US 8,013,192 B2 · Process for preparing 1,3-propanediol

Abstract

The invention provides a process for preparing 1,3-alkanediols, such as 1,3-propanediol (PDO), from 3-hydroxyaldehydes, such as 3-hydroxypropanal (HPA), comprising providing a mixture of 3-hydroxyaldehydes in an organic solvent; extracting into an aqueous liquid a major portion of the 3-hydroxyaldehydes to provide an aqueous phase comprising 3-hydroxyaldehydes in greater concentration than the concentration of 3-hydroxyaldehydes in the 3-hydroxyaldehyde mixture, and an organic phase; separating the aqueous phase from the organic phase; contacting the aqueous phase with hydrogen in the presence of a hydrogenation catalyst to provide a hydrogenation product mixture comprising 1,3-alkanediols and water; separating water from the 1,3-alkanediols using a multi-effect evaporation scheme; recycling water containing about 50 wt % or less 1,3-propanediol based upon the total amount of 1,3-propanediol and water to the extraction stage; and recovering 1,3-alkanediols.

Claims28

Dependent claims

A process for preparing a 1,3-alkanediol from a 3-hydroxyaldehyde, comprising providing a mixture of a 3-hydroxyaldehyde in an organic solvent;

extracting into an aqueous liquid a major portion of the 3-hydroxyaldehyde to provide an aqueous phase comprising the 3-hydroxyaldehyde in greater concentration than the concentration of the 3-hydroxyaldehyde in the 3-hydroxyaldehyde mixture, and an organic phase;
separating the aqueous phase from the organic phase;
contacting the aqueous phase with hydrogen in the presence of a hydrogenation catalyst to provide a hydrogenation product mixture comprising a 1,3-alkanediol and water;
separating water from the 1,3-alkanediol using a multi-effect evaporation scheme;
recycling water containing 50 wt % or less of the 1,3-alkanediol based upon the total amount of 1,3-alkanediol and water to the extraction stage;
and recovering the 1,3-alkanediol.

3 more elements

A process for preparing 1,3-propanediol comprising the steps of:

(a) providing a mixture of 3-hydroxypropanal in an essentially non water miscible organic solvent;
(b) adding an aqueous liquid to said mixture and extracting into said aqueous liquid a major portion of the 3-hydroxypropanal to provide an aqueous phase comprising 3-hydroxypropanal in greater concentration than the concentration of 3-hydroxypropanal in the 3-hydroxypropanal mixture, and an organic phase;
(c) separating the aqueous phase from the organic phase;
(d) contacting the aqueous phase with hydrogen in the presence of a hydrogenation catalyst to provide a hydrogenation product mixture comprising 1,3-propanediol, water, and light ends;
(e) separating water from the hydrogenation product mixture by introducing the hydrogenation product mixture into a first thermal separation stage and heating it to produce a first overhead hot vapor stream comprising water and light ends and a first bottoms thermal separation product mixture stream comprising water and 1,3-propanediol in greater concentration than the concentration of 1,3-propanediol in the hydrogenation product mixture;
(f) introducing the first bottoms thermal separation product mixture stream into a second thermal separation stage to produce a second overhead hot vapor stream comprising water and light ends and a second bottoms thermal separation product mixture stream comprising water and 1,3-propanediol in greater concentration than the concentration of 1,3-propanediol in the first bottoms thermal separation product mixture stream;
(g) optionally repeating step f) at least once to produce a third or successive overhead hot vapor stream comprising water and light ends and a third or successive bottoms thermal separation product mixture stream comprising water and 1,3-propanediol in greater concentration than the concentration of 1,3-propanediol in the preceding bottoms thermal separation product mixture stream;
(h) removing the heat from at least one of the overhead hot vapor streams and providing said heat for use in at least one of the other steps of the process for preparing 1,3-propanediol;
(i) recycling the water from the overhead hot vapor streams to step (b);
and
(j) recovering 1,3-propanediol.

