Process to prepare higher ethylene amines and ethylene amine derivatives

Abstract

The present invention relates to a process to prepare ethylene amines of the formula NH.sub.2(C.sub.2H.sub.4NH).sub.pH wherein p is at least 3 or derivatives thereof wherein one or more units NHC.sub.2H.sub.4NH may be present as a cyclic ethylene urea unit or between two units NHC.sub.2H.sub.4NH a carbonyl moiety is present, by reacting an ethanolamine-functional compound, an amine-functional compound in the presence of a carbon oxide delivering agent, wherein the molar ratio of carbon oxide delivering agent to amine-functional compound is at least 0.6 to 1.

Claims

1. A process of preparing (i) ethylene amines of the formula: NH.sub.2(C.sub.2H.sub.4NH).sub.pH wherein p is at least 3, (ii) derivatives thereof wherein one or more NHC.sub.2H.sub.4NH units are present as a cyclic ethylene urea unit ##STR00010## and/or (iii) derivatives thereof wherein a carbonyl moiety is present between two NHC.sub.2H.sub.4NH units, said process comprising the following steps: (a) reacting an ethanolamine-functional compound and an amine-functional compound in the presence of a carbon oxide delivering agent to obtain a mixture of products, at least some of which products are said derivatives thereof wherein one or more units NHC.sub.2H.sub.4NH are present as a cyclic ethylene urea unit, wherein for said reacting the molar ratio of carbon oxide delivering agent to amine-functional compound is at least 0.8:1; and (b) converting at least some of said derivatives thereof wherein one or more units NHC.sub.2H.sub.4NH are present as a cyclic ethylene urea unit to the corresponding ethylene amines; wherein: the ethanolamine functional compound contains a hydroxyl group linked via an ethylene group to an amine group, or its carbamate equivalent, or the ethanolamine functional compound is UAEEA (the urea of aminoethylethanolamine); the amine functional compound contains no alcohol groups, and contains at least two primary amine groups and optionally more primary, secondary and/or tertiary amine groups, wherein the amine groups are linked to one another via ethylene groups, and optionally by a carbonyl moiety; and the carbon oxide delivering agent is carbon dioxide or an organic compound selected from urea, linear and cyclic alkylene ureas, mono- or di-substituted alkylene ureas, alkyl and dialkyl ureas, linear and cyclic carbamates and organic carbonates, and derivatives or precursors thereof selected from carbonate salts, bicarbonate salts and carbamic acids and their salts.

2. The process of claim 1 wherein the molar ratio of carbon oxide delivering agent to amine functional compound is between 0.8:1 and 20:1.

3. The process of claim 1 wherein in at least part of the ethanol-amine functional compound one or more OC.sub.2H.sub.4NH units are present as cyclic ethylene carbamate units or, if present, one or more NC.sub.2H.sub.4N units are present in the form of cyclic ethylene urea units.

4. The process of claim 1 wherein in at least part of the amine-functional compound one or more NC.sub.2H.sub.4N units are present in the form of cyclic ethylene urea units.

5. The process of claim 1 wherein the ethanolamine-functional compound is of the formula HO(C.sub.2H.sub.4NH).sub.qH wherein q is at least 1 and the amine-functional compound is of the formula NH.sub.2(C.sub.2H.sub.4NH).sub.rH wherein r is at least 1, wherein the sum of q+r is at least 3 and wherein optionally one or more OC.sub.2H.sub.4NH or NC.sub.2H.sub.4N units may be present as a cyclic ethylene urea or cyclic ethylene carbamate units.

6. The process of claim 1 wherein the ethanolamine-functional compound is AEEA (aminoethylethanolamine), CAEEA (the carbamate of aminoethylethanolamine), UAEEA (the urea of aminoethylethanolamine) or a mixture thereof and the amine-functional compound is EDA (ethylenediamine), EU (ethyleneurea) or a mixture thereof.

7. The process of claim 6 wherein the ratio of AEEA, UAEEA+CAEEA to EDA+EU is equal to or higher than 1.

8. The process of claim 1 wherein the ethanolamine-functional compound is MEA (monoethanolamine), CMEA (the carbamate of monoethanolamine) or a mixture thereof and the amine-functional compound is DETA (diethylenetriamine), UDETA (the urea of diethylenetriamine) or a mixture thereof.

9. The process of claim 8 wherein the ratio of MEA+CMEA to DETA+UDETA is higher than 1.

10. The process of claim 1 wherein the ethanolamine-functional compound is MEA (monoethanolamine), CMEA (the carbamate of monoethanolamine) or a mixture thereof and the amine-functional compound is EDA (ethylenediamine), EU (ethyleneurea) or a mixture thereof.

