Hydrogenation catalyst and process for production thereof by the use of uncalcined starting material

Abstract

The invention relates to a process for preparing a shaped CuAl catalyst body for the hydrogenation of organic compounds containing a carbonyl function. More particularly, the shaped catalyst body is suitable for the hydrogenation of aldehydes, ketones and of carboxylic acids or esters thereof, specifically of fatty acids or esters thereof, such as fatty acid methyl esters, to the corresponding alcohols such as butanediol. The present invention further relates to CuAl catalysts obtainable by the preparation process.

Claims

1. A process for producing a tableted shaped catalyst body, which comprises the steps of: (a) combining of (i) at least one aqueous solution of copper compounds, aluminum compounds and optionally transition metal compounds and (ii) at least one aqueous carbonate-containing solution to form a precipitate, isolation of the precipitate, optionally washing of the isolated precipitate and drying of the isolated precipitate to give a dried precipitate, and (b) tableting of the dried precipitate obtained in step (a), wherein step (b) comprises: (b1) calcination of dried precipitate obtained in step (a) at a temperature in the range from 250 to 900 C., to give a calcined precipitate, (b2) mixing of dried precipitate obtained in step (a) with calcined precipitate obtained in step (b1) in a weight ratio of dried precipitate to calcined precipitate in the range from 2:98 to 98:2, to give a mixture, and (b3) tableting of the mixture obtained in step (b2).

2. The process according to claim 1, wherein a lubricant is added to the uncalcined precipitate obtained from step (a) or to the mixture obtained from step (b2) in an amount of from 0.1 to 5% by weight, based on the total weight of the composition to be tableted, before tableting.

3. The process according to claim 2, wherein the lubricant is added in an amount of from 0.5 to 5% by weight, based on the total weight of the composition to be tableted.

4. The process according to claim 2, wherein the lubricant is graphite.

5. The process according to claim 2, wherein the lubricant is added in an amount of from 1 to 4% by weight, based on the total weight of the composition to be tableted.

6. The process according to claim 1, wherein the pore volume of the tableted shaped catalyst body, determined by the Hg intrusion method in accordance with DIN 66133, is from 0.1 to 0.6 cm.sup.3/g.

7. The process according to claim 1, which comprises the following step: (c) after-calcination of the tableted shaped catalyst body at a temperature in the range from 250 to 900 C., to give an after-calcined shaped catalyst body.

8. The process according to claim 7, wherein the pore volume of the after-calcined shaped catalyst body, determined by the Hg intrusion method in accordance with DIN 66133, is from 0.15 to 0.70 cm.sup.3/g.

9. The process according to claim 8, wherein the pore volume of the after-calcined shaped catalyst body, determined by the Hg intrusion method in accordance with DIN 66133, is from 0.17 to 0.50 cm.sup.3/g.

10. The process according to claim 8, wherein the pore volume of the after-calcined shaped catalyst body, determined by the Hg intrusion method in accordance with DIN 66133, is from 0.19 to 0.4 cm.sup.3/g.

11. The process according to claim 7, wherein the step (c) takes places at temperature of about 750 C.

12. The process according to claim 7, which comprises the following step: (d) reduction of the tableted shaped catalyst body obtained from step (b) and/or the after-calcined shaped catalyst body obtained from step (c) to give a reduced shaped catalyst body.

13. The process according to claim 12, wherein reduction is effected by means of hydrogen.

14. The process according to claim 12, wherein reduction is carried out at a temperature in the range from 150 C. to 400 C.

15. The process according to claim 12, wherein reduction is carried out over a period of from 1 hour to 10 days.

16. The process according to claim 12, wherein (a) the reduced shaped catalyst body is covered with a liquid with exclusion of air after reduction, where the liquid is selected from the group consisting of isodecanol, fatty alcohols, hexadecane, 2-ethylhexanol, propylene glycol and mixtures thereof, or (b) a mixture of an oxygen-containing gas and an inert gas, wherein the oxygen-containing gas is oxygen and the inert gas is argon or nitrogen is fed into the reduction reactor containing the reduced shaped catalyst body, where the concentration of oxygen in the mixture during introduction is from 0.001% by volume to 50% by volume and is increased from about 0.02% by volume to about 21% by volume.

17. The process according to claim 7, wherein the step (c) takes place at a temperature in the range from 300 to 750 C.

18. The process according to claim 7, wherein the step (c) takes place at temperature in the range of 600 to 750 C.

19. The process according to claim 12, wherein reduction is carried out at a temperature in the range from 180 C. to 250 C.

