Process for manufacturing hydroxyethyl ethylene amines

Abstract

A process for preparing hydroxyethyl ethylene amines and/or ethylene urea derivatives thereof includes reacting monoethylene glycol with an amine-functional compound having at least two —NH— units, of which at least one is selected from the group of primary amine groups and cyclic secondary amine groups, in the presence of a carbon oxide-delivering agent. The amine-functional compound includes at least one —NH—CH2-CH2-NH— unit, wherein one or more —NH—CH2-CH2-NH— units in the amine-functional compound may be present in the form of piperazine moieties or ethylene urea moieties. The molar ratio of amine-functional compound to monoethylene glycol is in the range of 0.2:1 to 1.5:1 and the molar ratio of carbon oxide-delivering agent to —NH—CH2-CH2-NH— units in the amine-functional compound is at least 0.5:1. The process allows the conversion of monoethylene glycol into ethanol amines in the absence of metals-containing catalysts and without using ammonia.

Claims

1. Process for preparing hydroxyethyl ethylene amines and/or ethylene urea derivatives thereof comprising the step of reacting monoethylene glycol with an amine-functional compound comprising at least two —NH— units of which at least one is selected from the group of primary amine groups and cyclic secondary amine groups, the amine-functional compound comprising at least one —NH—CH2-CH2-NH— unit, wherein one or more —NH-CH2-CH2-NH— units in the amine-functional compound may be present in the form of piperazine moieties of the formula ##STR00008## or ethylene urea moieties of the formula ##STR00009## in the presence of a carbon oxide-delivering agent, wherein the molar ratio of amine-functional compound to monoethylene glycol is in the range of 0.2:1 to 1.5:1, wherein the molar ratio of carbon oxide-delivering agent to —NH-CH2-CH2-NH— units in the amine-functional compound is at least 0.5:1, wherein a —NH-CH2-CH2-NH— unit is a unit which can form an ethylene urea unit in the amine-functional compound, and wherein the carbon oxide delivering agent is selected from the group of carbon dioxide, the CO adduct of monoethylene glycol selected from the group of cyclic ethylene carbonate and HO-CH2-CH2-O—C(O)—O-CH2-CH2-OH, and urea-derivatives of ethylene amine compounds.

2. Process according to claim 1, wherein the carbon oxide-delivering agent is selected from the group of carbon dioxide and ethylene urea (EU) of the formula ##STR00010##

3. Process according to claim 1, wherein the molar ratio of amine-functional compound to monoethylene glycol is at least 0.5:1.

4. Process according to claim 1, wherein the molar ratio of carbon oxide-delivering agent to —NH-CH2-CH2-NH— units in the amine-functional compound is at least 0.7:1.

5. Process according to claim 4, wherein the molar ratio of carbon oxide-delivering agent to —NH-CH2-CH2-NH— units in the amine-functional compound is between 0.7:1 and 3:1.

6. Process according to claim 1, wherein at least 50% of CO added in the process is added in the form of a CO adduct of monoethylene glycol selected from the group of cyclic ethylene carbonate and HO-CH2-CH2-O—C(O)—O-CH2-CH2-OH, or in the form of urea-derivatives of ethylene amine compounds.

7. Process according to claim 1, wherein the reaction product comprises alkanolamines of the formula NH2-(CH2-CH2-NH)q-CH2-CH2-OH, wherein q has a value of 1-10, wherein one or more —NH-CH2-CH2-NH— units may be present as cyclic ethylene urea units or piperazine units, and/or linear ethylene urea units and wherein one or more —NH-CH2-CH2-OH units may be present as cyclic ethylene carbamate units, and wherein one or more alkanol amines or derivatives thereof can be connected to each other via a linear ethylene urea structure.

8. Process according to claim 1, wherein the amine-functional compound comprises ethylene diamine (EDA), ethylene urea (EU), or a mixture thereof, and the reaction product comprises aminoethyl ethanolamine (AEEA) and/or urea and carbamate derivatives thereof.

9. Process according to claim 1, wherein the molar ratio of amine-functional compound to monoethylene glycol is at least 0.8:1 and at most 1.2:1.

10. Process according to claim 1, wherein the molar ratio of carbon oxide-delivering agent to —NH-CH2-CH2-NH— units in the amine-functional compound is at least 1:1 and at most 3:1.

11. Process according to claim 10, wherein the molar ratio of carbon oxide-delivering agent to —NH-CH2-CH2-NH— units in the amine-functional compound is between 1:1 and 1.75:1.

12. Process according to claim 1, wherein essentially all of CO added in the process is added in the form of a CO adduct of monoethylene glycol selected from the group of cyclic ethylene carbonate and HO-CH2-CH2-O—C(O)—O-CH2-CH2-OH, or in the form of urea-derivatives of ethylene amine compounds.

13. Process according to claim 1, wherein the reaction product comprises alkanolamines of the formula NH2-(CH2-CH2-NH)q-CH2-CH2-OH, wherein q has a value of 1 or 2, wherein one or more —NH-CH2-CH2-NH— units may be present as cyclic ethylene urea units or piperazine units, and/or linear ethylene urea units and wherein one or more —NH-CH2-CH2-OH units may be present as cyclic ethylene carbamate units, and wherein one or more alkanol amines or derivatives thereof can be connected to each other via a linear ethylene urea structure.

14. Process according to claim 1, wherein the reaction product comprises alkanolamines of the formula NH2-(CH2-CH2-NH)q-CH2-CH2-OH, wherein q has a value of 1-10, wherein one or more —NH-CH2-CH2-NH— units may be present as linear ethylene urea units of the formula ##STR00011##

15. Process according to claim 1, wherein the reaction product comprises alkanolamines of the formula NH2-(CH2-CH2-NH)q-CH2-CH2-OH, wherein q has a value of 1-10, wherein one or more —NH-CH2-CH2-OH units may be present as cyclic ethylene carbamate units of the formula ##STR00012##

Description

EXAMPLE 1: MEG+EDA+EU AT DIFFERENT CO:AMINE-FUNCTIONAL COMPOUND MOLAR RATIOS

(1) Reaction mixtures were prepared comprising monoethylene glycol, ethylene diamine, and ethylene urea. The molar ratio between amine-functional compound (the total of ethylene diamine and ethylene urea) and monoethylene glycol was 1:1. The amount of ethylene urea was selected such that the molar ratio of CO to amine-functional compounds (EDA+EU) was at the value specified in the table, varying between 0.05:1 and 1.5:1. At ratios above 1:1 CO2 is provided to the reaction mixture.

(2) The reaction mixtures were brought to a temperature of 270° C. under autogenous pressure, and allowed to react for 5 hours. After the reaction, the reaction mixtures comprised the following amount of (U)AEEA compounds, calculated in mole percentage based on the starting amount of MEG in moles.

(3) TABLE-US-00001 Experiment 1.1 1.2 1.3 1.4 1.5 1.6 1.7 CO:(EDA + EU) 0.05 0.3 0.7 0.9 1.0 1.25 1.5 molar ratio Σ(U)AEEA 0.0 5.1% 10.8% 13.0% 19.6% 20.2% 14.2%

(4) As can be seen from this data, a CO:(EDA+EU) ratio of 0.05:1 or 0.3:1 is insufficient to obtain a meaningful conversion to AEEA. At high CO:amine ratios (above 1.25:1), the yield of AEEA decreases.