METHOD AND CATALYST FOR THE PRODUCTION OF 1,3-BUTADIENE FROM ETHANOL

Abstract

The present invention is concerned with a catalyst for the conversion of ethanol to 1,3-butadiene comprising a component A selected from the list consisting of zeolite, silicon dioxide, aluminium oxide, or any combination thereof; and a component B.sub.cat comprising a mixed metal oxide, a catalyst precursor for the preparation of a catalyst for the conversion of ethanol to 1,3-butadiene comprising a component A selected from the list consisting of zeolite, silicon dioxide, aluminium oxide, or any combination thereof; and a component B.sub.pre comprising a layered double hydroxide (LDH) as well as a process for the conversion of ethanol to 1,3-butadiene, in which said catalyst is used.

Claims

1. A catalyst for the conversion of ethanol to 1,3-butadiene comprising i) component A, which is selected from a list consisting of zeolite, silicon dioxide, aluminum oxide, or any combination thereof; and ii) component B.sub.cat comprising a mixed metal oxide.

2. The catalyst according to claim 1, wherein the weight ratio of component A to component B.sub.cat is in the range from 1:0.05 to 1:2.5.

3. The catalyst according to claim 1, wherein the mixed metal oxide is a layered double oxide (LDO).

4. The catalyst according to claim 1, wherein the catalyst has a core-shell structure, wherein the core of the core-shell structure comprises component A and the shell of the core-shell-structure comprises component B.sub.cat.

5. A catalyst precursor for the preparation of a catalyst for the conversion of ethanol to 1,3-butadiene comprising i) component A, which is selected from a list consisting of zeolite, silicon dioxide, aluminum oxide, or any combination thereof; and ii) component B.sub.pre comprising a layered double hydroxide (LDH).

6. The catalyst precursor according to claim 5, wherein the weight ratio of component A to component B.sub.pre is in the range from 1:0.1 to 1 :5.

7. The catalyst precursor according to claim 5, wherein the catalyst precursor has a core-shell structure, wherein the core of the core shell structure comprises component A and the shell of the core-shell-structure comprises component B.sub.pre.

8. The catalyst precursor according to claim 5, wherein the layered double hydroxide (LDH) comprises a first metal DM and a second metal TM.

9. The catalyst precursor according to claim 8, wherein the first metal DM is selected from a list consisting of Li, Ca, Mg, Zn, Fe, Co, Cu, Ni and combinations thereof.

10. The catalyst precursor according to claim 8, wherein the second metal TM is selected from a list consisting of Al, Ga, In, Y, Fe, Co, Mn, Cr, Ti, V, La, Sn, Zr, and combinations thereof.

11. The catalyst precursor according to claim 5, wherein component A is a zeolite selected from the group consisting of ZSM-5, X-zeolite, Y-zeolite, USY-zeolite, beta-zeolite, MCM-22, ferrierrite, chabazite, and combinations thereof.

12. The catalyst precursor according to claim 11, wherein the zeolite has a molar ratio of Si to Al in the range from 1:1 to 5000:1.

13. A process for producing 1,3-butadiene comprising contacting an ethanol stream with a catalyst according to claim 1.

14. Use of a catalyst according to claim 1 for the conversion of ethanol to 1,3-butadiene.

15. Use of a catalyst precursor according to claim 5 for the preparation of a catalyst for the conversion of ethanol to 1,3-butadiene.

16. The catalyst according to claim 1, wherein the layered double oxide (LDO) comprises a first metal DM and a second metal TM.

17. The catalyst according to claim 16, wherein the first metal DM is selected from a list consisting of Li, Ca, Mg, Zn, Fe, Co, Cu, Ni and combinations thereof.

18. The catalyst according to claim 16, wherein the second metal TM is selected from a list consisting of Al, Ga, In, Y, Fe, Co, Mn, Cr, Ti, V, La, Sn, Zr, and combinations thereof.

19. The catalyst according to claim 1, wherein component A is a zeolite selected from the group consisting of ZSM-5, X-zeolite, Y-zeolite, USY-zeolite, beta-zeolite, MCM-22, ferrierrite, chabazite, and combinations thereof.