20. The process according to claim 12, wherein reduction is carried out at a temperature in the range from 190 C. to 210 C.

21. The process according to claim 12, wherein reduction is carried out at, a temperature of about 200 C.

22. The process according to claim 12, wherein reduction is carried out over a period of from 2 hours to 72 hours.

23. The process according to claim 12, wherein reduction is carried out over a period of from 24 to 48 hours.

24. The process according to claim 1, wherein the precipitate obtained in step (a) has a carbonate content of up to 20% by weight inclusive, based on the total weight of the dried precipitate obtained in step (a).

25. The process according to claim 1, wherein the copper compound is selected from the group consisting of copper, copper oxide (Cu.sub.2O and/or CuO), copper nitrate, copper sulfate, copper carbonate, copper hydroxocarbonate, copper acetate, copper halides copper chloride, copper bromide or copper iodide and mixtures thereof.

26. The process according to claim 1, wherein the aluminum compound is selected from the group consisting of aluminum, aluminum hydroxide, aluminum oxide hydrate (boehmite), alkali metal aluminates, aluminum oxide (Al.sub.2O.sub.3), aluminum nitrate, aluminum sulfate, aluminum halides and mixtures thereof.

27. The process according to claim 1, wherein the transition metal compound is selected from the group consisting of Zn, Ti, Mn, Ni, Cr, Fe, Co, Mo, Ce and Zr and mixtures thereof.

28. The process according, to claim 1, wherein the carbonate-containing solution is obtained using at least one alkali metal carbonate, alkaline earth metal carbonate and/or ammonium carbonate and/or at least one alkali metal hydrogen carbonate, alkaline earth metal hydrogen carbonate and/or ammonium hydrogen carbonate.

29. The process according to claim 1, wherein step (b1) calcination of dried precipitate obtained in step (a) at a temperature in the range from 300 to 750 C., to give a calcined precipitate.

30. The process according to claim 1, wherein step (b1) calcination of dried precipitate obtained in step (a) at a temperature in the range from 600 to 750 C., to give a calcined precipitate.

31. The process according to claim 1, wherein the weight ratio of dried precipitate to calcined precipitate is in the range of from 10:90 to 90:10 to give a mixture.

32. The process according to claim 1, wherein the weight ratio of dried precipitate to calcined precipitate is in the range of from 15:85 to 85:15 to give a mixture.

33. The process according to claim 1, wherein the weight ratio of dried precipitate to calcined precipitate is in the range of from 20:80 to 50:50 to give a mixture.

34. The process according to claim 1, wherein the pore volume of the tableted shaped catalyst body, determined by the Hg intrusion method in accordance with DIN 66133, is from 0.13 to 0.40 cm.sup.3/g.

35. The process according to claim 1, wherein the pore volume of the tableted shaped catalyst body, determined by the Hg intrusion method in accordance with DIN 66133, is from 0.15 to 0.25 cm.sup.3/g.

36. The process according to claim 1, wherein the precipitate obtained in step (a) has a carbonate content range from 5% by weight to 18% by weight, based on the total weight of the dried precipitate obtained in step (a).

37. The process according to claim 1, wherein the precipitate obtained in step (a) has a carbonate content in the range from 6% by weight to 15% by weight, based on the total weight of the dried precipitate obtained in step (a).

38. The process according to claim 1, wherein the precipitate obtained in step (a) has a carbonate content in the range from 8 to 12% by weight, based on the total weight of the dried precipitate obtained in step (a).

39. The process according to claim 1, wherein the copper compound is selected from the group consisting of copper oxide, copper nitrate, copper chloride, copper carbonate, copper hydroxocarbonate, copper acetate, copper sulfate and mixtures thereof.

40. The process according to claim 1, wherein the aluminum compound is selected from the group consisting of aluminum nitrate, aluminum hydroxide, aluminum oxide hydrate, aluminum chloride, sodium aluminate, aluminum oxide and mixtures thereof.

41. The process according to claim 1, wherein the transition metal compound is selected from the group consisting of Mn, Zn, Ce, Zr and mixtures thereof.

42. The process according to claim 1, wherein the transition metal compound is from among compounds of Mn.

43. The process according to claim 1, wherein the carbonate-containing solution is obtained using sodium carbonate and/or sodium hydrogen carbonate.

