Sodium Hexyl Xanthate, Sodium Hexyl Xanthogenate, Sodium Hexyl Dithiocarbonate, Sodium O-Hexyl Dithiocarbonate, Sodium Hexyl Dithiocarbamate, SHX, 35042-31-6
SODIUM HEXYL XANTHATE (SHX)
Product Name: Sodium Hexyl Xanthate
Other Names: Sodium Hexyl Xanthogenate, Sodium Hexyl Dithiocarbonate, Sodium O-Hexyl Dithiocarbonate, SHX, Sodium Hexyl Dithiocarbamate
CAS Number: 35042-31-6
Chemical Formula: C₆H₁₃OCS₂Na
Molecular Weight: ~188.24 g/mol
EC Number: Not assigned
Chemical Class: Xanthate (Dithiocarbonate) – Flotation Reagent
Origin: Synthetic, flotation reagent
SECTION 1: PRODUCT IDENTIFICATION AND DEFINITION
| Parameter |
Information |
| Product Name |
Sodium Hexyl Xanthate |
| Other Names |
Sodium Hexyl Xanthogenate, Sodium Hexyl Dithiocarbonate, Sodium O-Hexyl Dithiocarbonate, SHX, Sodium Hexyl Dithiocarbamate, Sodium Hexylxanthate |
| CAS Number |
35042-31-6 |
| Chemical Formula |
C₆H₁₃OCS₂Na |
| Molecular Weight |
~188.24 g/mol |
| EC Number |
Not assigned |
| Chemical Class |
Xanthate (Dithiocarbonate) – Flotation Reagent |
| Origin |
Synthetic, flotation reagent |
| Appearance |
Pale yellow to light brown powder, flakes, or pellets |
| Odor |
Characteristic pungent, unpleasant odor |
| Solubility |
Soluble in water |
| Physical Form |
Powder, flakes, or pellets depending on production method |
SECTION 2: PHYSICAL AND CHEMICAL PROPERTIES
| Property |
Value |
| Molecular Weight |
~188.24 g/mol |
| Appearance |
Pale yellow to light brown powder, flakes, or pellets |
| Odor |
Characteristic pungent odor |
| pH (1% solution) |
8 – 11 |
| Density |
~1.1 g/cm³ |
| Melting Point |
Decomposes before melting |
| Decomposition Temperature |
> 200 °C |
| Solubility |
Soluble in water |
| Stability |
Stable under recommended storage conditions |
| Hygroscopicity |
Hygroscopic (absorbs moisture from air) |
| Bulk Density |
~0.6 – 0.9 g/cm³ |
SECTION 3: SPECIFICATIONS AND QUALITY STANDARDS
| Parameter |
Value / Limit |
| Purity (Assay) |
Min. 90.0% |
| Free Alkali (as NaOH) |
Max. 0.5% |
| Moisture |
Max. 4.0% |
| Insoluble Matter |
Max. 0.5% |
| Appearance |
Uniform powder, flakes, or pellets |
| pH (1% solution) |
8 – 11 |
| Sulfide Content |
< 0.5% |
| Heavy Metals (as Pb) |
< 10 ppm |
SECTION 4: CHEMICAL STRUCTURE AND PROPERTIES
4.1. Chemical Structure
| Parameter |
Information |
| Chemical Name |
Sodium O-Hexyl Dithiocarbonate |
| IUPAC Name |
Sodium hexoxymethanedithioate |
| SMILES |
CCCCCCOC(=S)[S-].[Na+] |
| Alkyl Group |
Hexyl – C₆ (6-carbon chain) |
| Functional Group |
Dithiocarbonate (xanthate) – OCSS⁻ |
4.2. Chemical Properties
| Property |
Description |
| pH Stability |
Stable in alkaline conditions; decomposes rapidly in acidic environments (pH < 7) |
| Reaction with Metal Ions |
Forms insoluble complexes with heavy metal ions |
| Hydrolysis |
Hydrolyzes to produce xanthic acid and alcohol |
| Oxidation |
Oxidizes to dixanthogen in the presence of oxygen |
| Aqueous Stability |
Degrades over time; faster degradation in acidic conditions |
SECTION 5: MECHANISM OF ACTION IN FLOTATION
5.1. Collector Mechanism
| Mechanism |
Description |
| Adsorption |
SHX adsorbs onto the surface of sulfide minerals through chemisorption (formation of metal-xanthate complexes) |
| Hydrophobicity |
The adsorbed SHX layer makes the mineral surface hydrophobic, allowing it to attach to air bubbles |
| Long Hexyl Chain |
The 6-carbon hexyl chain provides very strong collecting power (higher hydrophobicity compared to shorter-chain xanthates) |
| Flotation |
Hydrophobic mineral particles attach to air bubbles and rise to the surface for collection |
5.2. Collecting Power Comparison (Xanthate Series)
| Xanthate Type |
Alkyl Chain |
Collecting Power |
Selectivity |