20. The catalyst according to claim 19 or the catalyst precursor according to claim 11, wherein the zeolite has a molar ratio of Si to Al in the range from 1:1 to 5000:1.

Description

FIGURES

[0122] FIG. 1: XRD patterns of pure SiO.sub.2 and the core-shell SiO.sub.2—Mg.sub.3Al—CO.sub.3 LDH (IE1)

[0123] FIG. 2: SEM and TEM images of SiO.sub.2 spheres

[0124] FIG. 3: TEM image of Zeolite ZA

[0125] FIG. 4: SEM and TEM images of the core-shell SiO.sub.2—Mg.sub.3Al—LDH with SiO.sub.2 spheres as core (IE1)

[0126] FIG. 5: SEM and TEM images of the core-shell Zeolite ZA—Mg.sub.3Al—LDH (IE2) with Zeolite ZA as core

[0127] FIG. 1 shows the XRD patterns of pure SiO.sub.2 and the core-shell SiO.sub.2—Mg.sub.3Al—CO.sub.3 LDH. By this image it can be shown that the core-shell SiO.sub.2—Mg.sub.3Al—CO.sub.3 LDH samples were successfully synthesized since characteristic peaks of Mg.sub.3Al—CO.sub.3 LDH can be observed, which are the sharp and intense (003), (006), (009), (015), (018), (110), and (113) reflections at 2θ=11.50, 22.90, 34.74, 39.13, 46.28, 60.46, and 61.80. SiO.sub.2 can be found at 2θ=22.6.

[0128] FIG. 4 shows the SEM and TEM images of the core-shell SiO.sub.2—Mg.sub.3Al—LDH with core SiO.sub.2 spheres which shows the formation of a LDH shell over silica sphere cores which is shown in FIG. 2.

[0129] FIG. 5 shows the SEM and TEM images of the core-shell Zeolite ZA—Mg.sub.3Al—LDH with core Zeolite ZA which shows the formation of a LDH shell over Zeolite ZA cores which is shown in FIG. 3.

Measurement Methods

[0130] a) The X-ray powder diffraction (XRD)

[0131] The X-ray powder diffraction (XRD) patterns of a sample were identified using a X-ray powder diffractometer (Rikagu TTRAX III) with a monochromator and Cu-Kα radiation at λ=0.15405 nm. The 2-theta was ranged from 5° to 80° with the scan speed of 3°/min and the scan step of 0.02°.

b) Scanning Electron Microscopy (SEM)

[0132] Scanning Electron Microscopy (SEM) analysis was performed on a JEOL JSM 6610 scanning electron microscope. Particles were dispersed in water and cast onto a clean silica wafer. Energy dispersive X-ray spectroscopy (EDX), also carried out on this instrument, was used to determine the relative quantities of constituent elements on the surface of the sample.

c) Transmission Electron Microscopy (TEM)

[0133] Transmission Electron Microscopy (TEM) analysis was performed on a JEOL 2100 Plus microscope with an accelerating voltage of 200 kV. Particles were dispersed in water or ethanol using sonication and subsequently cast onto copper grids coated with carbon film and left to dry.

d) Gas Chromatography (GC)

[0134] The gaseous products were analysed by gas chromatography (Agilent Technologies 6890 Network GC system) using a HP-PLOT Al.sub.2O.sub.3 column (50 m×0.32 mm ID and 20 μm film thickness) equipped with a flame ionization detector (FID) to determine hydrocarbon gases. The GC operating conditions were set as followed:

[0135] Initial temperature: 40° C. (10 min holding time)

[0136] Ramp 1: [0137] Heating rate: 10° C./min [0138] Final temperature: 120° C. and 10 min holding time

[0139] Ramp 2: [0140] Heating rate: 5° C./min [0141] Final temperature: 180° C. (10 min holding time)

e) Gas Chromatography-Mass Spectrometry, Time of Flight (GC-TOF)

[0142] The liquid products were analysed using a gas chromatograph equipped with a mass spectrometer of a time of flight type (GC×GC-TOF/MS), Agilent 7890. Helium was used as the carrier gas, and nitrogen was used in the cooling system. The conditions were set as followed: [0143] Initial temperature: 40° C. (2 min holding time) [0144] Heating rate: 2.5° C./min [0145] Final temperature: 250° C. (5 min holding time) [0146] Split ratio: 1:25

EXPERIMENTAL PART

Materials

[0147] ZA is a ZSM-5 zeolite having a Si:Al ratio of 250-700.

