Thiols can be selectively removed and recovered from a hydrocarbon stream by a heterogeneous reaction with oxides and hydroxides of Pb, Hg(II), and Ba. Alkanethiols of lengths n-C6, n-C8, and n-C12 were found to react with powdered metal oxides to form stable thiolates that are solid at room temperature and insoluble in aqueous and organic solvents. The reaction converts the solid oxide phase into a solid thiolate phase, removing ions from the surface of the oxide, allowing the reaction to reach completion. The thiolates can be removed from the feed stream by filtration. Once separated, the metal and the original thiols can be recovered by extraction with a dilute acid, yielding a metal salt in the aqueous phase and a hydrophobic layer of thiol. The choice of reactive metal oxides may be predicted from simple thermodynamic considerations.
All Science Journal Classification (ASJC) codes
- Chemical Engineering(all)
- Industrial and Manufacturing Engineering