Sodium 2-ethylhexyl sulfate
Time: 2012-09-25 16:53:54
Sodium 2-ethylhexyl sulfate
Synonyms
2-Ethylhexyl sulfate sodium salt;
2-Ethyl-1-Hexanol Sodium Sulfate;
2-Ethyl-1-Hexanol Sulfate Sodium Salt;
Sodium(2-Ethylhexyl)Alcohol Sulfate;
Sulfuric Acid, Mono(2-Ethylhexyl) Ester, Sodium Salt;
Sodium ethylhexyl sulfate;
Category
Anionic Surfactant
>> Sulfate
>> Chain Alcohol Sulfate
>> Alkanol Sulfate
>> Branched Alkanol Sulfate
Chemical Numbering System
CASRN126-92-1
EINECS204-812-8
Molecular Formula & Molecular Weight
Molecular Formula: C8H17NaO4S; C8H18O4S.Na (SciFinder Hill Rules)
Molecular Weight: 232.27
Structure
Properties
Appearance    (1), solid; (2), amber liquid.
Odor    faint characteristic odor.
Solubility    soluble in water.
Physical - chemical properties
Flash point, °C
> 93
Stability    stable in alkali, weak acid and hard water; unstable in strong acid, hydrolyzed, reduced to alcohol.
Risk    Solid form: flammable material; irritation, irritation to skin, eye, respiratory. Harmful products of combustion are CO, CO2 and so on. Contact with strong oxidants, can cause to burn.
GHS (Rev.6) label:  
Liquid form: irritation, irritation to skin, eye.
GHS (Rev.6) label:
Animal Toxicity
Table 1 Animal toxicity values
rat oral LD50
4000mg/kg[1]
rat intraperitoneal LD50
320mg/kg[1]
rat subcutaneous LD50
4730mg/kg[1]
rat inhalation LC
> 30mg/m3/8H[1]
rabbit oral LD50
3580mg/kg[1]
rabbit skin LD50
6.54mL/kg[1]
mouse oral LD50
1550mg/kg[1]
guinea pig oral LD50
650mg/kg[1]
guinea pig skin LDLo
1520mg/kg[1]
Ecology    may be hazardous to environment. Water body should be given special attention.
Biodegradability    biodegradable.
Characteristics    excellent wetting, permeating, cleansing, emulsifying, hydrotropic, dispersing, solubilizing abilities. Resistant to hard water. Low foaming. Tolerance to high concentration electrolytes. Tolerance to alkali. Stable to bleach.
Note    (1), Avoid using in children cleaning products, such as shower gels, shampoo, skin care products.
Synthesis
Currently, sulfated reaction through continuous reactor (such as: falling film reactor) is the most widely used method for preparing sulfates.
Generally, 2-ethylhexyl alcohol and sulfur trioxide react through reactor, then sodium hydroxide neutralizes, finally obtain product.
US patent 8,921,588 (Process for preparing sulfates and/or sulfonates in a micro-reaction system) presents a synthetic process. Conditions: mole ratio of sulfur trioxide and alcohols or other raw materials: 1:1; temperature: 30-60°C; reactor: falling film reactor.
US patent 6,060,443 (Mid-chain branched alkyl sulfate surfactants) also presents some synthesis processes of branched chain sulfate.
US patent 6,455,488 (Process of making alkyl sulfate granulates) describes the preparation of a particulate alkyl sulfate, but does not involve the synthesis process.
US patent US 6,331,645 (Process for preparing powdery alkyl sulfates) describes the preparation of a powdery alkyl sulfate, but does not involve the synthesis process.
Quality Standards & Test Methods
1. Physical and chemical indexes
Item
Physical and chemical indexes
Liquid
Actives, %, ≥
39.0 - 40.0
Soluble materials in petroleum ether, %, ≤
0.6
Sodium chloride, %, ≤
0.8
Sodium sulfate, %, ≤
1.0
pH (25°C, 10% solution)
7.5-10.5
Color, APHA (10% solution), ≤
135
Test Methods
(1), Actives
GB/T 5173 Surface active agents and detergents-Determination of anionic-active matter by direct two-phase titration procedure
ISO 2271 Surface active agents -- Detergents -- Determination of anionic-active matter by manual or mechanical direct two-phase titration procedure
(2), Soluble materials in petroleum ether
GB/T 11989 Anionic surface active agents - Determination of soluble matter content in light petroleum
ISO 894 Surface active agents -- Technical sodium primary alkylsulphates -- Methods of analysis
(3), Sodium chloride
GB/T 15963 Sodium lauryl sulfate
ISO 894 Surface active agents -- Technical sodium primary alkylsulphates -- Methods of analysis
(4), Sodium sulfate
GB/T 15963 Sodium lauryl sulfate
ISO 894 Surface active agents -- Technical sodium primary alkylsulphates -- Methods of analysis
(5), pH
GB/T 6368 Surface active agents - Determination of pH of aqueous solution - Potentiometric method
ISO 4316 Surface active agents -- Determination of pH of aqueous solutions -- Potentiometric method
(6), Color
GB/T 605 Chemical reagent - General method for the measurement of colour
ISO 6353-1 Reagents for chemical analysis -- Part 1: General test methods
2. Hazardous substances indexes
Item
Hazardous substances indexes
Solid
Liquid
Heavy metals (as Pb), mg/Kg, ≤
20
20
As, mg/Kg, ≤
3
3
Test Methods
(1), Heavy metals (as Pb)
Safety and Technical Standards for Cosmetics (2015 Edition)
GB/T 30799 The test method of food detergents - Determination of heavy metals
(2), As
Safety and Technical Standards for Cosmetics (2015 Edition)
GB/T 30797 The test method of food detergents - Determination of total arsenic
3. Further explanation
(a), On physical and chemical indexes: firstly, shall be indicated carbon atom distribution; secondly, shall be indicated average molecular weight.
Major Uses
1. Typical applications
Use as wetting agent, permeating agent under alkaline conditions widely.
Use as hydrotrope.
2. Household detergents
Use as cleansing agent.
Particularly suitable for formula containing bleach.
(2a), Bathroom detergent (US 4,124,520)
Formula:
Hexylene glycol    1.0
Dodecylbenzene sulfonic acid    0.3
Sodium hydroxide    0.0126
o-Benzyl-4-chlorophenol    0.15
Tetrasodium EDTA (38%)    12.5
Perfume    0.08
Sodium 2-ethylhexyl sulfate (40%)    4.5
Isopropyl alcohol    2.5
Water    to 100%
(2b), Hard surface detergent (US 6,036,789)
Formula:
Sodium hydroxide    0.6
Sodium hypochlorite    2.5
Fragrance    0.1
Sodium carbonate    5.25
Sodium 2-ethylhexyl sulfate (40%)    1.0
Deionized water    q.s. to 100%
  Features: especially suitable for cleaning ceramic tile surface, can remove soap scum residue.
Patent similar to this: United States Patent 6,022,840 Aqueous cleaning compositions containing 2-ethylhexyl sulfate and C.sub.8 -C.sub.10 alkyldimethylamine oxide for removing soap scum.
3. Personal care products
Use as emulsifying agent, hydrotrope.
4. Industrial cleaning agents
Use as cleansing agent.
5. Emulsion polymerization
Emulsifier, particle size controlling agent in emulsion polymerization.
6. Electroplating industry
Solubilizing agent, nickel-brightener in electroplating industry.
7. Surfactant system
Viscosity reducer in mixed surfactant system.
Manufacturers
 
References
[1]: ChemIDplus. Sodium Ethasulfate, 126-92-1
Update: 20131018(1); 20160810(2);