Phenol is highly corrosive and toxic. It mainly affects the central nervous system. The oral lethal dose for adults is 1 g. It can be irritating, numbing or necrotizing to the skin. It is toxic to skin contact, swallowing or inhalation of phenol. Misuse of a small amount of phenol can cause nausea, vomiting, shock, coma and even death in case of respiratory failure. Very few amounts are used as a preservative, so that adverse reactions are rarely found.
Due to its high toxicity, it has been replaced by more effective and less toxic phenolic derivatives.
Phenol, C6H5OH, also known as carbolic acid and phenylic acid, is a white poisonous crystalline solid that melts at 43 °C (110 OF) and boils at 182°C (360 OF). Phenol has a sharp burning taste,a distinctive odor, and it irritates tissue. It is toxic not only by ingestion or inhalation, but also by skin absorption. Phenol is soluble in water,alcohol,and ether. It is used in the production of resins,germicides,weedkillers,pharmaceuticals, and as a solvent in the refining of lubricating oils.
Coal tar was once the main source of phenol, and was extracted from sodium hydroxide solution. In earlier time, people use sulfonation method to produce phenol: react sodium benzene sulfonate with sodium hydroxide to generate the sodium salt of phenol, and then treat it with acid to obtain phenol. In recent years, hydrolyzing chlorobenzene or oxidizing cumene has become the major production method. The by-product acetone in latter method is also an important industrial raw material, so oxidizing cumene is more economic industrially thus widely applied.
This method generates cumene from propylene and benzene in the presence of aluminum trichloride. It oxidizes to cumene hydroperoxide and then decomposes with cation exchange resin to give phenol and acetone. For each ton of phenol produced, 0.62 tons of acetone can be produced.
se sulfuric acid to sulfonate benzene to generate benzene sulfonic acid, neutralize it with sodium sulfite, and then undergo acidification and vacuum distillation in caustic soda solution.
Hydrogen benzene hydrolysis method: hydrogen benzene is hydrolyzed in caustic soda solution with high temperature and high pressure to generate phenol sodium, which is then neutralized to give phenol.
ChEBI: An organic hydroxy compound that consists of benzene bearing a single hydroxy substituent. The parent of the class of phenols.
PHENOL is a weak acid. Reacts exothermically with bases. Reacts with strong oxidizing agents. Emits acrid smoke and irritating fumes when heated to decomposition. Undergoes, in the presence of aluminum chloride, potentially explosive reactions with nitromethane, butadiene, formaldehyde, peroxodisulfuric acid, peroxosulfuric acid, and sodium nitrite . Reacts violently with sodium nitrate in the presence of trifluoroacetic acid [Bretherick, 5th ed., 1995, p. 770]. May corrode lead, aluminum and its alloys, certain plastics, and rubber. Phenol may explode in contact with peroxodisulfuric acid (Dns, J. Ber., 1910, 43, 1880; Z. Anorg. Chem., 1911, 73, 1911.) or peroxomonosulfuric acid. (Sidgwick, 1950, 939)
Air & Water Reactions
Decomposes slowly in air. Mixtures of 9-10% phenol in air are explosive. Soluble in water
Flammable vapors when heated. Runoff from fire control water may give off poisonous gases and cause pollution. Mixtures of 9-10% phenol in air are explosive. Avoid aluminum chloride/nitrobenzene mixture, peroxodisulfuric acid, peroxomonosulfuric acid and strong oxidizing agents. Decomposes slowly on air contact. Avoid contact with strong oxidizing agents.
A solid melting at 110°F. Colorless if pure, otherwise pink or red. Flash point 175°F. Density 9.9 lb / gal. Vapors are heavier than air Corrosive to the skin (turning skin white) but because of its anesthetic quality numbs rather than burn. Lethal amounts can be absorbed through the skin. Used to make plastics and adhesives.