Typical Application |
| Sodium Ethyl Xanthate (SEX) |
Ethyl (C₂) |
Weakest |
Highest |
Selective flotation |
| Potassium Ethyl Xanthate (KEX) |
Ethyl (C₂) |
Weak |
High |
Selective flotation |
| Sodium Isopropyl Xanthate (SIPX) |
Isopropyl (C₃) |
Moderate |
Moderate-High |
Wide range |
| Sodium Isobutyl Xanthate (SIBX) |
Isobutyl (C₄) |
Strong |
Moderate |
Balanced |
| Potassium Amyl Xanthate (PAX) |
Amyl (C₅) |
Strongest (Common) |
Lowest |
Difficult ores |
| Sodium Hexyl Xanthate (SHX) |
Hexyl (C₆) |
Very Strong |
Very Low |
Refractory ores, difficult conditions |
SECTION 6: APPLICATION AREAS
6.1. Mineral Processing (Flotation)
| Application |
Description |
| Copper Ores |
Flotation of chalcopyrite and other copper sulfide minerals; very strong collecting power ensures high recovery even in difficult conditions |
| Lead-Zinc Ores |
Flotation of galena and sphalerite; useful in bulk sulfide flotation circuits |
| Nickel Ores |
Flotation of pentlandite and other nickel sulfide minerals |
| Gold Ores |
Flotation of gold-bearing sulfide minerals |
| Refractory Ores |
Difficult-to-float ores where maximum recovery is prioritized over selectivity |
| Bulk Sulfide Flotation |
Bulk recovery of sulfide minerals in complex ores |
| Pyrite Flotation |
Pyrite recovery (gold-bearing pyrite) |
| Scavenger Flotation |
Recovery of residual valuable minerals from tailings |
6.2. Other Applications
| Application |
Description |
| Rubber Industry |
Used as a vulcanization accelerator in rubber processing |
| Hydrometallurgy |
Pre-concentration of ores before leaching |
| Analytical Chemistry |
Reagent for metal ion detection and precipitation |
SECTION 7: ADVANTAGES AND DISADVANTAGES
7.1. Advantages
| Advantage |
Description |
| Very Strong Collector |
Longest commonly used xanthate chain (C₆); provides maximum collecting power |
| High Recovery |
Ensures maximum recovery of sulfide minerals even in difficult flotation conditions |
| Effective on Refractory Ores |
Highly effective on difficult-to-float ores where shorter-chain xanthates fail |
| Versatile |
Can be used in copper, lead, zinc, nickel, gold, and pyrite flotation |
| Coarse Particle Recovery |
Effective at coarse grind sizes |
| Bulk Flotation |
Excellent for bulk sulfide flotation and scavenger operations |
7.2. Disadvantages
| Disadvantage |
Description |
| Very Low Selectivity |
Least selective xanthate; collects non-target minerals extensively; results in low concentrate grade |
| Environmental Risk |
Decomposition releases carbon disulfide (CS₂), which is toxic and environmentally hazardous |
| Hazardous Material |
Self-heating; flammable; requires special safety measures for storage and handling |
| Poor Stability |
Sensitive to heat, moisture, light, and acidic conditions |
| Strong Odor |
Very strong, unpleasant, pungent odor during handling and use |
| High Dosage Required |
Often requires higher dosages compared to shorter-chain xanthates |
| Limited Use |
Typically limited to applications where maximum recovery is prioritized over selectivity |
SECTION 8: TYPICAL DOSAGE AND APPLICATION
8.1. Recommended Dosage
| Parameter |
Value |
| Typical Dosage Range |
50 – 500 g/t of ore (depending on ore type and conditions) |
| Optimal Dosage |
Determined by flotation test work |
| Addition Point |
Added to the grinding circuit or conditioning tank |
| Solution Strength |
Typically 5-10% aqueous solution |
8.2. Application Instructions
| Step |
Description |
| 1 |
Prepare SHX solution by dissolving in water (typically 5-10% solution) |
| 2 |
Add to the flotation circuit at the designated addition point |
| 3 |
Condition the pulp for 2-5 minutes for optimal adsorption |
| 4 |