44. A process for producing a tableted shaped catalyst body, which comprises the steps of: (a) combining of (i) at least one aqueous solution of copper compounds, aluminum compounds and optionally transition metal compounds and (ii) at least one aqueous carbonate-containing solution to form a precipitate, isolation of the precipitate, optionally washing of the isolated precipitate and drying of the isolated precipitate to give a dried precipitate, and (b) tableting of the dried precipitate obtained in step (a), wherein the precipitate obtained in step (a) contains at least 5% by weight of Cu hydroxocarbonate.

45. A process for producing a tableted shaped catalyst body, which comprises the steps of: (a) combining of (i) at least one aqueous solution of copper compounds, aluminum compounds and optionally transition metal compounds and (ii) at least one aqueous carbonate-containing solution to form a precipitate, isolation of the precipitate, optionally washing of the isolated precipitate and drying of the isolated precipitate to give a dried precipitate, (b) tableting of the dried precipitate obtained in step (a); (c) after-calcination of the tableted shaped catalyst body at a temperature in the range from 250 to 900 C., to give an after-calcined shaped catalyst body wherein the pore volume of the tableted shaped catalyst body, determined by the Hp intrusion method in accordance with DIN 66133, is from 0.1 to 0.6 cm.sup.3/g; and (d) reduction of the tableted shaped catalyst body obtained from step (b) and/or the after-calcined shaped catalyst body obtained from step (c) to give a reduced shaped catalyst body, wherein (a) the reduced shaped catalyst body is covered with a liquid with exclusion of air after reduction, where the liquid is isodecanol.

46. A process for producing a tableted shaped catalyst body, which comprises the steps of: (a) combining of (i) at least one aqueous solution of copper compounds, aluminum compounds and optionally transition metal compounds and (ii) at least one aqueous carbonate-containing solution to form a precipitate, isolation of the precipitate, optionally washing of the isolated precipitate and drying of the isolated precipitate to give a dried precipitate, (b) tableting of the dried precipitate obtained in step (a), (c) after-calcination of the tableted shaped catalyst body at a temperature in the range from 250 to 900 C., to give an after-calcined shaped catalyst body, wherein the pore volume of the tableted shaped catalyst body, determined by the Hg intrusion method in accordance with DIN 66133, is from 0.1 to 0.6 cm.sup.3/g, and (d) reduction of the tableted shaped catalyst body obtained from step (b) and/or the after-calcined shaped catalyst body obtained from step (c) to give a reduced shaped catalyst body, wherein (a1) the reduced shaped catalyst body is covered with a liquid with exclusion of air after reduction, where the liquid is selected from the group consisting of isodecanol, fatty alcohols, hexadecane, 2-ethylhexanol, propylene glycol and mixtures thereof, or (b1) a mixture of an oxygen-containing gas and an inert gas, wherein the oxygen-containing gas is oxygen and the inert gas is argon or nitrogen, is fed into the reduction reactor containing the reduced shaped catalyst body, where the concentration of oxygen in the mixture during introduction is from 0.001% by volume to 50% by volume and is increased from about 0.02% by volume to about 21% by volume.

47. A process for producing a tableted shaped catalyst body, which comprises the steps of: (a) combining of (i) at least one aqueous solution of copper compounds, aluminum compounds and optionally transition metal compounds and (ii) at least one aqueous carbonate-containing solution to form a precipitate, isolation of the precipitate, optionally washing of the isolated precipitate and drying of the isolated precipitate to give a dried precipitate, and (b) tableting of the dried precipitate obtained in step (a) wherein the precipitate obtained in step (a) contains from 10 to 80% by weight, of Cu hydroxocarbonate.

48. A process for producing a tableted shaped catalyst body, which comprises the steps of: (a) combining of (i) at least one aqueous solution of copper compounds, aluminum compounds and optionally transition metal compounds and (ii) at least one aqueous carbonate-containing solution to form a precipitate, isolation of the precipitate, optionally washing of the isolated precipitate and drying of the isolated precipitate to give a dried precipitate, and (b) tableting of the dried precipitate obtained in step (a), wherein the precipitate obtained in step (a) contains from 15 to 70% by weight, of Cu hydroxocarbonate.

Description

DESCRIPTION OF THE FIGURES

(1) FIG. 1 shows the pore radius distribution, measured using the Hg intrusion method in accordance with DIN 66133, of catalyst 1A as per example 5 after after-calcination but before reduction.

(2) FIG. 2 shows the pore radius distribution, measured by the Hg intrusion method in accordance with DIN 66133, of catalyst 1A as per example 5 after after-calcination and reduction by means of 5% by volume of hydrogen in nitrogen at 200 C. for 4 hours.

