ТРИ-o-КРЕЗИЛФОСФАТ химические свойства, назначение, производство
Химические свойства
Tricresyl phosphates are available as the
o-isomer (TOCP), the m-isomer (TMCP), and p-isomer
(TPCP). The ortho-isomer is the most toxic of the three;
the meta-and para-isomers are relatively inactive. The
commercial product may contain the ortho-isomer as a
contaminant unless special precautions are taken during
manufacture. Pure tri-para-cresyl phosphate is a solid, and
ortho-and meta-are liquids (see below). The tri-o-cresyl
phosphate will be discussed here as the specific example of
these compounds because it is the most toxic of the tricresyl
phosphates and specifically regulated by OSHA. TOCP
is a colorless to pale yellow, odorless liquid or solid (below
52/F/11℃).
Физические свойства
Tri-o-cresyl phosphate is a colorless to pale yellow, odorless to faint aromatic-like liquid, and it is a solid below the 25.6 °C melting point. It is sparingly soluble in water, but is slightly soluble in ethanol and very soluble in ethyl ether (Budavari, 1996). The vapor pressure of TOCP is 0.00002mm Hg at room temperature, but is 10mm Hg at 265 °C (Bisesi, 1994). It decomposes slightly upon boiling (bp 410 °C) (Budavari, 1996).
Использование
Tri-o-cresyl phosphate is used widely as a gasoline additive,
plasticizer, fire retardant, solvent, extreme pressure
additive, intermediate in pharmaceutical manufacturing,
water-proofing agent, heat exchange medium, and as a
lead scavenger in gasoline.
Методы производства
Prepared from cresol and phosphorus oxychloride, phosphoric acid, or phosphorus
pentachloride. The grades of cresol commonly used are the isomeric (o-, m-, /p-),
and meta-para mixtures from coal tar and cresylic acid from petroleum. Purification
of the product is based on the intended use; the commercial product is
generally obtained as a mixture. A 'refined grade' of tricresyl phosphate is
prepared by vacuum distillation, or alternatively by washing with 2% NaOH and
water (Lowenheim and Moran 1975).
Опасность
Toxic by ingestion and skin absorption. The
oisomer is highly toxic. TLV: 0.1 mg/m3 (skin);
not classifiable as a Human Carcinogen.
Угроза здоровью
TOCP is a highly poisonous compound. Its toxicity is greater than that of the meta- or para-isomer. The toxic routes are inhalation, ingestion, and absorption through the skin; and the symptoms varied with the species and the route of admission.
Ingestion of 40–60 mL of the liquid can be fatal to humans. An oral dose of 6–7 mg/kg has produced serious paralysis in humans (Patty 1949). The toxic symptoms from oral intake can be gastrointestinal pain, diarrhea, weakness, muscle pain, kidney damage, and paralysis. The target organs are the gastrointestinal tract, kidney, central nervous system, and neuromuscular system.
LD50 value, oral (rabbits): 100 mg/kg
Somkuti et al. (1987) reported testicular toxicity of TOCP in adult leghorn roosters. Birds dosed with 100 mg/kg/day exhibited limb paralysis in 7–10 days. Such symptoms are characteristics of delayed neurotoxicity caused by organophosphorus compounds. Analysis at the termination of 18 days indicated a significant inhibition of neurotoxic esterase activity in both brain and testes, and a decrease in sperm motility and brain acetylcholinesterase activity.
TOCP caused adverse reproductive effects in mice, such as increased maternal mortality and a decreased number of viable litters. An LD50 value of 515 mg/kg/day is reported
(Environmental Health Research and Testing 1987)..
Пожароопасность
Noncumbustible solid; vapor pressure 0.02 torr at 150°C (302°F); fire retardant.
Промышленное использование
1. As additive to extreme pressure lubricants.
2. As a non-flammable fluid in hydraulic systems.
3. As plasticizer in lacquers and varnishes.
4. As plasticizer in vinyl plastics manufacture.
5. As flame retardant.
6. As lead scavenger in gasoline.
7. As solvent for nitrocellulose, in cellulosic molding compositions.
Профиль безопасности
Poison by
subcutaneous, intramuscular, intravenous,
and intraperitoneal routes. Moderately toxic
by ingestion. Most of the cases of tri-o-cresyl
phosphate poisoning have followed
its ingestion. In 1930, some 15,000 persons
were affected in the United States, and of
these, 10 died. The responsible material was
found to be an alcoholic drink known as
Jamaica ginger, or "jake." This beverage had
been adulterated with about 2% of tri-o-cresyl
phosphate. The affected persons
developed a polyneuritis, which progressed,
in many cases, with degeneration of the
peripheral motor nerves, the anterior horn
cells, and the pyramidal tracts. Sensory
changes were absent. Since 1930 there have
been several other outbreaks of poisoning
following ingestion of the material. Tri-ocresyl
phosphate is more toxic than the mform,
and much more so than tri-p-cresyl
phosphate or triphenyl phosphate.
Experimental reproductive effects.
flame. Can react with oxidizing materials. To
fight fire, use CO2, dry chemical. When
heated to decomposition it emits highly
toxic fumes of POx. See also
PHOSPHATES.
Combustible when exposed to heat or
Возможный контакт
Tricresyl phosphate is used as an additive
in hydraulic fluids; as a plasticizer; pigment dispersant;
flame retardant; as a plasticizer for chlorinated
rubber; vinyl plastics; polystyrene, polyacrylic, and polymethacrylic
esters; as an adjuvant in milling of pigment
pastes; as a solvent and as a binder in nitrocellulose and
various natural resins, and as an additive to synthetic lubricants
and gasoline. It is also used in the recovery of phenol
in coke-oven wastewaters.
Экологическая судьба
Biological. A commercial mixture containing tricresyl phosphates was completely degraded by
indigenous microbes in Mississippi River water to carbon dioxide. After 4 wk, 82.1% of the
theoretical carbon dioxide had evolved (Saeger et al., 1979).
Chemical/Physical. Tri-o-cresyl phosphate hydrolyzed rapidly in Lake Ontario water,
presumably to di-o-cresyl phosphate (Howard and Doe, 1979). When an aqueous solution
containing a mixture of isomers (0.1 mg/L) and chlorine (3 to 1,000 mg/L) was stirred in the dark
at 20 °C for 24 h, the benzene ring was substituted with one to three chlorine atoms (Ishikawa and
Baba, 1988).
Decomposes at temperatures greater than 424 °C (Dobry and Keller, 1957).
Перевозки
UN2574 Tricresyl phosphate with >3% ortho
(o-) isomer, Hazard Class: 6.1; Labels: 6.1-Poisonous
materials.
Несовместимости
Incompatible with oxidizers (chlorates,
nitrates, peroxides, permanganates, perchlorates, chlorine,
bromine, fluorine, etc.); contact may cause fires or explosions.
Keep away from alkaline materials, strong bases,
strong acids, oxoacids, epoxides. Contact with magnesium
may cause explosion. Organophosphates, such as tricresyl
phosphate, are susceptible to formation of highly toxic and
flammable phosphine gas in the presence of strong reducing
agents such as hydrideds and active metals. Partial oxidation
by oxidizing agents may result in the release of
toxic phosphorus oxides.
Утилизация отходов
TOCP is dissolved in a combustible solvent and burned in a chemical incinerator equipped with an afterburner and scrubber.
ТРИ-o-КРЕЗИЛФОСФАТ препаратная продукция и сырье
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