Process for the dehydration of oxygenated compounds

Patent metadata

Field	Value
Publication number	US-10894750-B2
Application number	US-201615540399-A
Country	US
Kind code	B2
Filing date	Feb 22, 2016
Priority date	Feb 23, 2015
Publication date	Jan 19, 2021
Grant date	Jan 19, 2021

Abstract

The present invention relates to a process for the dehydration of at least one oxygenated compound, preferably selected from saturated alcohols, unsaturated alcohols, diols, ethers, in the presence of at least one dehydration catalyst selected from cerium oxide (CeO2), aluminium oxide (γ-Al2O3), aluminium silicate, silica-aluminas (SiO2—Al2O3), aluminas, zeolites, sulfonated resins, ion-exchange resins, metal oxides (for example, lanthanum oxide, zirconium oxide, tungsten oxide, thallium oxide, magnesium oxide, zinc oxide); of at least one basic agent selected from ammonia (NH3), or from inorganic or organic compounds containing nitrogen capable of developing ammonia (NH3) during said dehydration process; and, optionally, of silica (SiO2), or of at least one catalyst for the dissociation of ammonia (NH3) selected from catalysts comprising silica (SiO2), preferably of silica (SiO2).

First claim

The invention claimed is:

1. A process of dehydrating at least one oxygenated compound, the process comprising:
feeding to a reactor a mixture comprising at least one oxygenated compound selected from the group consisting of a saturated alcohol and an unsaturated alcohol and at least one basic agent selected from the group consisting of ammonia and a nitrogen-containing compound which forms ammonia during the dehydration,
wherein the mixture passes through a first catalytic bed and subsequently through a second catalytic bed, and
wherein the first catalytic bed consists of silica and the second catalytic bed comprises at least one dehydration catalyst selected from the group consisting of cerium oxide, aluminum oxide, aluminum silicate, silica-alumina, a zeolite, lanthanum oxide, zirconium oxide, tungsten oxide, thallium oxide, magnesium oxide, and zinc oxide.

2. The process of claim 1 , wherein the oxygenated compound comprises a saturated alcohol having from 1 to 25 carbon atoms.

3. The process of claim 1 , wherein the oxygenated compound comprises an unsaturated alcohol having from 2 to 20 carbon atoms.

4. The process of claim 1 , wherein the at least one oxygenated compound is provided in either (i) anhydrous form, or (ii) in mixture with water wherein the water is present in an amount greater than or equal to 0.005% by weight, based on a total weight of the mixture.

5. The process of claim 1 , wherein the oxygenated compound is derived from a fermentation of one or more sugars obtained from biomass.

6. The process of claim 1 , wherein the oxygenated compound is derived from a fermentation of one or more sugars obtained from guayule or from thistle.

7. The process of claim 1 , wherein the basic agent is at least one selected from the group consisting of: ammonia in the gaseous form; ammonium hydroxide; urea; ammonium carbonate or bicarbonate; a primary, secondary or tertiary amine, aliphatic or aromatic, having a boiling point ranging from −8° C. to 250° C.; and a heterocyclic compound comprising a nitrogen atom.

8. The process of claim 1 , wherein when the basic agent is ammonia, the ammonia is present in an amount of from 0.005% by weight to 4% by weight, based on a total amount of the oxygenated compound and optional organic compounds present, and alternatively when the basic agent is a nitrogen-containing compound which forms ammonia upon dehydration, the ammonia formed is present in an amount of 0.005% by weight to 4% by weight, based on a total amount of the oxygenated compound and optional organic compounds present.

9. The process of claim 1 , wherein the process is performed adiabatically, isothermally, or a combination of both in a continuous reactor, which is a fixed-bed or a fluid-bed reactor.

10. The process of claim 9 , wherein the reactor operates at:
a temperature ranging from 190° C. to 500° C.; and/or
a pressure ranging from 0.3 bara (bar absolute) to 3.5 bara (bar absolute).

11. The process of claim 9 , wherein the oxygenated compound, optionally with water, is fed to the reactor operating at a WHSV ranging from 0.5 h −1 to 30 h −1 .

12. A process comprising dehydrating at least one oxygenated compound, the process comprising:
feeding to a reactor a mixture comprising at least one oxygenated compound selected from the group consisting of a saturated alcohol, an unsaturated alcohol, and a diol and at least one basic agent that is an inorganic nitrogen-containing compound which forms ammonia during the dehydration,
wherein the mixture passes through a first catalytic bed and subsequently through a second catalytic bed, and
wherein the first catalytic bed consists of silica and the second catalytic bed comprises at least one dehydration catalyst selected from the group consisting of ammonium phosphate and a metal phosphate.

13. A process comprising:
(a) dehydrating 1,3-butanediol optionally in a mixture with water to obtain a product comprising an unsaturated alcohol, in the presence of
(i) at least one dehydration catalyst selected from the group consisting of cerium oxide, aluminum oxide, aluminum silicate, silica-alumina, a zeolite, lanthanum oxide, zirconium oxide, tungsten oxide, thallium oxide, magnesium oxide, and zinc oxide;
(ii) an inorganic nitrogen-containing compound which forms ammonia during the dehydration; and
(iii) optionally silica;

(b) distilling the product to obtain the unsaturated alcohol; and
(c) dehydrating a mixture comprising a nitrogen-containing compound which forms ammonia during the dehydration and the unsaturated alcohol to produce 1,3-butadiene, in the presence of
(i′) a first dehydration catalyst in a first catalyst bed, wherein the first dehydration catalyst consists of silica; and
(ii′) a second dehydration catalyst in a second catalyst bed, wherein the second dehydration catalyst is selected from the group consisting of aluminum oxide, aluminum silicate, silica-alumina, a zeolite, lanthanum oxide, and zirconium oxide, wherein the mixture comprising the unsaturated alcohol passes through the first catalyst bed and subsequently through the second catalyst bed.

Assignees

• Versalis Spa

Inventors

• Vecchini Nicola
• Girotti Gianni

Classifications

• B01J35/40

  characterised by dimensions, e.g. grain size (in a colloidal state B01J35/23; crystallite size B01J35/77) · CPC title

• B01J37/031

  Precipitation · CPC title

• C07C1/24 Primary

  by elimination of water · CPC title

• C07C2521/12

  Silica and alumina · CPC title

• C07C29/60 Primary

  by elimination of -OH groups, e.g. by dehydration (C07C29/34 takes precedence) · CPC title