EXAMPLES

(3) The invention is illustrated by the following, nonlimiting examples. Even when these examples describe specific embodiments of the invention, they serve merely to illustrate the invention and should not be interpreted as restricting the invention in any way. As a person skilled in the art will know, numerous modifications can be made to these embodiments without going outside the scope of protection of the invention as defined by the accompanying claims.

(4) Determination of Physical Parameters

(5) The physical parameters described here are, unless indicated otherwise, determined as follows:

(6) Conductivity is determined in accordance with DIN 38404, part 8.

(7) Lateral compressive strength is determined in accordance with DIN EN 1094-5.

(8) Remaining loss on ignition is determined in accordance with DIN EN 196-2.

(9) Pore volume and pore radius distribution are determined by the Hg intrusion method in accordance with DIN 66133.

(10) Carbonate content is determined in accordance with DIN ISO 10693.

Example 1 (Production of the Uncalcined Material)

(11) The production of the uncalcined material is carried out via precipitation of the metal nitrates by means of sodium carbonate to form the carbonates thereof, and the precipitate is subsequently filtered off, washed and spray dried.

(12) Solution 1 is produced from 617 g of Cu(NO.sub.3).sub.2.3H.sub.2O, 106 g of Mn(NO.sub.3).sub.2.4H.sub.2O, 875 g of Al(NO.sub.3).sub.3.9H.sub.2O and 5 l of H.sub.2O. Solution 2 is produced from 850 g of Na.sub.2CO.sub.3 and 3.8 l of H.sub.2O. The two solutions are heated to 80 C. and stirred. They are subsequently metered into a precipitation vessel. The pH in the precipitation vessel is 6.8. The volume flows of solutions 1 and 2 are set so that this pH is established. As soon as the two solutions have been consumed, the precipitate formed is filtered off and washed with water. The filter cake is then resuspended in about 1 l of water and spray dried. The resulting dried but still uncalcined powder is the starting material for the further preparations.

Example 2 (Production of the Calcined Material)

(13) The calcined material is produced by calcining the uncalcined dried powder from example 1 at 750 C. in a convection furnace for 2 hours. The remaining loss on ignition of the calcined material at 1000 C. (LOI) is about 5% by weight.

Example 3 (Production of the Comparative Catalyst)

(14) The comparative catalyst is produced by mixing 100 g of calcined powder produced as per example 2 with 3% by weight of graphite and subsequently tableting the mixture to form shaped bodies having a diameter of about 3 mm and a height of about 3 mm. The lateral compressive strength of the comparative catalyst is 85 N, determined in accordance with DIN EN 1094-5.

Example 4 (Production of Catalyst 1)

(15) To produce catalyst 1, 75 g of calcined powder (from example 2) are mixed with 25 g of uncalcined powder (from example 1) and 3 g of graphite and tableted to form shaped bodies having a diameter of about 3 mm and a height of about 3 mm. The lateral compressive strength is 85 N.

Example 5 (Production of Catalyst 1a)

(16) Catalyst 1A is produced in a manner analogous to catalyst 1, but the pellets are calcined at 750 C. in a convection furnace for 2 hours after tableting.

Example 6 (Production of Catalyst 2)

(17) To produce the catalyst 2, 50 g of calcined powder (from example 2) are mixed with 50 g of uncalcined powder (from example 1) and 3 g of graphite and tableted to form shaped bodies having a diameter of about 3 mm and a height of about 3 mm. The lateral compressive strength is 75 N.

Example 7 (Production of Catalyst 2a)

(18) Catalyst 2A is produced in a manner analogous to catalyst 2, but the pellets are calcined at 750 C. in a convection furnace for 2 hours after tableting.

Example 8 (Production of Catalyst 3)

(19) To produce the catalyst 3, 25 g of calcined powder (from example 2) are mixed with 75 g of uncalcined powder (from example 1) and 3 g of graphite and tableted to form shaped bodies having a diameter of about 3 mm and a height of about 3 mm. The lateral compressive strength is 75 N.

Example 9 (Production of Catalyst 3a)

(20) Catalyst 3A is produced in a manner analogous to catalyst 3, but the pellets are calcined at 750 C. in a convection furnace for 2 hours after tableting.

Example 10 (Production of Catalyst 4)

(21) To produce the catalyst 4, 100 g of uncalcined powder (from example 1) and 3 g of graphite are mixed and tableted to form shaped bodies having a diameter of about 3 mm and a height of about 3 mm. The lateral compressive strength is 70 N.

