Patent ID: 7615652

Claim:
A method for production of a dianhydrosugar alcohol, comprising: providing a solid acid catalyst within a continuous reactor, the solid acid catalyst being selected from the group consisting of heteropolyacid and an ion exchange resin, acidic clay, molecular sieve material, and sulfated zirconia; passing a feed stream through the continuous reactor at a first temperature of from about 70° C. to about 120° C., the feed stream comprising at least one sugar and/or sugar alcohol in an absence of solvent upon entry into the reactor, at least a portion of the at least one sugar and/or sugar alcohol being converted to a monoanhydrosugar isomer during the passing, the residence within the continuous reactor being from about 10 minutes to about 30 minutes; obtaining a product material from the continuous reactor, the product material comprising the monoanhydrosugar isomer at an abundance of at least 50% relative to a total of monoanhydrosugars in the product material; separating the monoanhydrosugar isomer from undesirable monoanhydrosugars present in the product material; and after the separating, subjecting the monoanhydrosugar isomer to a second temperature to convert at least some of the monoanhydrosugar isomer to a dianhydrosugar alcohol, the second temperature being greater than the first temperature.