PROCESS FOR THE HYDROFORMYLATION OF OLEFINS USING A COBALT PRE-CATALYST

Abstract

Process for the hydroformylation of olefins using a cobalt pre-catalyst.

Claims

1. Process comprising the process steps of: a) adding an olefin; b) adding a cobalt pre-catalyst, wherein the cobalt pre-catalyst is [Co(acac)(C.sub.4H.sub.8O.sub.2).sub.4].sup.+[BF.sub.4].sup.−; c) feeding in synthesis gas; d) heating the reaction mixture from a) to c), with conversion of the olefin to an aldehyde.

2. Process according to claim 1, wherein the olefin is selected from: ethene, propene, 1-butene, cis-2-butene, trans-2-butene, mixture of cis- and trans-2-butene, raffinate 1, raffinate 2, isobutene, 1-pentene, 2-pentene, 2-methyl-1-butene, 2-methyl-2-butene, 1-methylcyclohexene, tetramethylethene, 1-octene, 2-octenes, cyclooctene, di-n-butene, diisobutene, undecenes, dodecenes, triisobutene, tri-n-butene.

3. Process according to claim 1, wherein the olefin is selected from: 1-butene, cis-2-butene, trans-2-butene, isobutene, 1-pentene, 2-pentene, 1-octene, 2-octenes, di-n-butene, diisobutene, triisobutene, tri-n-butene.

4. Process according to claim 1, wherein the Co pre-catalyst is initially charged as a solution.

5. Process according to claim 4, wherein the olefin is added to the initially charged Co pre-catalyst solution.

6. Process according to claim 1, wherein synthesis gas is fed in in process step c) at a pressure in the range from 1 to 8 MPa (10 to 80 bar).

7. Process according to claim 1, wherein synthesis gas is fed in in process step c) at a pressure in the range from 4 to 6 MPa (40 to 60 bar).

8. Process according to claim 1, wherein the reaction mixture is heated in process step d) to a temperature in the range from 80° C. to 180° C.

9. Process according to claim 1, wherein the reaction mixture is heated in process step d) to a temperature in the range from 120° C. to 160° C.

Description

[0003] This object is achieved by a process according to claim 1.

[0004] Process comprising the process steps of:

[0005] a) adding an olefin;

[0006] b) adding a cobalt pre-catalyst, [0007] wherein the cobalt pre-catalyst is [Co(acac)(C.sub.4H.sub.8O.sub.2).sub.4].sup.+[BF.sub.4].sup.−;

[0008] c) feeding in synthesis gas;

[0009] d) heating the reaction mixture from a) to c), with conversion of the olefin to an aldehyde.

[0010] In this process, process steps a), b) and c) can be effected in any desired sequence.

[0011] In one variant of the process, the olefin is selected from:

[0012] ethene, propene, 1-butene, cis-2-butene, trans-2-butene, mixture of cis- and trans-2-butene, raffinate 1, raffinate 2, isobutene, 1-pentene, 2-pentene, 2-methyl-1-butene, 2-methyl-2-butene, 1-methylcyclohexene, tetramethylethene, 1-octene, 2-octenes, cyclooctene, di-n-butene, diisobutene, undecenes, dodecenes, triisobutene, tri-n-butene.

[0013] In one variant of the process, the olefin is selected from:

[0014] 1-butene, cis-2-butene, trans-2-butene, isobutene, 1-pentene, 2-pentene, 1-octene, 2-octenes, di-n-butene, diisobutene, triisobutene, tri-n-butene.

[0015] In one variant of the process, the cobalt pre-catalyst is initially charged as a solution.

[0016] In one variant of the process, the olefin is added to the initially charged cobalt pre-catalyst solution.

[0017] In one variant of the process, synthesis gas is fed in in process step c) at a pressure in the range from 1 to 8 MPa (10 to 80 bar).

[0018] In one variant of the process, synthesis gas is fed in in process step c) at a pressure in the range from 4 to 6 MPa (40 to 60 bar).

[0019] In one variant of the process, the reaction mixture is heated in process step d) to a temperature in the range from 80° C. to 180° C.

[0020] In one variant of the process, the reaction mixture is heated in process step d) to a temperature in the range from 120° C. to 160° C.

[0021] The invention is to be illustrated in detail hereinafter by a working example.

##STR00001##

[0022] A solution of the pre-catalyst (40.1 mL) is added to a 300 mL Premex autoclave equipped with sparging stirrer, and is charged with synthesis gas to 35 bar. The solution is heated up to 160° C. and the pressure is regulated to 50 bar. After 30 minutes, the temperature is lowered to 140° C. The olefin (1-octene) is now added to the catalyst solution by means of a syringe pump, and the reaction solution is stirred at 50 bar at 140° C. for 3 hours. The reaction mixture is then cooled to room temperature and the pressure is released. The yield is determined by gas chromatography.

[0023] The reaction was carried out using three different pre-catalysts.

[0024] Pre-catalysts (1) and (2) are comparative pre-catalysts.

[0025] Pre-catalysts:

[0026] (1) Co.sub.2(CO).sub.8

[0027] (2) Co(acac).sub.2

[0028] (3) [Co(acac)(C.sub.4H.sub.8O.sub.2).sub.4].sup.+[BF.sub.4].sup.−

[0029] Reaction conditions:

[0030] T=140° C., p(synthesis gas)=50 bar, t=3 h, olefin=1-octene

[0031] The experimental results are listed in the following Table:

TABLE-US-00001 Pre-catalyst Olefin [Co] (mM) T (° C.) t (h) Yield (%) (1) 1-Octene 1 140 3 62.7 (2) 1-Octene 1 140 3 66.9 (3)* 1-Octene 1 140 3 69.3 *process according to the invention

[0032] In the process according to the invention using pre-catalyst (3), a better yield was achieved than in the two comparative experiments.

[0033] As the working example shows, the object is achieved by the process according to the invention.