METHOD OF PRODUCING AMMONIUM SULPHATE Russian patent published in 2009 - IPC C01C1/242 

FIELD: chemistry.

SUBSTANCE: ammonium sulphate is produced through neutralisation of spent sulphuric acid from sulphuric acid alkylation of isobutane with olefins, containing organic impurities in form of organic sulphoacids and sulphoesters, with ammonia in the presence of an extractant. The extractant used is acetone or a mixture of ethanol and acetone, or a mixture of ethanol or acetone with butyl, propyl, isobutyl or isoamyl alcohol, or a mixture of ethanol or acetone with tetrahydrofuran or 1,4-dioxane with mass ratio of sulphuric acid in terms of monohydrate to extractant equal to 1:0.2-0.4. The organic layer formed is separated from the aqueous layer, and the latter is evaporated and dried.

EFFECT: increased raw material base for producing ammonium sulphate due to use of wastes, obtaining a product which does not contain organic impurities.

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