The starting material is cellulose, sucrose, starch or HFCS. When using sucrose, the glucose and fructose are split by a conventional chemical process step. The glucose is converted by an enzymatic process to obtain fructose purer than 99.8%.
Using chemocatalysis in a continuous reactor, 5-Hydroxymethylfurfural (HMF) is made from fructose in a quick reaction. Very high yields have been achieved. The next step is an oxidation of HMF directly connected to the previous step, without isolating HMF. Short process times and the avoidance of isolating the intermediate HMF are crucial to assure high FDCA yields.