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  2. Oleum - Wikipedia

    en.wikipedia.org/wiki/Oleum

    Oleum is generally assessed according to the free SO 3 content by mass. It can also be expressed as a percentage of sulfuric acid strength; for oleum concentrations, that would be over 100%. For example, 10% oleum can also be expressed as H 2 SO 4 ·0.13611SO 3, 1.13611SO 3 ·H 2 O or 102.25% sulfuric acid. The conversion between % acid and ...

  3. Benzene - Wikipedia

    en.wikipedia.org/wiki/Benzene

    Benzene is sufficiently nucleophilic that it undergoes substitution by acylium ions and alkyl carbocations to give substituted derivatives. Electrophilic aromatic substitution of benzene. The most widely practiced example of this reaction is the ethylation of benzene. Approximately 24,700,000 tons were produced in 1999. [73]

  4. Dow process (phenol) - Wikipedia

    en.wikipedia.org/wiki/Dow_process_(phenol)

    Benzene can be easily converted to chlorobenzene by nucleophilic aromatic substitution via a benzyne intermediate. [1] It is treated with aqueous sodium hydroxide at 350 °C and 300 bar or molten sodium hydroxide at 350 °C to convert it to sodium phenoxide, which yields phenol upon acidification. [2]

  5. Aromatic sulfonation - Wikipedia

    en.wikipedia.org/wiki/Aromatic_sulfonation

    The Piria reaction. In the Tyrer sulfonation process (1917), [7] at some time of technological importance, benzene vapor is led through a vessel containing 90% sulfuric acid the temperature of which is increased from 100 to 180°C. Water and benzene are continuously removed and the benzene fed back to the vessel. In this way an 80% yield is ...

  6. Electrophilic substitution - Wikipedia

    en.wikipedia.org/wiki/Electrophilic_substitution

    Electrophilic substitution reactions are chemical reactions in which an electrophile displaces a functional group in a compound, which is typically, but not always, aromatic. Aromatic substitution reactions are characteristic of aromatic compounds and are common ways of introducing functional groups into benzene rings.

  7. Alkylbenzene sulfonate - Wikipedia

    en.wikipedia.org/wiki/Alkylbenzene_sulfonate

    In the most common route benzene is alkylated by long chain monoalkenes (e.g. dodecene) using hydrogen fluoride as a catalyst. [9] The purified dodecylbenzenes (and related derivatives) are then sulfonated with sulfur trioxide to give the sulfonic acid. [10] The sulfonic acid is subsequently neutralized with sodium hydroxide. [1]

  8. Contact process - Wikipedia

    en.wikipedia.org/wiki/Contact_process

    The oleum is then added to water to form sulfuric acid which is very concentrated. Since this process is an exothermic reaction, the reaction temperature should be as low as possible. Purification of the air and sulfur dioxide (SO 2 ) is necessary to avoid catalyst poisoning (i.e. removing catalytic activities).

  9. Benzenesulfonyl chloride - Wikipedia

    en.wikipedia.org/wiki/Benzenesulfonyl_chloride

    The compound is prepared by the chlorsulfonation of benzene: C 6 H 6 + 2HO 3 SCl → C 6 H 5 SO 2 Cl + HCl + SO 3 Benzenesulfonic acid is an intermediate. Diphenylsulfone is a side product. Benzenesulfonyl chloride can also be prepared by treating benzenesulfonate salts with phosphorus oxychloride. [2]