Adjust dosage based on ore characteristics and flotation response |
| 5 |
Use solutions within 2-3 days to prevent decomposition |
8.3. Xanthate Selection Guide by Application
| Application |
Recommended Xanthate |
Reason |
| Selective Flotation |
SEX, KEX, SIPX |
Higher selectivity required |
| Copper Sulfides (Clean Ores) |
SEX, SIPX |
Good balance of selectivity and recovery |
| Gold-Bearing Pyrite |
PAX, SIPX |
PAX is strongest for pyrite |
| Nickel Sulfides |
PAX, SIBX |
Good collecting power |
| Lead-Silver Ores |
PAX |
Best recoveries |
| Refractory/Difficult Ores |
SHX, PAX |
Maximum collecting power required |
| Bulk Sulfide Flotation |
SHX, PAX, SIBX |
Strong collecting power needed |
| Scavenger Flotation |
SHX, PAX |
Maximum recovery from tailings |
SECTION 9: QUALITY SPECIFICATIONS
| Parameter |
Specification |
| Appearance |
Pale yellow to light brown powder, flakes, or pellets |
| Purity (Active Content) |
≥ 90.0% |
| Free Alkali (as NaOH) |
≤ 0.5% |
| Moisture |
≤ 4.0% |
| Insoluble Matter |
≤ 0.5% |
| pH (1% solution) |
8 – 11 |
| Sulfide Content |
< 0.5% |
| Heavy Metals (as Pb) |
< 10 ppm |
| HS Code |
2930902000 |
SECTION 10: PACKAGING OPTIONS
| Packaging Type |
Quantity |
Material |
| Plastic Drum |
100 – 200 kg |
HDPE |
| Fiber Drum |
100 – 150 kg |
HDPE + PE liner |
| Multi-layer Bag |
25 kg |
PE-lined kraft paper |
| Big-Bag |
500 – 1000 kg |
Polypropylene (with PE liner) |
SECTION 11: STORAGE AND SHELF LIFE
| Parameter |
Information |
| Storage Conditions |
Cool (<15-25°C), dry, well-ventilated area; away from direct sunlight |
| Container Requirements |
Tightly closed, original packaging |
| Protect From |
Heat, moisture, direct sunlight, acidic conditions, oxidizing agents |
| Shelf Life |
6-12 months (unopened original packaging) |
| Stability Note |
Decomposes in acidic conditions; sensitive to heat and moisture; decomposes to carbon disulfide (CS₂); self-heating in large quantities |
SECTION 12: SAFETY AND HEALTH INFORMATION
12.1. Classification
| Parameter |
Information |
| GHS Classification |
Self-heating substances (Category 2), Acute Toxicity (Category 4), Skin Irritation (Category 2), Eye Irritation (Category 2A), Reproductive Toxicity (Category 2), Specific Target Organ Toxicity (Category 2/3) |
| Signal Word |
WARNING |
| UN Number |
3342 |
| Hazard Class |
4.2 (Substances liable to spontaneous combustion) |
12.2. Hazard Statements
| Code |
Statement |
| H252 |
Self-heating in large quantities; may catch fire |
| H302 |
Harmful if swallowed |
| H315 |
Causes skin irritation |
| H319 |
Causes serious eye irritation |
| H335 |
May cause respiratory irritation |
| H361 |
Suspected of damaging fertility or the unborn child |
| H373 |
May cause damage to organs through prolonged or repeated exposure |
12.3. Precautionary Statements
| Code |
Statement |
| P201 |
Obtain special instructions before use |
| P235+P410 |
Keep cool. Protect from sunlight. |
| P261 |
Avoid breathing dust |
| P280 |
Wear protective gloves, protective clothing, eye/face protection |
| P301+P312 |
IF SWALLOWED: Call a POISON CENTER/doctor if you feel unwell |
| P305+P351+P338 |
IF IN EYES: Rinse cautiously with water for several minutes |
| P308+P313 |
IF exposed or concerned: Get medical advice/attention |
| P403+P233 |
Store in a well-ventilated place. Keep container tightly closed |
12.4. Toxicological Information
| Parameter |
Value |
| Oral LD50 (Rat) |
Acute Oral Toxicity – Category 4 (Harmful if swallowed) |
| Dermal LD50 (Rabbit) |
Acute Dermal Toxicity – Category 4 |
| Skin Irritation |
Category 2 (Causes skin irritation) |
| Eye Irritation |
Category 2A (Causes serious eye irritation) |
| Inhalation |
May cause respiratory irritation |
