US Patent 7741498 Propylene oxide process

A process for making propylene oxide from propylene is disclosed. The process comprises reacting propylene, oxygen, and hydrogen in the presence of a catalyst and a solvent to produce a reaction mixture comprising propylene oxide. Separation of propylene, oxygen, hydrogen, and propylene oxide from the reaction mixture results in a residual mixture comprising methanol. A portion of the residual mixture is recycled to the reaction. A portion of the residual mixture is distilled to generate a distilled methanol stream, which is recycled to the reaction.