PRODUCTION AND APPLICATIONS
The most common processes for the production of fluorinated chemicals are electrochemical fluorination (ECF) and telomerisation (a process in which iodic pentafluoroethane reacts with tetrafluoroethylene and ethylene to produce a polyfluoralkane). 3M used to produce PFOS by electrochemical fluorination and was the world's largest producer of PFOS in the period from 1949 to 2002. Production sites were situated in the USA (Decatur, Alabama) and Belgium (Zwijndrecht near Antwerp). Also Miteni (Northern Italy) produced PFAS (Per Fluor Alkylated Substances) by means of ECF. Other manufacturers, including DuPont, Daikin, Clariant, Asahi Glass, Atofina, used the telomerisation process for the production of PFAS. In 2000 EPA discussed PFAS production in the United States, Italy, Germany, Japan and the Soviet Union. Annual production of PFOS derivatives (POSF) in 2000 was estimated at 4650 tons.PFAS is currently still being produced in Germany, Italy and at fifteen locations in China.
The main applications of PFOS are or were:
- additive in fire-fighting foam (AFFF). This has been prohibited since June 27 2011. AFFF extinguishing foams have been actively replaced by PFOS-free extinguishing foams
- mist suppressant and humectant in plating processes
- providing grease, oil and water resistance to various industrial and consumer applications, such as carpets, paper and cardboard (also for food packaging applications), textiles and leather, carpet cleaner, insecticides, 'sticky notes' and non-stick pans (PTFE). Examples of well-known brands are Scotchgard ™, Zonyl, Baygard, Tefal, Post-it, et cetera. These are applications of PFOS-monomers as well as polymers
- surfactants for mining and oil extraction
- currently approved applications in which limited quantities of PFAS are used: photo lithography (etching patterns on computer chips), photographic coatings and hydraulic fluids for aviation
It must be noted that all fluorochemical product, including the polymers, always contain a small quantity of residues, starting material or intermediate product which has not or has partly reacted.Common residues include PFOS and PFOA, or substances that will be eventually converted into PFOS or PFOA.
|Application||Explanation||Estimated amount Use / emissions (tonnes per year)|
|Carpet Industry (i) (Polymers)||Surface treatment dirt and water repellent||15/10|
|Paper and cardboard (Phosphates)||Import and no production of greaseproof paper and similar products||60-105 (ii) / not known|
|Textile Industry (Polymers)||Surface treatment, dirt andwater repellent: e.g. tablecloths, upholstery, rainwear, bedding||not known / 100% (2-3% of the textile)|
|Leather (Polymers)||Surface treatment, water repellent||10-20 /|
|Fire fighting foam (Monomers)||1.13 to 3.81 / 1.13 to 3.81|
|Specialty surfactants (Monomers)||e.g.mist suppressant in chromium plating, chips and aviation fluids||not known|
|Polymerization help (Monomers)||> 1 / > 0.77|
(i) The textile industry in the Netherlands consists of many small and medium sized enterprises, some of which make use of fluorosurfactants. Note: In the UK carpet and textile industries are responsible for about 50% of the national use of PFCs.
(ii) Greaseproof paper is mainly imported from Germany and Scandinavia, and it is estimated that 60-105 tons of fluoroalkyl phosphate are imported with it.Note: Not available, emissions will occur during recyclingand incineration / landfilling.
(iii) In the Netherlands there is one production plant for fluoropolymers that uses more than one tonne of PFOA per year.
- during production
- during use
- released by waste after use (both collected and not collected waste, monomers and polymers)
- waste treatment (incineration, waste water treatment)
- Indirect emissions: chemical impurity during production POSF, or by degradation of POSF derivatives into PFOS in the environment
POSSIBLE SOURCES OF SOIL AND (GROUND)WATER CONTAMINATION
- production, discharges and emissions
- storing extinguishing foams
- use of extinguishing foams (practice locations and fires)
- metalworking industry (chrome plating)
- carpet and textile industry (surface treatment)
- water treatment plants