Furfural process

Furfural yield and selectivity are maximized by reacting a 1 to 10 percent pentose 0.05 to 0.2 normal mineral acid aqueous solution in a plug flow reactor operated at a temperature between 220 DEG C. and 300 DEG C. The reaction residence time is short and is between 0.5 and 100 seconds. This special high severity plug flow reactor operation may be operated in any configuration to recover the furfural product. Two preferred arrangements are a single phase, pentose recycle operation in which the furfural is recovered by solvent extraction and distillation, and a two phase, solvent recycle operation in which solvent is added to the reactor and furfural is recovered from the solvent by distillation. In some embodiments, the solvent has a boiling point higher than the boiling point of furfural and the ratio of solvent to aqueous phase on a weight to weight basis is between 0.25 and 2.