Hexadecanoic Acid
Synonyms
Palmitic acid;
Category
Anionic Surfactant
> Carboxylate
>> Chain Carboxylate
>>> Alkyl Carboxylate
>>>> Linear Alkyl Carboxylate
Chemical Numbering System
CAS: 57-10-3
EINECS: 200-312-9
Molecular Formula & Molecular Weight
Molecular Formula: C16H32O2
Molecular Weight: 256.42
Structure
Properties
Appearance (1), white solid, pearl.
Solubility insoluble in water. soluble in toluene.
Physical - chemical properties
|
Water solubility, mg/L |
0.04 (25°C)[1] |
|
Melting point, °C |
62.5[1] |
Stability stable.
Risk Solid form: flammable material; irritation, irritation to skin, eye, respiratory system. Harmful products of combustion are CO, CO2 and so on. Contact with strong oxidants, can cause to burn.
GHS label: 
Animal Toxicity
Table 1 Animal toxicity values
|
rat oral LD50 |
> 10000mg/kg[2] |
|
mouse intravenous LD50 |
57mg/kg[2] |
Ecology may be hazardous to environment. Water body should be given special attention.
Biodegradability biodegradable.
Characteristics excellent lubricating, cleansing, emulsifying, dispersing, solubilizing abilities. Nonresistant to hard water. Typical ingredient in soap.
Synthesis
1, Fractionation method
(1), The crude fatty acids are obtained by saponifying hydrolysis reaction of animal fat or palm oil.
(2), Crude fatty acids are washed, distilled and decolored, then obtain finished palmitic acid. At the same time, obtain by-product glycerin.
Quality Standards & Test Methods
1, Physical and chemical indexes
|
Item |
Physical and chemical indexes |
|
Solid |
|
|
Actives, %, ≥ |
95.0 |
Test Methods
(1), Actives
GB/T 13173 Surface active agents -- Detergents -- Testing methods
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, Hazardous substances indexes
|
Item |
Hazardous substances indexes |
|
Solid |
|
|
Heavy metals (as Pb), mg/kg, ≤ |
20 |
|
As, mg/kg, ≤ |
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.
(b), Used in cosmetics, should be test for harmful substances; or furtherly test for microorganisms.
Major Uses
1, Typical applications
Use as lubricant.
Use as cleansing agent.
Use as emulsifying agent, dispersing agent.
2, Household detergents
Use as cleansing agent.
3, Personal care products
Emulsifying agent, emollient in personal care products.
4, Machinery industry
Lubricant in metal processing, machinery.
5, Organic synthesis
Widely used in preparation of palmitic acid ester. Palmitic acid ester can be used in personal care products, food, medicine, etc.
Widely used in preparation of palmitic acid salts. Palmitic acid salts can be used in personal care products, household cleaning products, fabricated metal products, plastic products, etc.
Widely used in preparation of antioxidants.
Used in preparation of lubricants.
Used in preparation of food additives
6, Pets
Use as cleansing agent, emulsifying agent.
7, Powder forming
Lubricant, release agent in powder forming.
8, Light industry
Combustion controlling agent in candles.
9, Textile
Waterproofing agent in textile.
10, Food
Food additive, use as perfume, FMEA No. 2832.
Manufacturers
References
[1]: HSDB. 57-10-3, Palmitic acid
[2]: ChemIDplus. 57-10-3, Palmitic acid
Update: 20131102(1); 20171225(2);