Process for the conversion of sugars to lactic acid and 2-hydroxy-3-butenoic acid or esters thereof comprising a metallo-silicate material and a metal ion
A process for the preparation of lactic acid and 2-hydroxy-3-butenoic acid or esters thereof from a sugar in the presence of a metallo-silicate material, a metal ion and a solvent, wherein the metal ion is selected from one or more of the group consisting of potassium ions, sodium ions, lithium ions, rubidium ions and caesium ions.
1. A process for the preparation of lactic acid and 2-hydroxy-3-butenoic acid or esters thereof from a sugar in the presence of a metallo-silicate material, a metal ion and a solvent, said process comprising contacting the sugar with a metallo-silicate material, wherein the metal ion is selected from one or more of the group consisting of potassium ions, sodium ions, lithium ions, rubidium ions and caesium ions.
2. A process according to claim 1 , wherein the metal ion is obtainable by the addition to the process of one or more compounds selected from the group consisting of K 2 CO 3 , KNO 3 , KCl, potassium acetate (CH 3 CO 2 K), potassium lactate (CH 3 CH(OH)CO 2 K), Na 2 CO 3 , Li 2 CO 3 and Rb 2 CO 3 .
3. A process according to claim 1 , wherein the metallo-silicate material framework structure is selected from the group consisting of BEA, MFI, FAU, MOR, FER, MCM and SBA.
4. A process according to claim 1 , wherein the metallo-silicate material comprises an active metal selected from one or more of the group consisting of Sn, Ti, Pb, Zr, Ge and Hf.
5. A process according to claim 1 , wherein the metallo-silicate material is selected from the group consisting of Sn-BEA, Sn-MFI, Sn-FAU, Sn-MCM-41 and Sn-SBA-15.
6. A process according to claim 1 , wherein the sugar is selected from one or more of the group consisting of glucose, fructose, mannose, sucrose, xylose, erythrose, erythrulose, threose and glycolaldehyde.
7. A process according to claim 1 , wherein the solvent is selected from one or more of the group consisting of methanol, ethanol, 1-propanol, 1-butanol and water.
8. A process according to claim 1 , wherein the ester of lactic acid is methyl lactate or ethyl lactate.
9. A process according to claim 1 , wherein the yield of methyl lactate is equal to or greater than 69%.
10. A process according to claim 1 , wherein the metallo-silicate material is prepared using a post synthesis process.
11. A process according to claim 1 , wherein the metallo-silicate material is prepared by impregnating a de-aluminated or de-boronated zeotype material or mesoporous amorphous silicate material with an active metal.
12. A process according to claim 1 , wherein the metallo-silicate material is prepared by impregnating a de-aluminated or de-boronated zeotype material or mesoporous amorphous silicate material with an active metal and a metal ion.