Steam is passed through a boiling solution containing 1mole of phenol and 1.5-2.0moles of NaOH in 5L of H2O until all non-acidic material has distilled. The residue is cooled, acidified with 20% (v/v) H2SO4, and the phenol is separated, dried with CaSO4 and fractionally distilled under reduced pressure. It is then fractionally crystallised several times from its melt [Andon et al. J Chem Soc 5246 1960]. Purification via the benzoate has been used by Berliner, Berliner and Nelidow [J Am Chem Soc 76 507 1954]. The benzoate,(m 70o, b 314o/760mm), is crystallised from 95% EtOH, then hydrolysed to the free phenol by refluxing with two equivalents of KOH in aqueous EtOH until the solution becomes homogeneous. It is acidified with HCl and extracted with diethyl ether. The ether layer is freed from benzoic acid by thorough extraction with aqueous NaHCO3, and, after drying and removing the ether, the phenol is distilled. Phenol has also been crystallised from a 75% w/w solution in water by cooling to 11o and seeding with a crystal of the hydrate. The crystals are centrifuged off, rinsed with cold water (0-2o), saturated with phenol, and dried. It can be crystallised from pet ether [Berasconi & Paschalis J Am Chem Soc 108 2969 1986]. Draper and Pollard [Science 109 448 1949] added 12% water, 0.1% aluminium (can also use zinc) and 0.05% NaHCO3 to phenol, and distilled it at atmospheric pressure until the azeotrope was removed, The phenol was then distilled at 25mm. Phenol has also been dried by distillation from the *benzene solution to remove the water/*benzene azeotrope and the excess *benzene, followed by distillation of the phenol at reduced pressure under nitrogen. Processes such as this are probably adequate for analytical grade phenol which has as its main impurity water. Phenol has also been crystallised from pet ether/*benzene or pet ether (b 40-60o). The purified material is stored in a vacuum desiccator over P2O5 or CaSO4. [Beilstein 6 IV 531.]
Phenol is an important organic chemical raw material, widely used in the production of phenolic resin and bisphenol A, in which bisphenol A is important raw material for polycarbonate, epoxy resin, polysulfone resin and other plastics. In some cases the phenol is used to produce iso-octylphenol, isononylphenol, or isododecylphenol through addition reaction with long-chain olefins such as diisobutylene, tripropylene, tetra-polypropylene and the like, which are used in production of nonionic surfactants. In addition, it can also be used as an important raw material for caprolactam, adipic acid, dyes, medicines, pesticides and plastic additives and rubber auxiliaries.
Purified for molecular genetics applications
Phenol is a stable chemical substance and appear as colourless/white crystals with a
characteristic, distinct aromatic/acrid odour. It is reactive and incompatible with strong
oxidising agents, strong bases, strong acids, alkalis, and calcium hypochlorite. Phenol is
flammable and may discolour in light.
Phenol is used in the manufacture or production of explosives, fertiliser, coke, illuminating
gas, lampblack, paints, paint removers, rubber, perfumes, asbestos goods, wood
preservatives, synthetic resins, textiles, drugs, and pharmaceutical preparations. It is also
extensively used as a disinfectant in the petroleum, leather, paper, soap, toy, tanning, dye,
and agricultural industries.
Phenol is commonly known as carbolic acid. The chemical properties of phenol are very active, and it turns to reddish crystals in the air or in contact with any impurities. It absorbs the moisture in the air and gradually liquefies in the air. Phenol is slightly soluble in water, soluble in benzene, alkaline solution and organic solvents such as ethanol, ether, chloroform, glycerol, etc. Phenol is weakly acidic and reacts with base to form salt. It appears blue when being dissolved in ferric chloride solution.
Toxic hazard rating is very toxic: probable oral lethal dose (human) is 50-500 mg/kg. Ingestion of 1 gram has been lethal to humans. Lethal amounts may be absorbed through skin or inhaled. Industrial contact can cause chronic poisoning with kidney and liver damage. Persons affected with hepatic or kidney diseases are at a greater risk.