Patent ID: 9481626
Filing Date: 2016-11-01
CPC Classification: C07C

Claim Text:
1. A continuous process for producing formic acid from a cellulose-containing material using a first reactor and a second reactor, the process comprising continuously supplying the cellulose-containing material into the first reactor; hydrolyzing the cellulose-containing material in the first reactor in the presence of a mineral acid in an amount of 1 to 10% wt of the cellulose-containing material in the first reactor for a first time period, at a first temperature of 195 to 235 degrees C. and a first pressure effective to hydrolyze at least a portion of the cellulose-containing material to form an intermediate hydrolysate comprising one or more sugars; continuously transferring the intermediate hydrolysate from the first reactor and delivering the intermediate hydrolysate to a second reactor; hydrolyzing the intermediate hydrolysate in the second reactor for a second time period that is greater than the first time period, at a second temperature of 195 degrees C. or less and a second pressure to form a hydrolysate product comprising formic acid and levulinic acid in the second reactor, wherein the second temperature and the second pressure are selected to maintain the intermediate hydrolysate as a fluid in the second reactor; and continuously removing the formic acid in a vapor from the second reactor in an amount that provides a molar ratio of the formic acid to the levulinic acid of at least 0.8.