Patent ID: 7709693
Filing Date: 2010-05-04
Classification: C07C

Abstract:
1. In a method for optimizing the production of nitration grade toluene product from a feed containing primarily C6 and C7 aromatic and non-aromatic hydrocarbons including benzene and toluene, said method using a solvent extraction process that forms an extract stream containing primarily benzene and toluene and a separate raffinate stream containing primarily C6 and C7 non-aromatic hydrocarbons and toluene, said extract stream being subjected to a benzene distillation step to remove benzene from said extract stream, said benzene distillation step being followed by a benzene splitter step to remove additional C6 hydrocarbons from said extract stream, said benzene splitter step being followed by a toluene distillation step from which a toluene product is recovered, the improvement comprising adding a portion of said raffinate stream to said extract stream downstream of said benzene distillation step, whereby an optimized volume of nitration grade toluene product is formed.