[0148] ZB is a ZSM-5 zeolite-having a Si:Al ratio of 800-1300.

Comparative Example 1 (CE1): Mg.SUB.3.Al—CO.SUB.3 .LDH (Chemical Formula: Mg.SUB.0.75.Al.SUB.0.25.(OH).SUB.2.(CO.SUB.3.).SUB.0.125.)

[0149] Mg.sub.3Al—CO.sub.3 LDH was synthesized by adding 700 ml of an aqueous metal precursor solution containing 1.575 mol Mg(NO.sub.3).sub.2⋅6H.sub.2O and 0.525 mol Al(NO.sub.3).sub.3⋅9H.sub.2O to 700 ml of a solution of 0.315 mol Na.sub.2CO.sub.3. The pH of the resulting solution was controlled at pH 10 by dropwise adding of 4 M NaOH under vigorous stirring. Subsequently, the obtained solution was aged for 3 h at a temperature of approximately 25° C. After aging, the precipitated solid compound was filtered off the solution and washed with deionized water until a pH=7 of the filtrate was reached. Finally, the wet cake of solid compound was dried in an oven at 110° C. overnight. Comparative Example 1 represents an example having no core, but only a shell of Mg.sub.3Al—CO.sub.3 LDH

Comparative Example 2 (CE2): Cu.SUB.0.5.Ni.SUB.0.2.Mg.SUB.2.3.Al—CO.SUB.3 .LDH (Chemical Formula: Cu.SUB.0.125.Ni.SUB.0.05.Mg.SUB.0.575.Al.SUB.0.25.(OH).SUB.2.(CO.SUB.3.).SUB.0.125.)

[0150] Cu.sub.0.5Ni.sub.0.2Mg.sub.2.3Al—CO.sub.3 LDH was synthesized by adding 700 ml of an aqueous metal precursor solution containing 1.208 mol Mg(NO.sub.3).sub.2⋅6H.sub.2O, 0.2625 mol Cu(NO.sub.3).sub.2⋅6H.sub.2O, 0.105 mol Ni(NO.sub.3).sub.2⋅6H.sub.2O and 0.525 mol Al(NO.sub.3).sub.3⋅9H.sub.2O to 700 ml of a solution of 0.315 mol Na.sub.2CO.sub.3. The pH of the resulting solution was controlled at pH 10 by dropwise adding of 4 M NaOH under vigorous stirring. Subsequently, the obtained solution was aged for 3 h at a temperature of approximately 25° C. After aging the precipitated solid compound was filtered off the solution and washed with deionized water until a pH=7 of the filtrate was reached. Finally, the wet cake of solid compound was dried in an oven at 80° C. overnight. Comparative Example 2 represents an example having no core, but only a shell of Cu.sub.0.5Ni.sub.0.2Mg.sub.2.3Al—CO.sub.3 LDH.

Inventive Example 1 (IE1): Core SiO.SUB.2.—Shell Mg.SUB.3.Al—CO.SUB.3 .LDH (Chemical Formula: Mg.SUB.0.75.Al.SUB.0.25.(OH).SUB.2.(CO.SUB.3.).SUB.0.125.)

[0151] Silica having a spherical shape with 500 nm particle diameter was used as the core for the synthesis of IE1. IE1 was synthesized by a co-precipitation method as explained in the following: 5 g silica having the shape of a sphere were dispersed in 1000 ml deionized water using an ultrasound treatment for 30 min. Subsequently, 27 mmol Na.sub.2CO.sub.3 were added and further treated by ultrasound for 5 min. Then 1000 ml of an aqueous metal precursor solution containing 81 mmol Mg(NO.sub.3).sub.2⋅6H.sub.2O and 27 mmol Al(NO.sub.3).sub.3⋅9H.sub.2O ml were added to the mixture of deionized water, silica and Na.sub.2CO.sub.3 under vigorous stirring resulting in a suspension. The pH of the suspension was controlled at pH 10 by dropwise adding of 1 M NaOH. After aging for 120 min under stirring at a temperature of approximately 25° C., the obtained solid compound was filtered off the suspension using vacuum filtration and washed using deionized water until a pH=7 of the filtrate was reached. Finally, the wet cake of the solid compound was dried in an oven at 110° C. overnight.

