Reference product: p-chlorophenol [kg]
Location: RoW - Rest-of-World
The process “p-chlorophenol, at plant, GLO" is modelled for the production of p-chlorophenol from phenol. Raw materials are modelled with a stoechiometric calculation. Emissions are estimated. Energy consumptions, infrastructure and transports are calculated with standard values.
p-Chlorophenol (C6H5ClO; CAS 106-48-9, 4-chlorophenol) is solid at ambient temperature and has a strong characteristic odour. It is only slightly soluble in water, but highly soluble in alcohols. The mono-, di-, and trichlorophenols which have no chlorine atom in the meta position relative to OH are 2-chlorophenol, 4-chlorophenol, 2,4-dichlorophenol, 2,6-dichlorophenol, and 2,4,6-trichlorophenol. The tetrachlorophenols and pentachlorophenol are also included with this type. These compounds are obtained by the direct chlorination of phenol: C6H6O + Cl2 → C6H5ClO + HCl (Ullmanns 2000). The chlorination of melted phenol using chlorine gas yields a mixture of ortho and para monochlorophenols with an o/p ratio of ca. 0.54 (35/65), which is scarcely dependent on temperature. The distribution between the two isomers depends especially on the nature of the chlorination reagent and the characteristics of the reaction medium. The formation of 2-chlorophenol is favored by an aprotic nonpolar solvent medium, such as hexane, carbon tetrachloride, or dichloroethane. The o/p ratio is also higher for reactions with a low concentration of phenol and a high temperature. The chlorination of a 5 % solution of phenol in perchloroethylene at 110 °C in the presence of 0.01 wt % diisopropylamine gives a very high o/p ratio, ca. 15. Chlorinations using aqueous sodium hypochlorite] at pH 10, tert-butyl hypochlorite and alkali phenolates dispersed in an anhydrous medium, or chlorine in acetic acid in the presence of acetic anhydride also favor the formation of 2-chlorophenol.
The formation of 4-chlorophenol is favored by chlorination in a polar medium, such as acetonitrile, nitrobenzene, or ether. Substitution in the para position is also strongly favored by the use of sulfuryl chloride as a chlorinating agent (o/p = 0.35). Certain organic sulfides, e.g., diphenyl sulfide, activate chlorination and favor substitution at the para position. Chlorination using copper(II) chloride in aqueous hydrochloric acid in the presence of oxygen leads to 4-chlorophenol (almost 100 %).
Mono-, di-, and trichlorophenols are made industrially by chlorination of phenol with chlorine gas in a melt in cast-iron reactors. The isomer distribution in the product may be adjusted to market demands by the chlorination level and by recycling various intermediates. The yield, based on chlorine and phenol, is greater than 95 %.
Tetrachlorophenols and pentachlorophenol are produced batchwise in nickel reactors by the chlorination of less halogenated chlorophenols in the presence of aluminum trichloride or iron trichloride.
Chlorophenols are used as agricultural chemicals, pharmaceuticals, biocides, and dyes.
The preparation of agricultural chemicals consumes 80 – 90 % of chlorophenol production. The annual consumption of the herbicides 2,4-dichlorophenoxyacetic acid (2,4-D) and 2,4-dichlorophenoxy-4-butyric acid is 30 – 40 kt. Hoelon (Hoechst), Modown (Mobil), Ronstar (Rhône-Poulenc), and TOK E-25 (Rohm and Haas) are among the major herbicides. Curacron (Ciba Geigy) exemplifies the insecticides made from chlorophenols. Among the fungicides are Bayleton (Bayer), MO (Mitsui Toatsu Chemicals), and Procloraz or Sportak (Boots).
Pharmaceuticals derived from chlorophenols include clofibrate, ethyl 2-(4-chlorophenoxy)-2-methylpropionate (ICI), used in the treatment for high serum cholesterol, and Mervan or Aldofene, an antiinflammatory and analgesic drug (Continental Pharma).
Biocides that are based on chlorophenols include the molluscicide Bayluscide (Bayer) and the bactericide Santophen or Chlorophen (Monsanto). Pentachlorophenol is also used to make wood and cellulose preservatives, esters for the textile and leather industries, paints, varnishes, and organic adhesives.
The sodium salt of pentachlorophenol is an active, water-soluble material. It is used as a preservative for such organic materials as freshly sawn wood (against blue rot), paints, adhesives, textiles, leather, and furs.
Chlorophenols are used in the synthesis of anthraquinone dyes.
Frischknecht R., Jungbluth N., Althaus H.-J., Doka G., Dones R., Heck T., Hellweg S., Hischier R., Nemecek T., Rebitzer G. and Spielmann M. (2007) Overview and Methodology. Final report ecoinvent v2.0 No. 1. Swiss Centre for Life Cycle Inventories, Dübendorf, CH, retrieved from: www.ecoinvent.org.
Gendorf (2000) Umwelterklärung 2000, Werk Gendorf. Werk Gendorf, Burgkirchen as pdf-File under: http://www.gendorf.de/pdf/umwelterklaerung2000.pdf
François Muller/Liliane Caillard: Chlorophenols. Published online: 2000. In: Ullmann's Encyclopedia of Industrial Chemistry, Seventh Edition, 2004 Electronic Release (ed. Fiedler E., Grossmann G., Kersebohm D., Weiss G. and Witte C.). 7 th Electronic Release Edition. Wiley InterScience, New York, Online-Version under: DOI: 10.1002/14356007.a07_001
[This dataset has been generated using the system model "Allocation, cut-off by classification". A system model describes how activity datasets are linked to form product systems. The allocation cut-off system model subdivides multi-product activities by allocation, based on a physical properties, economic, mass or other properties. By-products of waste treatment processes are cut-off, as are all by-products classified as recyclable. Markets in this model include all activities in proportion to their current production volume.
Version 3 of the ecoinvent database offers three system models to choose from. For more information, please visit: https://www.ecoinvent.org/database/system-models-in-ecoinvent-3/system-models-in-ecoinvent-3.html)]
chlorination of phenol