Example 11 (Production of Catalyst 4a)

(22) Catalyst 4A is produced in a manner analogous to catalyst 4, but the pellets are calcined at 750 C. in a convection furnace for 2 hours after tableting.

Example 12 (Activity Measurements)

(23) The activity of the catalysts in respect of the hydrogenation of methyl esters of fatty acids (FAME) is examined. An electrically heated fixed-bed reactor having a reactor volume of 25 ml is used for this purpose. Methyl laurate (C12-methyl ester) is used for the test. To evaluate the conversion of the ester and the selectivity to the fatty alcohol or the formation of bi-products, the reaction product formed is analyzed by gas chromatography. The conversion is calculated from the molar amount of the ester used and the remaining molar amount of ester in the product.

(24) For the analysis by gas chromatography, 6.0000 g of the product formed are mixed with 0.2000 g of 5-nonanol (internal standard). The sample is subsequently analyzed twice by means of a gas chromatograph.

(25) Equipment Used:

(26) GC: Agilent 7890A with FID

(27) Column: ZB-1, 60 m0.25 mm from Phenomenex

(28) Software: EZ Chrom Elite Version 3.3.2 SP1

(29) Test Conditions in the Hydrogenation of Methyl Laurate: Temperature points: 240, 180, 160 C., Pressure: 280 bar GHSV (H.sub.2): 20000 h.sup.1 LHSV (ester): 1.4 h.sup.1

(30) Table 1 shows the values for the conversions of C12-methyl ester obtained by the above-described method at 240 C., 180 C. and 160 C. for the comparative catalyst and the catalysts 1 to 4 and 1A to 4A (examples 4 to 11). The improved activity on the catalysts 1 to 4 and 1A to 4A compared to the comparative catalyst can clearly be seen, in particular at 160 C. As the values for the catalysts 1A, 2A, 3A and 4A show, a renewed improvement in the activity is obtained by means of an after-calcination.

(31) TABLE-US-00001 TABLE 1 Conversions of C12-methyl ester at 240, 180 and 160 C. Ratio of uncalcined Conversion of C12-methyl material to ester [%] Catalysts calcined material 240 C. 180 C. 160 C. Comparative 0/100 97.1 81 62.5 catalyst Catalyst 1 25/75 97.9 83.9 72.4 Catalyst 1A 25/75, after- 99.5 98 81.8 calcined Catalyst 2 50/50 97.9 83 70 Catalyst 2A 50/50, after- 98.8 95.2 77.3 calcined Catalyst 3 75/25 97.8 82 67 Catalyst 3A 75/25, after- 98.3 93.5 75.6 calcined Catalyst 4 100/0 97.6 81 66 Catalyst 4A 100/0, after- 98.1 90.1 73.3 calcined

(32) Table 2 shows the values for the carbonate content and the pore volume of the various catalysts after tableting but before an after-calcination, after tableting and after-calcination and also after tableting, after-calcination and reduction. Reduction was carried out at 200 C. for 4 hours using 5% by volume of hydrogen in nitrogen. The pore volume was determined by the mercury intrusion method in accordance with DIN 66133. Particularly after reduction, the shaped catalyst bodies according to the invention have a higher pore volume than the comparative catalyst.

(33) TABLE-US-00002 TABLE 2 Carbonate content and pore volume Pore volume [cm.sup.3/g] Carbonate After After After content [%] tableting calcination reduction Comparative 0.15 0.2 catalyst Catalyst 1 2.3 0.13 0.24* 0.29 Catalyst 2 4.5 0.19 0.33* 0.46 Catalyst 3 6.8 0.24 0.36* 0.5 Catalyst 4 8.9 0.3 0.37* 0.52 *values correspond to the catalysts 1A to 4A

(34) The analytical data show that the carbonate content of the catalysts varies as a function of the proportion of uncalcined material.

(35) It can be seen from table 1 that the catalysts produced according to the invention have a significantly increased conversion of methyl laurate compared to the comparative catalyst. This increase could be observed at all three temperatures selected, 160 C., 180 C. and 240 C. The proportion of unreacted C12-methyl ester could be reduced to less than one fifth (from 2.9% in the case of the comparative catalyst to 0.5% in the case of catalyst 1A).

(36) In summary, it can therefore be said that an improvement in the economics, in particular an increase in the conversion to the target product, is achieved by means of the catalyst of the invention.