SECTION 13: ENVIRONMENTAL INFORMATION
| Parameter |
Information |
| Decomposition |
Decomposes to carbon disulfide (CS₂), which is toxic and environmentally hazardous |
| Aquatic Toxicity |
Toxic to aquatic organisms |
| Persistence |
Degrades in the environment; may persist under certain conditions |
| Environmental Precautions |
Prevent entry into drains, soil, and surface waters |
SECTION 14: TRANSPORT INFORMATION
| Parameter |
Information |
| UN Number |
3342 |
| UN Proper Shipping Name |
XANTHATES (Sodium Hexyl Xanthate) |
| Hazard Class |
4.2 (Substances liable to spontaneous combustion) |
| Packing Group |
II or III (depending on formulation) |
| ADR/RID |
Regulated |
| IMDG Code |
Regulated |
| IATA (Air) |
Regulated |
SECTION 15: REGULATORY STATUS
| Parameter |
Information |
| TSCA (USA) |
Yes |
| EINECS |
Not assigned |
| HS Code |
2930902000 |
SECTION 16: SUMMARY AND CRITICAL NOTES
Product Summary
| Parameter |
Value |
| Product |
Sodium Hexyl Xanthate (SHX) |
| CAS Number |
35042-31-6 |
| Chemical Formula |
C₆H₁₃OCS₂Na |
| Appearance |
Pale yellow to light brown powder, flakes, or pellets |
| Primary Function |
Very strong collector for sulfide minerals in froth flotation |
| Key Feature |
Very strong collecting power, but very low selectivity |
Critical Notes
-
Very Strong Collector: SHX has the longest commonly used alkyl chain (C₆), providing the very strong collecting power among the alkyl xanthate series.
-
Very Low Selectivity: Due to its very strong collecting power, SHX has the lowest selectivity among all common xanthates; results in very low concentrate grade but maximum recovery.
-
Primary Applications: Refractory and difficult-to-float ores, bulk sulfide flotation, scavenger flotation operations.
-
Refractory Ores: Preferred for difficult ores requiring maximum collecting power; effective at coarse grind sizes.
-
Mechanism: SHX adsorbs onto sulfide mineral surfaces through chemisorption; binding strength increases with chain length (Hexyl > Amyl > Isobutyl > Ethyl).
-
Decomposition: Decomposes in acidic conditions (pH <7) to carbon disulfide (CS₂); must be stored in alkaline conditions.
-
Safety: Self-heating substance (Category 2); flammable; toxic; requires careful handling and storage.
-
Environmental: Decomposition products (CS₂) are toxic to the environment; prevent entry into drains and waterways.
-
Limited Use: Typically limited to applications where maximum recovery is prioritized over selectivity.
-
Chain Length Rule: As alkyl chain length increases, collecting power increases, but selectivity decreases dramatically. SHX is used when recovery is the absolute priority.
-
Comparison to PAX: SHX (C₆) is even stronger and less selective than PAX (C₅), making it suitable for the most difficult flotation conditions.
-
Solution Stability: SHX solutions should be used within 2-3 days to prevent decomposition into carbon disulfide.
-
Aqueous Degradation: Degrades faster than shorter-chain xanthates; recommended to prepare solutions fresh daily.
-
Compatibility: Can be used with lime to maintain alkaline pH; compatible with frothers and modifiers.
-
Alternative Name: Also known as Sodium Hexyl Xanthogenate and Sodium Hexyl Dithiocarbonate.
IMPORTANT DECLARATION: This Technical Data Sheet (TDS) is for informational purposes only and has been prepared based on available technical data. The user is responsible for determining the product's suitability for their specific application and for complying with all local, national, and international regulations. For complete safety, storage, use, transport, waste, and regulatory compliance information, refer to the official Safety Data Sheet (SDS/MSDS) provided by the manufacturer/supplier.
