Proxan sodium
[CAS# 140-93-2]

Identification

• Classification: Organic raw materials >> Organic sulfur compound
• Name: Proxan sodium
• Synonyms: Sodium o-isopropyl dithiocarbonate; Sodium isopropylxanthate; Isopropylxanthic acid sodium salt
• Molecular Formula: C₄H₇NaOS₂
• Molecular Weight: 158.21
• CAS Registry Number: 140-93-2
• EC Number: 205-443-5
• SMILES: CC(C)OC(=S)[S-].[Na+]

Safety Data

• Hazard Symbols: GHS02;GHS05;GHS07;GHS08;GHS09 Danger
• Risk Statements: H228-H251-H302-H314-H315-H317-H318-H361d-H373-H411-H412
• Safety Statements: P203-P210-P235-P240-P241-P260-P261-P264-P264+P265-P270-P272-P273-P280-P301+P317-P301+P330+P331-P302+P352-P302+P361+P354-P304+P340-P305+P354+P338-P316-P317-P318-P319-P321-P330-P332+P317-P333+P317-P362+P364-P363-P370+P378-P391-P405-P407-P410-P413-P420-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Acute toxicity	Acute Tox.	4	H302
Chronic hazardous to the aquatic environment	Aquatic Chronic	2	H411
Skin irritation	Skin Irrit.	2	H315
Self-heating substances or mixtures	Self-heat.	1	H251
Serious eye damage	Eye Dam.	1	H318
Skin corrosion	Skin Corr.	1	H314
Flammable solids	Flam. Sol.	2	H228
Specific target organ toxicity - repeated exposure	STOT RE	2	H373
Reproductive toxicity	Repr.	2	H361d
Skin sensitization	Skin Sens.	1	H317
Chronic hazardous to the aquatic environment	Aquatic Chronic	3	H412
Self-heating substances or mixtures	Self-heat.	2	H252

Discovery and Applications

Proxan sodium, also known as sodium isopropyl xanthate (SIPX), is an organosulfur compound with the chemical formula C₄H₇NaOS₂. It is a pale yellow powder or pellet that is highly soluble in water. citeturn0search0

The compound was developed in the early 20th century as part of the xanthate family, which were introduced as flotation agents in the mining industry. Xanthates, including SIPX, have been instrumental in enhancing the efficiency of mineral extraction processes. citeturn0search2

The primary application of Proxan sodium is in the mining industry, where it serves as a collector in the froth flotation process. In this context, it is used to separate valuable metal sulfide ores, such as copper, lead, and zinc, from their associated gangue materials. By adsorbing onto the surface of sulfide mineral particles, Proxan sodium renders them hydrophobic, allowing them to attach to air bubbles and rise to the surface for collection. This selective affinity significantly improves the efficiency and effectiveness of the flotation process. citeturn0search2

In addition to its role in mineral processing, Proxan sodium has been utilized as a precipitant in hydrometallurgical operations. It reacts with certain metal ions in solution to form insoluble metal xanthate complexes, facilitating the removal of these metals from aqueous environments. This application is particularly valuable in the purification and recovery of metals from leach solutions. citeturn0search8

Furthermore, Proxan sodium has found use as an accelerator in the vulcanization of rubber. In this capacity, it enhances the cross-linking process between sulfur and rubber polymers, resulting in improved elasticity, strength, and durability of the final rubber product. citeturn0search8

Safety considerations are paramount when handling Proxan sodium. The compound can decompose to release carbon disulfide, a flammable and toxic gas. Therefore, appropriate safety measures, including proper storage, handling, and personal protective equipment, are essential to mitigate potential health and environmental risks. citeturn0search8

In summary, Proxan sodium is a versatile chemical agent with well-established applications in mineral processing, hydrometallurgy, and rubber manufacturing. Its development has significantly contributed to advancements in these industries, particularly in the efficient extraction of valuable metals and the production of high-quality rubber products.

References

2024. Beneficiation of Complex Zinc-Lead Ores from Görgü (Malatya, Turkey) Region by Selective Flotation. Mining, Metallurgy & Exploration, 41(6).
DOI: 10.1007/s42461-024-01156-2

2024. Performance and mechanism of NiO/La-KTaO3 composite photocatalysts for UV degradation of isoamyl xanthate in synthetic flotation wastewater. International Journal of Environmental Science and Technology, 21(17).
DOI: 10.1007/s13762-024-06180-9

2023. The role of temperature on collector adsorption in galena flotation: Implications of seasonal temperature and climate change. MRS Advances, 8(22).
DOI: 10.1557/s43580-023-00751-7