GAS-PHASE PROCESS FOR THE CONVERSION OF GLYCOLALDEHYDE WITH AN AMINATING AGENT

Abstract

A process for the conversion of glycolaldehyde with an aminating agent in the presence of hy-5 drogen and of a catalyst, wherein the conversion is carried out in the gas phase.

Claims

1.-13. (canceled)

14. A process for the conversion of glycolaldehyde with an aminating agent in the presence of hydrogen and of a catalyst, wherein the conversion is carried out in the gas phase and in the presence of one or more solvents wherein the weight fraction of water in the one or more solvents present during the process is in the range of 50 to 100 percent by weight and wherein the aminating agent is a compound of formula (I) ##STR00002## in which R.sup.1, R.sup.2 are hydrogen (H), alkyl such as C.sub.1-20-alkyl, cycloalkyl such as C.sub.3-12-cycloalkyl, alkoxyalkyl such as C.sub.2-30-alkoxyalkyl, dialkylaminoalkyl such as C.sub.3-30-dialkylaminoalkyl, aryl, aralkyl such as C.sub.7-20-aralkyl, and alkylaryl such as C.sub.7-20-alkylaryl, or together are —(CH.sub.2).sub.j—X—(CH.sub.2).sub.k—, X is CH.sub.2, CHR.sup.3, oxygen (O), sulfur (S) or NR.sup.3, R.sup.3 is hydrogen (H), alkyl such as C.sub.1-4-alkyl, alkylphenyl such as C.sub.7-40-alkylphenyl, j, k are each integers from 1 to 4.

15. The process according to claim 14, wherein the glycolaldehyde is provided to the process in the gaseous form, and wherein the aminating agent is provided to the process in the gaseous form.

16. The process according to claim 15, wherein the glycolaldehyde is provided to the process in the gaseous form by evaporation of glycolaldehyde from mixtures of glycolaldehyde and one or more solvents in which the content of glycolaldehyde is in the range of 2 to 50 percent by weight, based on the total weight of glycolaldehyde and the one or more solvents.

17. The process according to claim 15, wherein the aminating agent is provided to the process in its gaseous form by evaporation of the aminating in its pure form or by evaporation of mixtures of aminating agent in one or more solvents.

18. The process according to claim 15, wherein the glycolaldehyde is provided to the process in the gaseous form by feed gaseous effluents obtained from the manufacture of glycolaldehyde.

19. The process according to claim 18, wherein the glycolaldehyde in its gaseous form is obtained from the hydrous thermolysis of sugars or pyrolysis of wood.

20. The process according to claim 15, wherein the aminating agent which is provided to the process is transferred into its gaseous form in the absence of glycolaldehyde and glycolaldehyde which is provided to the process is transferred into gaseous form in the absence of aminating agent.

21. The process according to claim 15, wherein the gaseous aminating agent and the gaseous glycolaldehyde are provided separately to the process or wherein the gaseous aminating agent and the gaseous glycolaldehyde are mixed to obtain a mixed feed stream

22. The process according to claim 14, wherein the proportion of glycolaldehyde which is present during the process is in the range of 1 to 50 percent by volume.

23. The process according to claim 14, wherein the molar ratio of glycolaldehyde to aminating agent which is present during the process is in the range to 1:1 to 100 and/or wherein the molar ratio of hydrogen to glycolaldehyde which is present during the process is in the range of 10:1 to 500:1.

24. The process according to claim 14, wherein the proportion of solvent which is present during the process is in the range of 1 to 50 percent by volume.

25. The process according to claim 14, wherein the conversion of glycolaldehyde is carried out at a pressure of 0.01 to 200 bar and/or at a temperature of 120 to 600° C.

26. The process according to claim 14, wherein the aminating agent is a compound of formula (I) ##STR00003## in which R.sup.1, R.sup.2 are hydrogen (H), alkyl such as C.sub.1-20-alkyl, cycloalkyl such as C.sub.3-12-cycloalkyl, alkoxyalkyl such as C.sub.2-30-alkoxyalkyl, dialkylaminoalkyl such as C.sub.3-30-dialkylaminoalkyl, aryl, aralkyl such as C.sub.7-20-aralkyl, and alkylaryl such as C.sub.7-20-alkylaryl, or together are —(CH.sub.2).sub.j—X—(CH.sub.2).sub.k—, X is CH.sub.2, CHR.sup.3, oxygen (O), sulfur (S) or NR.sup.3, R.sup.3 is hydrogen (H), alkyl such as C.sub.1-4-alkyl, alkylphenyl such as C.sub.7-40-alkylphenyl, j, k are each integers from 1 to 4.

Description

EXAMPLES

[0160] The invention is illustrated by the following examples:

Example 1 (Comparative Example): Liquid Phase Conversion

[0161] Before introduction into the autoclave, the passivated catalysts A and B were activated as follows:

[0162] In run 1, catalyst A was reduced at 240° C. for 8 h at a partial hydrogen pressure of 1 bar. In run 2, catalyst B was reduced at 200° C. for 8 h at a partial hydrogen pressure of 1 bar.

