.17 g/mL
• Melting point: 120 °C (Decomposes) (Expl.)

Safety Data

• Hazard Symbols: GHS07;GHS09 Warning
• Risk Statements: H332-H400-H410-H411
• Safety Statements: P261-P271-P273-P304+P340-P317-P391-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Acute hazardous to the aquatic environment	Aquatic Acute	1	H400
Chronic hazardous to the aquatic environment	Aquatic Chronic	1	H410
Chronic hazardous to the aquatic environment	Aquatic Chronic	2	H411
Acute toxicity	Acute Tox.	4	H332
Acute toxicity	Acute Tox.	4	H302
Specific target organ toxicity - single exposure	STOT SE	3	H335
Serious eye damage	Eye Dam.	1	H318
Skin irritation	Skin Irrit.	2	H315
Specific target organ toxicity - single exposure	STOT SE	1	H370

Discovery and Applications

Sodium dimethyldithiocarbamate, with the chemical formula C₃H₆NS₂Na, is the sodium salt of dimethyldithiocarbamic acid and belongs to the class of organosulfur compounds known as dithiocarbamates. It is typically encountered as a white to pale yellow crystalline solid that is soluble in water and polar organic solvents. The compound is known for its strong nucleophilicity and chelating ability due to the presence of two sulfur atoms in the dithiocarbamate group, which enables it to bind effectively to various metal ions. Sodium dimethyldithiocarbamate has been widely used in diverse fields, including industrial chemistry, agriculture, water treatment, and analytical applications.

The compound was first synthesized in the early 20th century during research into the reactivity of carbon disulfide with amines in the presence of alkali. The standard method of preparation involves the reaction of dimethylamine with carbon disulfide in an aqueous sodium hydroxide solution, leading to the formation of sodium dimethyldithiocarbamate. The reaction proceeds at low temperatures and results in high yields of the sodium salt, which can be isolated by crystallization or precipitation techniques.

In industrial applications, sodium dimethyldithiocarbamate has been used as a flotation agent in the mining industry. It serves as a selective collector for heavy metal sulfides, including copper, lead, and zinc ores, by forming stable metal-dithiocarbamate complexes on the mineral surfaces. These complexes increase the hydrophobicity of the mineral particles, allowing them to be separated from gangue materials in froth flotation processes. The efficiency and selectivity of the compound in this role have been confirmed through industrial-scale operations and laboratory studies.

In agriculture, sodium dimethyldithiocarbamate and its derivatives have been employed as fungicides and bactericides. They function by interfering with essential enzymatic pathways in target organisms through chelation of metal ions, which are critical cofactors in microbial metabolism. These compounds have shown broad-spectrum activity against fungal pathogens affecting crops, although their use is subject to strict regulation due to environmental persistence and potential toxicity. Application methods and permissible limits are defined by national and international safety standards.

One of the most significant applications of sodium dimethyldithiocarbamate is in environmental and industrial wastewater treatment. It acts as a heavy metal precipitant, particularly effective in the removal of mercury, cadmium, copper, and lead from wastewater streams. By reacting with dissolved metal ions, it forms insoluble metal-dithiocarbamate complexes that can be removed by filtration or sedimentation. This treatment method is widely used in industries such as electroplating, battery manufacturing, and metal finishing, where the discharge of toxic metals must be minimized to comply with environmental regulations.

In analytical chemistry, sodium dimethyldithiocarbamate serves as a sensitive reagent for detecting trace amounts of metals. It forms colored complexes with various metal ions, which can be measured spectrophotometrically. These complexes are often used for quantitative determination of metals in biological, environmental, and industrial samples. The high specificity and low detection limits offered by the compound have made it a standard reagent in analytical protocols.

The compound has also been investigated for its ability to form stable complexes with transition metals, making it a valuable ligand in coordination chemistry. It can coordinate through both sulfur atoms to form chelate complexes with geometries that depend on the metal center. These complexes have been studied for their magnetic, catalytic, and electrochemical properties. Some of them have been tested for antimicrobial and anticancer activity in vitro, although such uses are secondary to the well-established chemical and industrial applications of the parent compound.

Sodium dimethyldithiocarbamate is relatively stable under ambient conditions but may degrade upon prolonged exposure to moisture or acidic environments. In acidic solutions, it decomposes to release dimethylamine and carbon disulfide, the latter being a volatile and toxic compound. Therefore, appropriate safety measures are essential during handling and storage. The compound should be stored in tightly sealed containers under cool and dry conditions to maintain stability.

The versatility of sodium dimethyldithiocarbamate lies in its strong affinity for metal ions, which underpins its wide use in metal recovery, analytical detection, environmental remediation, and industrial processing. Its properties and applications have been comprehensively studied and documented, making it a reliable and valuable compound in numerous scientific and technical domains.

References

1947. Recent spray tests for control of potato late blight in sub-tropical Florida. American Journal of Potato Research, 24(9).
DOI: 10.1007/bf02886759

2020. Removal of Heavy Metal Ions from Water and Wastewaters by Sulfur-Containing Precipitation Agents. Water, Air, & Soil Pollution, 231(10).
DOI: 10.1007/s11270-020-04863-w

2024. Extraction of heavy metals from water using chelating agents: a comprehensive review. International Journal of Environmental Science and Technology, 21(12).
DOI: 10.1007/s13762-024-05586-9