This invention provides a method for separating ASO from a mixture containing ASO, HF and sulfolane comprising the steps of:(a) contacting said mixture with a sorbent to selectively sorb HF and water from said mixture to evolve an intermediate product containing less than 5 weight percent HF;(b) charging said intermediate product to a gravitational separation zone;(c) holding said intermediate product in said gravitational separation zone for time sufficient to evolve two at least partially immiscible liquid phases in said gravitational separation zone; and(d) withdrawing a less-dense phase enriched in ASO and a more-dense phase enriched in sulfolane from said gravitational separation zone.