[0163] Subsequently, an electrically heated 300 mL autoclave with a mechanical magnet-coupled stirrer was charged with an aqueous solution of glycolaldehyde (7.5 wt. % or 15 wt. %) under an inert gas atmosphere. Dimethylamine, according to the molar ratio specified in Table 1, was metered in and the mixture was heated to the reaction temperature of 160° C. On attainment of this temperature, the reactor was pressurized to 100 bar by the injection of hydrogen.

[0164] The product stream was analyzed by gas chromatography and is reported in Table 1:

TABLE-US-00001 TABLE 1 Run GA-Concentration Ratio MEG DMEOA TMEDA Total No (wt.-%) Catalyst DMA/GA (%) (%) (%) (%) 1 7.5 A 19:1 0 2 1 3 2 15 B 9_1 0 2 1 3

Example 2: Gas Phase Conversion

[0165] A double-walled glass reactor of 1000 mm length, diameter 40 mm with oil heating, a quartz frit at the bottom, an inlet for liquid and gaseous feeds at the top connected to a pump and gaseous feeds (H.sub.2, optionally N.sub.2 and aminating agent) measured via rotameters, was set up vertically and the outlet (bottom) was connected to a collecting flask. This was mounted with a water cooler and an additional dry-ice cooler. The off-gas was connected to a laboratory hood vent. Into the center of the reactor, a glass tube was put from the top down and a flexible thermocouple was introduced into this tube. The reactor was filled in three layers. First, 400 mL of Raschig rings composed of steel wire mesh (diameter 5 mm) were loaded onto the quartz frit. Then a catalyst (100 mL, see Table 2) was introduced. The height of the catalyst bed was about 80 mm. Above the catalyst bed, 450 mL of Raschig rings were loaded that served as an evaporator and heating zone for the liquid feed and the gas feed. The feed inlet of the aminating agent was positioned centrally about 10 cm above the catalyst bed via a steel capillary that was fixed to the thermocouple. The Raschig ring bed between the inlet of the aminating agent feed and the catalyst ensured thorough mixing of DMA and gaseous GA.

[0166] The catalyst was activated prior to the experiment in a stream of hydrogen at a temperature of 240° C.

[0167] The tubular reactor was heated up to the reaction temperature indicated in Table 2.

[0168] Gaseous DMA was metered from a bottle and introduced via the capillary into the reactor. The amount of DMA in the gas stream corresponds to the amount specified in Table 2.

[0169] GA solution was directly fed on top of the evaporator bed in the reactor. Hydrogen was fed into the reactor from the top of the evaporator bed downwards through the reactor at 1 bar. The GA solution evaporated through the combined action of the heating and constant entrainment by hydrogen and the evaporator bed served as a heater for the GA/hydrogen stream. The amount of GA in the gas stream corresponds to the amount specified in Table 2. The concentration of the aqueous GA-solution, from which the GA is evaporated is also given in Table 2.

[0170] The combined gas stream of GA and water, hydrogen and aminating DMA passed over the catalyst bed and was partially condensed in the two coolers described above. The condensed material was collected in the collecting flask. Liquid samples were withdrawn regularly from the flask.

[0171] The gas hourly space velocity (GHSV) is also given in Table 2.

[0172] The composition of the liquid sample was determined by gaschromatography yielding the mass fractions of the major components. Taking into account the amount of condensed product stream and the mass of the glycolaldehyde feed, the yields of the major value products ethylene glycol (MEG), dimethylethanolamine (DMEOA) and tetramethylethylenediamine (TMEDA) were calculated. The results are reported in Table 2.

TABLE-US-00002 TABLE 2 Catalyst Run GA-Concentration Temperature Ratio Ratio Load MEG DMEOA TMEDA Total No (wt.-%) Catalyst (° C.) DMA/GA H2/GA (kgL/h) (%) (%) (%) (%) 1 7.5 A 160 19:1 191:1  0.06 0 47 26 73 2 15 A 160 19:1 92:1 0.06 0 33 38 71 3 15 A 160 39:1 92:1 0.05 0 21 47 68 4 15 B 170 19:1 91:1 0.06 0 64 8 71 5 15 B 160 19:1 91:1 0.06 0 66 4 70 6 15 B 160 19:1 91:1 0.06 0 65 3 68 7 15 B 160  9:1 91:1 0.06 0 60 5 65 8 15 B 160 36:1 84:1 0.12 0 71 3 74 9 15 B 160 18:1 45:1 0.12 0 68 4 72 10 15 B 160 12:1 56:1 0.17 1 67 2 70 11 15 B 165 12:1 56:1 0.17 1 74 4 76

[0173] Catalyst A was a catalyst comprising 45 percent by weight of Cu and 10 percent by weight of Ni on an alumina support. The preparation of the catalyst was carried out according to the Example in EP-B1-2346602.

[0174] Catalyst B was catalyst comprising 56 percent by weight of Cu, based on the total weight of the catalyst, on an alumina support, as used in Example 1 of EP-A2-0514692

[0175] The comparison of Example 1 with Example 2 shows that the liquid phase conversion of glycolaldehyde with an aminating agent in water delivers only small yields of desired products. The gas phase conversion gives significantly higher yields.