Inventive Example 2 (IE2): Core Zeolite ZA—Shell Mg.SUB.3.Al—CO.SUB.3 .LDH (Chemical Formula: Mg.SUB.0.75.Al.SUB.0.25.(OH).SUB.2.(CO.SUB.3.).SUB.0.125.)

[0152] Also IE2 was synthesized using a co-precipitation method: 5 g of zeolite ZA were dispersed in 1000 ml deionized water using an ultrasound treatment for 30 min. Subsequently, 27 mmol Na.sub.2CO.sub.3 were added and further treated by ultrasound for 5 min. Then the 1000 ml of an aqueous metal precursor solution containing 81 mmol Mg(NO.sub.3).sub.2⋅6H.sub.2O and 27 mmol Al(NO.sub.3).sub.3⋅9H.sub.2O ml were added to the mixture of deionized water, zeolite ZA and Na.sub.2CO.sub.3 under vigorous stirring resulting in a suspension. The pH of the suspension was controlled at pH 10 by dropwise adding of 1 M NaOH. After aging for 120 min under stirring at a temperature of approximately 25° C., the obtained solid compound was filtered off the suspension using vacuum filtration and washed using deionized water until pH=7 of the filtrate was reached. Finally, the wet cake of the solid compound was dried in an oven at 110° C. overnight.

Inventive Example 3 (IE3): Core SiO.SUB.2.—Shell Mg.SUB.3.Al.SUB.0.9.Zr.SUB.0.1.—CO.SUB.3 .LDH (Chemical Formula Mg.SUB.0.75.Al.SUB.0.225.Zr.SUB.0.025.(OH).SUB.2.(CO.SUB.3.).SUB.0.125.)

[0153] Silica having a spherical shape with 500 nm particle diameter was used as the core for the synthesis of IE3. IE3 was again synthesized by a co-precipitation method: 5 g of silica having the shape of a sphere were dispersed in 1000 ml deionized water using an ultrasound treatment for 30 min. Subsequently, 27 mmol Na.sub.2CO.sub.3 were added and further treated by ultrasound for 5 min. Then 1000 ml of an aqueous metal precursor solution containing 81 mmol Mg(NO.sub.3).sub.2⋅6H.sub.2O, 24.3 mmol Al(NO.sub.3).sub.3⋅9H.sub.2O and 2.7 mmol ZrN.sub.2O.sub.7⋅9H.sub.2O were added to the mixture of deionized water, silica and Na.sub.2CO.sub.3 under vigorous stirring resulting in a suspension. The pH of the suspension was controlled at pH 10 by dropwise adding of 1 M NaOH. After aging for 120 min under stirring at a temperature of approximately 25° C., the obtained solid compound was filtered off the suspension using vacuum filtration and washed using deionized water until pH=7 of the filtrate was reached. Finally, the wet cake of the solid compound was dried in an oven at 80° C. overnight.

Inventive Example 4 (IE4)—Core Zeolite ZB—Shell Cu.SUB.0.5.Ni.SUB.0.2.Mg.SUB.2.3.Al—CO.SUB.3 .LDH (Chemical Formula: Cu.SUB.0.125.Ni.SUB.0.05.Mg.SUB.0.575.Al.SUB.0.25.(OH).SUB.2.(CO.SUB.3.).SUB.0.125.)

