Bhaskar Arumugam - Kingsport TN,
Nick Collins - Fall Branch TN,
Transito Macias - Petal MS,
Steven Perri - Kingsport TN,
Jeffery Powell - Blountville TN,
Chester Sink - Kingsport TN,
Michael Cushman - Punta Gorda FL,
The present invention provides methods and an apparatus for the manufacture of an L-ascorbic acid product in high yield by direct conversion of an aqueous solution containing 2-keto-L-gulonic acid by contact with an acid catalyst or under thermal self-catalyzed conditions at a conversion level that maximizes the formation of L-ascorbic acid and minimizes decomposition of the L-ascorbic acid thus formed. The separation process for L-ascorbic acid and KLG is operated in such a way that an efficient separation process allows the majority of the KLG to be recycled for further conversion. The product stream from the separation process is then subjected to a recovery step to obtain crystalline L-ascorbic acid product.