Production of glycolaldehyde by thermolytic fragmentation

1. A process for the production of glycolaldehyde comprising the step of thermolytic fragmentation of a salt-depleted carbohydrate feedstock comprising at least 20 wt/wt % mono- and/or di-saccharide(s) and less than 200 ppm salts to obtain the glycolaldehyde,

wherein the pH of the salt-depleted carbohydrate feedstock is below 6.

2. The process according to claim 1 , wherein the salt-depleted carbohydrate feedstock has a color above 75 ICUMSA units (IU).

3. The process according to claim 1 , wherein the salt-depleted carbohydrate feedstock comprises more than 30 wt/wt % mono-saccharide(s).

4. The process according to claim 1 , wherein the salt-depleted carbohydrate feedstock comprises a total amount of heavy metals of more than 5 mg/kg.

5. The process according to claim 1 , wherein the salt-depleted carbohydrate feedstock has a residue on ignition above 0.5 wt/wt %.

6. A process for the production of glycolaldehyde comprising the step of thermolytic fragmentation of a salt-depleted carbohydrate feedstock comprising at least 20 wt/wt % mono- and/or di-saccharide(s) and less than 200 ppm salts to obtain the glycolaldehyde,

wherein the salt-depleted carbohydrate feedstock is of non-food grade purity as defined by the Food Chemicals Codex,

wherein the pH of the salt-depleted carbohydrate feedstock is below 6.

7. The process according to claim 1 , wherein the process comprises a prior step of salt-depleting a crude carbohydrate material to obtain a salt-depleted carbohydrate feedstock comprising less than 200 ppm salts.

8. The process according to claim 7 , wherein the crude carbohydrate material is salt-depleted by means of ion-exchange.

9. The process according to claim 7 , wherein the crude carbohydrate material is selected from cane sugar, cane sugar syrup, cellulose hydrolysate, starch hydrolysate, hemi-cellulose hydrolysate, corn syrup, sugar beet syrup; or a mixture thereof.

10. The process according to claim 1 , wherein the salt-depleted carbohydrate feedstock comprises less than 180 ppm salts.

11. The process according to claim 1 , wherein the salt-depleted carbohydrate feedstock is injected into a thermolytic fragmentation unit in the form of an aqueous solution.

12. A process for the production of glycolaldehyde from a crude carbohydrate material comprising at least 20 wt/wt % mono- and/or di-saccharide(s), said process comprising the steps of:

a. removing salt from said crude carbohydrate material, to provide a salt-depleted carbohydrate feedstock comprising less than 200 ppm salts;

b. performing thermolytic fragmentation on the salt-depleted carbohydrate feedstock so as to obtain glycolaldehyde,

wherein the pH of the salt-depleted carbohydrate feedstock is below 6.

13. A system for continuously performing the process according to claim 12 , said system comprising an ion-exchange unit having an inlet and an outlet, and a thermolytic fragmentation unit having inlet and outlet, wherein the outlet of said ion-exchange unit is fluidly connected to the inlet of said thermolytic fragmentation unit.

14. The process according to claim 12 , wherein the salt-depleted carbohydrate feedstock is of non-food grade purity as defined by the Food Chemicals Codex.

15. The process according to claim 1 , wherein the salt-depleted carbohydrate feedstock comprises one or more impurities selected from the group consisting of arsenic, lead, sulfate, sulfur dioxide, and 5-(hydroxymethyl)furfural.

16. The process according to claim 1 , wherein the salt-depleted carbohydrate feedstock comprises 5-(hydroxymethyl)furfural.

17. The process according to claim 12 , wherein the salt-depleted carbohydrate feedstock comprises one or more impurities selected from the group consisting of arsenic, lead, sulfate, sulfur dioxide, and 5-(hydroxymethyl)furfural.

18. The process according to claim 12 , wherein the salt-depleted carbohydrate feedstock comprises 5-(hydroxymethyl)furfural.