[0154] IE4 was also synthesized by the co-precipitation method: 5 g of zeolite ZB were dispersed in 1000 ml deionized water using an ultrasound treatment for 30 min. Subsequently, 27 mmol Na.sub.2CO.sub.3 and further treated by ultrasound for 5 min. Then 1000 ml of an aqueous metal precursor solution containing 13.5 mmol Cu(NO.sub.3).sub.2⋅6H.sub.2O, 5.4 mmol Ni(NO.sub.3).sub.2⋅6H.sub.2O, 62.1 mmol Mg(NO.sub.3).sub.2⋅6H.sub.2O and 27 mmol Al(NO.sub.3).sub.3⋅9H.sub.2O were added the mixture of deionized water, zeolite ZB and Na.sub.2CO.sub.3 under vigorous stirring resulting in a suspension. The pH of the suspension was controlled at pH 10 by dropwise adding of 1 M NaOH. After aging for 120 min under stirring at a temperature of approximately 25° C., the obtained solid compound was filtered off the suspension using vacuum filtration and washed using deionized water until pH=7 of the filtrate was reached. Finally, the wet cake of the solid compound was dried in an oven at 80° C. overnight.

Conversion of Ethanol to 1,3-butadiene

[0155] The catalysts precursor as produced in CE1 to CE2 and IE1 to IE4 were calcined at a temperature of 500° C. transforming the LDHs of the catalyst precursor to LDOs and subsequently contacted with an ethanol feed stream at a temperature of 350° C., under atmospheric pressure, and at a weight hourly space velocity (WHSV) of 1.55 h.sup.−1. The reaction was carried out for 3 h (time on stream). The products obtained were divided in liquid and gaseous products. The liquid products were analyzed using a gas chromatograph equipped with a mass spectrometer of a time of flight type (GC×GC-TOF/MS). The gaseous products were analyzed by gas chromatography (Agilent Technologies 6890 Network GC system) using a HP-PLOT Al.sub.2O.sub.3 column (50 m×0.32 mm ID and 20 μm film thickness) equipped with a flame ionization detector (FID) to determine hydrocarbon gases.

[0156] The results of the conversion reaction of ethanol to 1,3 butadiene at a time on stream for 3 h are displayed in Table 1.

TABLE-US-00001 TABLE 1 Time on Stream: 3 h Conditions Results Temperature WHSV 1,3-butadiene yield Ethylene yield Catalyst Activity No. Component A Component B.sub.cat [° C.] [h.sup.−1] [% wt] [% wt] [g.sub.1,3-BD g.sub.cat.sup.−1 h.sup.−1] CE1 — Mg.sub.3Al 350 1.55 12.4 20.1 0.19 IE1 SiO.sub.2 Mg.sub.3Al 350 1.55 20.3 12.4 0.32 IE2 Zeolite ZA Mg.sub.3Al 350 1.55 35.8 7.5 0.56 IE3 SiO.sub.2 Mg.sub.3Al.sub.0.9Zr.sub.0.1 350 1.55 37.9 9.5 0.59 CE2 — Cu.sub.0.5Ni.sub.0.2Mg.sub.2.3Al 350 1.55 15.3 15.4 0.24 IE4 Zeolite ZB Cu.sub.0.5Ni.sub.0.2Mg.sub.2.3Al 350 1.55 38.2 13.4 0.59

[0157] In Table 1 the % 1,3-butadiene yield and the catalyst activity after performing the reaction are the key parameters to indicate the catalyst performance.

[0158] The catalyst of the CE1 consists of Mg and Al and does not contain component A (i.e. any core). While this catalyst at least converts ethanol to 1,3-butadiene, it is found that the1,3 butadiene yield and the catalyst activity are lowest for CE1 in comparison to CE2 and IE1 to IE 4. Hence, the catalyst composition of CE1 is used as baseline for all remaining examples CE2 and IE1 to IE4. The catalyst of CE2 has improved performance compared to the catalyst of CE1. The LDH of CE2 comprises Cu and Ni together with Mg and Al. Furthermore, the catalyst of CE2 does not contain component A (i.e. any core). The 1,3 butadiene yield and the catalyst activity are slightly increased in comparison to CE1.

[0159] The inventive catalysts according to IE1 to IE4 comprise both a component A and a component B.sub.cat. It is found that their 1,3-butadiene yields and the catalyst activities are significantly increased in comparison to CE1 and CE2.