Naphthenic Acid
Synonyms
Carboxylic acids, naphthenic;
Naphthenic acids;
Category
Anionic Surfactant
> Carboxylate
>> Cyclic Carboxylate
>>> Alicyclic Carboxylate
>>>> Naphthenate (Petroleum acid Salt)
Chemical Numbering System
CAS: 1338-24-5
EINECS: 215-662-8
Molecular Formula & Molecular Weight
Molecular Formula: N/A
Molecular Weight: N/A
Structure
Properties
Appearance (1), yellow to brown liquid (refined naphthenic acid).
Solubility slightly soluble in water, soluble in petroleum ether, benzene.
Stability stable.
Risk Liquid 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 |
3000mg/kg[1] |
|
rat intraperitoneal LD50 |
640mg/kg[1] |
Ecology may be hazardous to environment. Water body should be given special attention.
Biodegradability biodegradable.
Characteristics excellent emulsifying, dispersing, cleansing, lubricating, solubilizing, anticorrosive abilities. Corrosion to lead, zinc.
Note (1), A complex mixture of acids is isolated from petroleum. In general, the average molecular weight is between 180 and 350. For naphthenic acid of low molecular weight, the main components are the cyclopentyl derivatives. For naphthenic acid of high molecular weight, the main components are the mixtures of monocyclic, bicyclic, and polycyclic acids. The carboxyl group is directly connected to the ring, or connected to the ring through the short alkyl group, and the number of alkyl carbon is generally between 1 and 4. Because of the difference of crude oil, the obtained naphthenic acid must be different, which means that the performance of naphthenic acid is uncertain.
Synthesis
Quality Standards & Test Methods
1, Physical and chemical indexes
|
Item |
Physical and chemical indexes |
|
Liquid |
|
|
Actives, %, ≥ |
55.0 - 85.0 |
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 |
|
Liquid |
|
|
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, Product standards
(1), Chinese standards
(1a), SH/T 0530 Petroleum acid
4, 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 emulsifying agent, dispersing agent.
Use as cleansing agent.
Use as lubricant.
Use as corrosion inhibitor.
Use as solvent.
2, Organic synthesis
Used in preparation of naphthenates, naphthenic acid esters.
Manufacturers
References
[1]: ChemIDplus. 1338-24-5, Naphthenic acid
Update: 20131114(1); 20181023(2);