8 more elements

A process for preparing 1,3-propanediol comprising the steps of:

(a) providing a mixture of 3-hydroxypropanal in an essentially non water miscible organic solvent;
(b) adding an aqueous liquid to said mixture and extracting into said aqueous liquid a major portion of the 3-hydroxypropanal to provide an aqueous phase comprising 3-hydroxypropanal in greater concentration than the concentration of 3-hydroxypropanal in the 3-hydroxypropanal mixture, and an organic phase;
(c) separating the aqueous phase from the organic phase;
(d) contacting the aqueous phase with hydrogen in the presence of a hydrogenation catalyst to provide a hydrogenation product mixture comprising 1,3-propanediol, water, and light ends;
(e) separating water from the hydrogenation product mixture by introducing the hydrogenation product mixture into a first thermal separation stage and heating it to produce a first overhead hot vapor stream comprising water and light ends and a first bottoms thermal separation product mixture stream comprising water and 1,3-propanediol in greater concentration than the concentration of 1,3-propanediol in the hydrogenation product mixture;
(f) introducing the first bottoms thermal separation product mixture stream into a second thermal separation stage to produce a second overhead hot vapor stream comprising water and light ends and a second bottoms thermal separation product mixture stream comprising water and 1,3-propanediol in greater concentration than the concentration of 1,3-propanediol in the first bottoms thermal separation product mixture stream;
(g) optionally repeating step f) at least once to produce a third or successive overhead hot vapor stream comprising water and light ends and a third or successive bottoms thermal separation product mixture stream comprising water and 1,3-propanediol in greater concentration than the concentration of 1,3-propanediol in the preceding bottoms thermal separation product mixture stream;
(h) removing the heat from at least one of the overhead hot vapor streams and providing said heat for use in at least one of the other steps of the process for preparing 1,3-propanediol;
(i) introducing the last bottoms thermal separation product mixture stream to a crude 1,3-propanediol separator to produce a crude 1,3-propanediol overhead stream comprising water, 1,3-propanediol, and light ends, and a crude 1,3-propanediol bottoms stream comprising water and 1,3-propanediol in greater concentration than the concentration of 1,3-propanediol in the last bottoms thermal separation product mixture stream;
(j) introducing the crude 1,3-propanediol overhead stream into a light ends separator to remove light ends from the water and 1,3-propanediol, thereby producing a concentrated water stream containing 50 wt % or less 1,3-propanediol based upon the total amount of 1,3-propanediol and water;
(k) recycling the concentrated water stream to step b);
and
(l) recovering 1,3-propanediol from the crude 1,3-propanediol bottoms stream.

10 more elements

A process for preparing 1,3-propanediol comprising the steps of:

(a) providing a mixture of 3-hydroxypropanal in an essentially non water miscible organic solvent;
(b) adding an aqueous liquid to said mixture and extracting into said aqueous liquid a major portion of the 3-hydroxypropanal to provide an aqueous phase comprising 3-hydroxypropanal in greater concentration than the concentration of 3-hydroxypropanal in the 3-hydroxypropanal mixture, and an organic phase;
(c) separating the aqueous phase from the organic phase;
(d) contacting the aqueous phase with hydrogen in the presence of a hydrogenation catalyst to provide a hydrogenation product mixture comprising 1,3-propanediol, water, and light ends;
(e) separating water from the hydrogenation product mixture by introducing the hydrogenation product mixture into a thermal separation stage and heating it to produce an overhead hot vapor stream comprising water and light ends and a bottoms thermal separation product mixture stream comprising water and 1,3-propanediol in greater concentration than the concentration of 1,3-propanediol in the hydrogenation product mixture;
(f) removing the heat from the overhead hot vapor stream and providing said heat for use in a crude 1,3-propanediol distillation column wherein the overhead hot vapor stream is condensed;
(g) introducing the bottoms thermal separation product mixture stream to the crude 1,3-propanediol separator to produce a crude 1,3-propanediol overhead stream comprising water, 1,3-propanediol, and light ends, and a crude 1,3-propanediol bottoms stream comprising water and 1,3-propanediol in greater concentration than the concentration of 1,3-propanediol in the bottoms thermal separation product mixture stream;
(h) introducing the crude 1,3-propanediol overhead stream into a light ends separator to remove light ends from the water and 1,3-propanediol, thereby producing a concentrated water stream containing 50 wt % or less 1,3-propanediol based upon the total amount of 1,3-propanediol and water;
(i) recycling the concentrated water stream to step b);
and
(j) recovering 1,3-propanediol from the crude 1,3-propanediol bottoms stream.

8 more elements

Dependencies are inferred from the claim text.

Process for preparing 1,3-propanediol

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Process for preparing 1,3-propanediol

Life of this patent

Abstract

Claims28