Benzene production by solvent extraction and hydrodealkylation

摘要

A process for converting a naphtha feedstock to a pure benzene including the steps of: reforming the naphtha; removing a major fraction of C4 - C5 and heavy reformate components to obtain a reformate containing a major portion of C6 - C8 aromatic hydrocarbons and an associated saturated portion; extracting the aromatic hydrocarbons from the reformate countercurrently in a simplified process with a selective hydrophilic solvent, such as sulfolane, having high solubility for aromatic hydrocarbons and low solubility for paraffinic hydrocarbons to obtain an extract stream rich in C6 - C8 aromatic hydrocarbons and a raffinate stream rich in paraffinic hydrocarbons; and recovering the selective solvent from the extract stream to obtain an aromatic component comprising a major C6 - C8 aromatic hydrocarbons and about 3 to 18 wt. % paraffinic hydrocarbon impurity. The paraffinic impurity is removed and alkyl benzenes are converted by hydrodealkylating the aromatic component to recover substantially pure benzene.