Methods for converting cellulose to furanic products

1. A process for conversion of cellulose pulp to hydroxymethyl furfural, the process comprising:

separating a lignin-depleted hydrolysate stream comprising glucose, hydroxymethyl furfural, an organic acid, and water to thereby produce:

a first stream comprising the hydroxymethyl furfural, the organic acid, and water; and

a second stream comprising the glucose and water;

isomerizing the glucose in the second stream to thereby produce a fructose stream;

dehydrating fructose in the fructose stream to thereby produce a reaction product comprising hydroxymethyl furfural: and

recycling the reaction product, the recycling comprising introducing the reaction product from the dehydrating step to the separating step.

2. The process of claim 1 , wherein the separating further produces a third stream comprising water and cellobiose.

3. The process of claim 1 , wherein the lignin-depleted hydrolysate stream further comprises sodium ions, wherein the sodium ions are present in an amount not greater than 5% weight/weight.

4. The process of claim 1 , wherein the concentration of the glucose in the lignin-depleted hydrolysate stream is ≥6% weight/weight.

5. The process of claim 1 , wherein the concentration of the hydroxymethyl furfural in the lignin-depleted hydrolysate stream is ≤3% weight/weight.

6. The process of claim 1 , wherein the separating comprises simulated moving bed chromatography or sequential simulated moving bed chromatography.

7. The process of claim 6 , wherein the separating comprises a strong acid cation exchange resin.

8. The process of claim 1 , wherein the isomerizing comprising increasing the pH to at least 8.

9. The process of claim 8 , wherein the increasing the pH comprises adding an ionic liquid in hydroxide form.

10. The process of claim 1 , wherein the isomerizing comprises 0.5 to 10 hours of stirring at a temperature between 45 to 80° C.

11. The process of claim 1 , wherein the dehydrating comprises a strong acid cation resin.

12. The process of claim 11 , wherein the strong acid cation resin is a macroporous strong acid cation resin.

13. The process of claim 1 , wherein the fructose stream comprises fructose and glucose.

14. The process of claim 13 , wherein the dehydrating comprises converting at least 50% of the fructose to hydroxymethyl furfural, wherein at least 60% of the glucose is not converted to hydroxymethyl furfural.

15. The process of claim 13 , wherein the fructose stream comprises 4-10% glucose weight/weight and 1-4% fructose weight/weight.

16. The process of claim 1 , wherein the reaction product comprises 3-10% glucose weight/weight, ≤0.2% fructose weight/weight, and 1-3% hydroxymethyl furfural weight/weight.

17. The process of claim 1 , further comprising capturing the hydroxymethyl furfural from the first stream, the capturing comprising adsorbing on a non-functional polymeric resin the hydroxymethyl furfural from the first stream.

18. The process of claim 17 , further comprising recovering the captured hydroxymethyl furfural, the recovering comprising solvent desorption.

19. The process of claim 17 , wherein the capturing further comprises controlling the pH of the reaction product to be above the pKa of the organic acid.

20. The process of claim 17 , further comprising increasing the pH of the first stream prior to the capturing.

21. The process of claim 20 , wherein the increasing the pH comprises adding an ionic liquid in hydroxide form.

22. The process of claim 18 , wherein the solvent desorption comprises addition of a solution of a solvent and water to the non-functional polymeric resin.

23. The process of claim 22 , wherein the solvent is selected from ethyl acetate, methanol, ethanol, isopropanol, 1-butanol, 2-butanol, and combinations thereof.

24. The process of claim 1 , wherein the first stream comprises ≤5% weight/weight hydroxymethyl furfural.