| CPC C07C 29/84 (2013.01) | 11 Claims |

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1. A process for the production of a high purity first diol, selected from the group consisting of C2 to C7 diols from a product stream comprising two or more C2 to C7 diols, said process comprising the steps of:
(i) providing the product stream to a first distillation column;
(ii) providing an extractant selected from the group of C3 to C6 sugar alcohols and mixtures thereof to the first distillation column;
(iii) operating the first distillation column at a temperature in the range of from 50 to 250° C. and a pressure in the range of from 0.1 to 400 kPa to obtain a first bottoms stream comprising at least a first diol and the extractant and a first top stream comprising a mixture comprising one or more C2 to C7 diols;
(iv) providing the first bottoms stream to a second distillation column operating at a temperature in the range of from 50 to 250° C. and a pressure in the range of from 0.1 to 400 kPa to obtain a second top stream comprising the first diol and diols with atmospheric boiling points at least 10° C. higher than the first diol, and
(v) providing the second top stream to a third distillation column to obtain a third top stream comprising the first diol in a purity higher than 99.5% by weight, wherein the product stream comprises 0.1 to 10 wt % of diols with atmospheric boiling points at least 10° C. higher than the first diol, calculated upon the total weight of C2 to C7 diols in the product stream.
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