335-67-1 Usage
Description
Pentadecafluorooctanoic acid, also known as Perfluorooctanoic acid (PFOA), is a perfluoroalkyl acid that is synthetically produced as its salts. It is an eight-carbon compound in the perfluoroalkyl family of chemicals, characterized by a nonbranched chain of eight carbon atoms, each fully fluorinated. PFOA is found to be environmentally persistent and bioaccumulative with a long half-life. It is a white to off-white powder or colorless flakes, very soluble in water, and has a pH of 2.6. PFOA can react with bases, oxidizing agents, and reducing agents, and upon decomposition, it can form carbon oxides and hydrogen fluoride.
Uses
1. Used in Chemical Synthesis:
Pentadecafluorooctanoic acid is used as a fluorinated surfactant, primarily as its ammonium salt (APFO), as an aid in the chemical synthesis of fluoropolymers and fluoroelastomers. This application is the primary use of PFOA, and it can be found in various products such as nonstick cookware and utensils, stain-repellant fabric treatments, and waterproof treatments for garments.
2. Used in Electronics, Textiles, and Nonstick Cookware:
PFOA is utilized in the production of fluoropolymers that are used in electronics, textiles, and nonstick cookware. The ammonium salt of PFOA serves as an emulsifier or 'processing aid' in these industrial applications.
3. Used in Aqueous Film-Forming Foams for Firefighting:
PFOA is also used as a fluorosurfactant in aqueous film-forming foams, which are employed for fire fighting purposes.
4. Used as an Ion-Pairing Reagent in Chromatographic Methods:
Pentadecafluorooctanoic acid solution may be used as an ion-pairing reagent in the development of a chromatographic method for the separation and determination of underivatized proteinic amino acids using liquid chromatography with evaporative light scattering detection (LC-ELSD) and atmospheric pressure ionization-mass spectrometry (LC-API-MS).
Environmental and Regulatory Concerns:
Due to concerns about the potential environmental and toxicological impacts of long-chain perfluoroalkyl sulfonates and carboxylic acids, several actions have been taken to reduce the use and emissions of PFOA. These include the phaseout of production by major global manufacturers, stewardship agreements to reduce emissions and product content, restrictions on the use of PFOA in products, and the inclusion of related compounds in the Stockholm Convention on Persistent Organic Pollutants as restricted substances. Efforts are underway by the U.S. EPA and other regulatory bodies to reduce the use of PFOA and replace it with other substances.
Safety Profile
Poison by intraperitoneal route. Mutation data reported. Whenheated to decomposition it emits toxic vapors of Fí.
Environmental Fate
Perfluorooctanoic acid found in the environment may result from waste stream releases from manufacture of cosmetics, lubricants, paints, polishes, adhesives, fabric treatments, and fire-fighting compounds. It can partition to the vapor phase in the atmosphere, where it is degraded atmospherically with a half-life of 31 days. It is very resistant to hydrolysis, and immobile in soil. It will not likely evaporate from soil (depending on soil pH) or surface waters. It is not expected to be absorbed to sediments and suspended particles. Perfluorooctanoic acid is not expected to bioaccumulate in aquatic organisms (BCF =3.1–9.4) (NLM, 2013).
Purification Methods
Crystallise the acid from CCl4 and toluene, and distil it. It forms micelles in H2O and the solubility is 1% in H2O. The acid chloride has b 129-130o/744mm. The amide has m 138o. [Bernett & Zisman J Phys Chem 63 1911 1959, Bro & Sperati J Polym Sci 38 289 1959, Beilstein 2 IV 994.]
Toxicity evaluation
Studies with animals fed PFOA for a long period showed effects
on the stomach, liver, and thyroid hormones. Animal studies
also indicate that PFOA may cause cancer at relatively high
levels. PFOA has also been shown to be a developmental
toxicant, and to have effects on the immune system.
PFOA affects primarily the liver and can cause developmental
and reproductive toxic effects at relatively low dose
levels in experimental animals. It increases the tumor incidence
in rats, mainly in the liver. The carcinogenic effects in rats
appear to be due to indirect/nongenotoxic modes of action.
Epidemiological studies in PFOA-exposed workers do not
indicate an increased cancer risk. There is relatively consistent
evidence of modest positive associations between serum levels
of PFOA and cholesterol, uric acid, and liver enzyme levels.
The critical effects observed in rodents and monkeys are on
the liver and include hypertrophy, changes in liver enzyme
activity, and proliferation of peroxisomes.
In rodents the anionic form of PFOA induces hepatocellular
adenomas, Leydig cell adenomas, and pancreatic hyperplasia.