11. The process of claim 10 wherein the ratio of MEA+CMEA to EDA+EU is higher than 2.

12. The process of claim 9 wherein the ratio of MEA+CMEA to DETA+UDETA is higher than 2.

13. The process of claim 11 wherein the ratio of MEA+CMEA to EDA+EU is higher than 3.

Description

EXAMPLES

Example 1 Reaction of AEEA with EDA and EU CO/Amine=1:1

(1) 1 mole of AEEA was reacted with 1 mole of urea in an autoclave at 170 C. for 0.5 h. The following GC analysis showed that 93% of AEEA had been converted to UAEEA. After venting the autoclave 1.2 mole of EDA and 0.2 mole of urea were added and the temperature was then increased to 280 C. and kept constant for 5 h. GC-analysis of the reaction mixture indicated 2.1% of L-TETA and 27.5% of UTETA (i.e. the sum of the three different UTETAs).

(2) After cooling to room temperature 4.17 g of the reaction mixture were removed and hydrolysed with 4.11 g NaOH in 20 mL of water, at 200 C. for 1 h. Subsequent analysis by gas chromatography using a flame ionization detector (GC-FID analysis) (water not included) of the liquid phases showed the formation of 32.2% L-TETA and 5.5% UTETAs.

Comparative Example 2 Reaction of AEEA with EDA and EU CO/Amine=1:1.8

(3) 3 moles of EDA, 1 mole of AEEA and 1.65 moles of urea were reacted at 280 C. for 2 h in a closed pressure vessel. GC-analysis of the reaction mixture indicated 2.9% of L-TETA and 11.6% of UTETA (i.e. the sum of the three different UTETAs). After cooling to room temperature the mixture was then hydrolysed using 4 g of NaOH and 20 g of water at 200 C. for 1 h. GC-FID analysis (water not included) showed the liquid phases to contain 9.1% L-TETA and 2% UTETAs.

Comparative Example 3 Reaction of AEEA with EDA and EU CO/Amine=1:3

(4) 1 mole of AEEA, 1 mole of EU and 2 moles of EDA were reacted at 300 C. for 6 h in a closed pressure vessel. GC-analysis of the reaction mixture indicated 2.4% of L-TETA and 18.8% of UTETA (i.e. the sum of the three different UTETAs).

(5) After cooling to room temperature the mixture was then hydrolyzed using 4 g of NaOH and 20 g of water, at 200 C. for 1.5 h. GC-FID analysis (water not included) showed the formation of 15.3% L-TETA and 2.1% UTETAs.

Example 4 Reaction of AEEA with EDA and EU CO/Amine=2.1:1

(6) 1 mole of AEEA and 1.1 mole of urea were reacted at 170 C. for 1.5 h in a closed pressure vessel. The reaction vessel was then allowed to cool to room temperature, at which point the lid was removed and 1 mole of EU was added. The resealed vessel was then heated to 280 C. and held at that temperature for 5 h.

(7) For the hydrolysis 4 g of the reaction mixture was reacted with 4 g of NaOH in 20 g of water, at 200 C. for 1 h.

(8) GC-FID analysis (water not included) showed the liquid phases to contain 22.4% of L-TETA and 27.5% UTETAs, or in total 49.9 wt % of L-TETA including urea precursors thereof.

Example 5 Reaction of UAEEA with EDA and EU CO/Amine=1.35:1

(9) 1 mole of UAEEA, 1.7 mole of EU, and 0.3 mole of EDA were reacted at 270 C. for 5 h in a closed pressure vessel. GC-FID analysis showed 40.7% of urea precursors of L-TETA (UTETAs). The sample was not hydrolyzed.

Example 6 Reaction of DETA with CMEA at Different Molar Ratios

(10) DETA was reacted with molar equivalents of CMEA ranging from 0.5 to 2.0 at 275 C. for 4 hrs in a closed pressure vessel. CMEA takes the dual role of ethanolamine and CO source and the ratios CO/amine and ethanolamine/amine is equal to the CMEA/DETA ratio. The weight fractions of the main components were determined by GC-FID analysis of the product mixture and clearly show that the yield of higher ethylene amines including their CO containing derivatives increases with the CMEA/DETA ratio. The tetraamines (TETA) dominate at all ratios. At higher ratios the relative amounts of pentaamines and higher (TEPA) increase as expected assuming a consecutive reaction between CMEA and the TETA initially formed.

(11) TABLE-US-00001 Moles CMEA/DETA (carbon oxide delivering agent/amine agent) Examples: in reactants 0.5 0.8 1.0 1.2 1.5 2.0 Reaction mixture after 4 hrs in wt %: MEA 12.0 7.7 5.0 2.7 1.2 0.0 DETA 35.2 15.4 10.2 6.5 2.9 1.3 UDETA 40.0 40.0 41.9 39.7 32.1 28.2 MEA + DETA + UDETA 87.3 63.1 57.1 48.8 36.2 29.5 TETA 8.8 24.5 24.1 26.8 34.2 35.0 TEPA 0.6 3.9 8.6 11.5 17.9 24.3 TETA 9.4 28.5 32.7 38.3 52.1 59.3