Analysis of sulfur compounds in light distillates

Since recent regulatory changes have lowered sulfur levels in refined petroleum products, there is an increased interest in speciation of sulfur compounds resistant to and/or formed during processing. This report describes a method to differentiate between blends of sulfides and thiols via derivatization with pentafluorobenzoyl chloride (PFBC). Derivated thiol boiling points increase sufficiently to provide separation from sulfides, which do not react. The method has been applied to a group of light distillates and catcracked products known to contain sulfur compounds, and preliminary results are reported here