The genotoxic activity of PFOA is a matter of current debate and
controversy, with classifications as ‘devoid of significant genotoxicity’
as well as ‘weakly nonspecific genotoxic.’ PFOA does
not appear directly genotoxic; animal data indicate that it can
cause several types of tumors and neonatal death and may have
toxic effects on the immune, liver, and endocrine systems.
Check Digit Verification of cas no
The CAS Registry Mumber 335-67-1 includes 6 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 3 digits, 3,3 and 5 respectively; the second part has 2 digits, 6 and 7 respectively.
Calculate Digit Verification of CAS Registry Number 335-67:
(5*3)+(4*3)+(3*5)+(2*6)+(1*7)=61
61 % 10 = 1
So 335-67-1 is a valid CAS Registry Number.
335-67-1Relevant articles and documents
A rationally designed perfluorinated host for the extraction of PFOA from water utilising non-covalent interactions
Omorodion, Harrison,Palenzuela, Miguel,Ruether, Manuel,Twamley, Brendan,Platts, James A.,Baker, Robert J.
, p. 7956 - 7968 (2018)
Perfluorooctanoic acid (PFOA) is a persistent organic pollutant and widespread in the environment. Three hosts have been synthesized based upon the formation of a fluorous cavity and hydrogen bonding receptors with the aim of extracting PFOA from water into organic solvents. The hosts based upon a calix[4]arene functionalized at the lower rim with amide groups and fluorous ponytails are effective for the quantitative removal of PFOA. Modification to a partial cone or a trisaminoamine framework reduces the conformational rigidity and lowers the extraction efficiency. A comprehensive NMR spectroscopic analysis both in solution and the solid state, along with other characterization techniques, has elucidated the stoichiometry of the host:guest species and the binding constants have been measured. A computational study has given further insight into the binding modes and corroborated the spectroscopic measurements.
Preparation method of fluorine-containing carboxylic acid
-
Paragraph 0056-0058, (2020/07/12)
The invention discloses a preparation method of fluorine-containing carboxylic acid. The method comprises the following steps: reacting fluorine-containing carboxylate used as a raw material with an acylating chlorination reagent to obtain a corresponding mixture of fluorine-containing acyl chloride and fluorine-containing anhydride, and hydrolyzing and drying the mixture of fluorine-containing acyl chloride and fluorine-containing anhydride to obtain high-purity fluorine-containing carboxylic acid. The method provided by the invention is suitable for post-treatment of fluorine-containing carboxylic acid prepared by a fluorine-containing olefin (monoolefine, diene, cycloolefin and the like) oxidation method, replaces the traditional strong acid acidification and ether continuous extractionprocess, and is simpler, more convenient and more applicable; and the method can also be used for recovering and purifying a fluorine-containing carboxylate emulsifier. The purity of the fluorine-containing carboxylic acid prepared by the method can reach 98% or above.
Hydrolysis of p-nitrophenyl perfluoroctanoate in mixed surfactant systems
Torres, Maria Florencia,De Rossi, Rita H.,Fernandez, Mariana A.
, p. 28606 - 28614 (2014/07/22)
The kinetics of the hydrolysis reaction of p-nitrophenyl perfluoroctanoate were studied in the presence of different amphiphilic systems: two hydrocarbon surfactants (sodium dodecyl sulfate, SDS, and polyoxyethylene(23)lauryl ether, Brij-35), a perfluorinated detergent (perfluorononanoic acid, PFNA) and in mixtures of SDS-PFNA and Brij-35-PFNA. The study was performed at different compositions of the mixtures (characterized by the molar fraction of PFNA, αPFNA), and for each αPFNA the concentration was varied over a wide range. The kinetic probe p-nitrophenyl perfluoroctanoate showed a very strong interaction with the surfactants. In the presence of the mixed surfactants, the behaviour of the probe changed dramatically with the composition of the mixtures, which indicates that this substrate is very sensitive to the effect of the micellar media, being a very good molecule to study these types of surfactant systems. The use of the studied ester allowed us to confirm the presence of two different aggregates in the mixture Brij-35-PFNA as was previously observed with other techniques. The presence of hydrocarbon-rich micelles at low αPFNA, as well as perfluorinated rich micelles at high αPFNA was also confirmed. The kinetic behaviour of p-nitrophenyl perfluoroctanoate in SDS-PFNA mixtures fully agreed with our previous description of the aggregates formed in this system. The presence of a practically pure PFNA micelle at high αPFNA could be also demonstrated from the kinetic results.
