Overview of Biorefineries based on Co-Production of Furfural, Existing Concepts and Novel Developments

At Delft University of Technology theoretical and experimental research is carried out towards selective production of furfural from renewable biomass. Furfural is an interesting molecule that has been identified as a platform chemical for a multitude of chemical products and fuel (additives). Acidic biomass hydrolysis and subsequent dehydration of the obtained C-5 sugar xylose leads to furfural. The reaction selectivity is a point of concern for reactor design, as furfural can further react to loss products. The residue of this process mainly consists of the remaining main biomass constituents, cellulose and lignin. Mineral matter is to a large extent extracted to the acid in the primary hydrolysis. This implies that the residue has the potential to be a better feed-stock for thermo-chemical conversion, as e. g. alkali and chlorine species-now extracted-potentially cause different types of problems (slagging, fouling, agglomeration etc.). An interesting option for example might be to convert this improved feedstock into synthesis gas via a gasification process, which then needs to be conditioned and upgraded for the production of green transportation fuels. In this line, a new biorefinery generation is created, which selectively uses the hemi-cellulose part of biomass. An analysis is presented towards current (integrated) concepts for novel, improved furfural production process. This paper presents some current process concepts and a novel continuous process design.