Method for producing alkyleneamine compounds

Abstract

The present invention provides a method for producing an alkyleneamine compound, comprising the steps of: In a reaction medium, at least one primary amine group, or at least one cyclic secondary amine group, or at least one primary amine group and at least one cyclic secondary amine group, and a compound represented by formula I [Formula 1] TIFF2022519722000016.tif5859 wherein A is selected from the group of C2-C4 alkylene units optionally substituted with one or more C1-C3 alkyl groups. reacting an alkylene urea compound containing at least one cyclic alkylene urea group of formula I with an alkyl halide compound to form an alkylene amine hydrohalide salt containing at least one cyclic alkylene urea group of formula I, wherein the alkyl halide compound is selected from the group consisting of haloalkanes having 2 to 6 halogen atoms and haloaminoalkanes; reacting an alkyleneamine hydrohalide salt with a base to form an alkyleneamine compound comprising at least one cyclic alkyleneurea group of formula I. In one embodiment, the reaction is carried out in the presence of one or more ammonia and additional alkyleneamine compounds. The process according to the present invention produces fewer cyclic and branched chain by-products and more linear higher alkylene amines, particularly linear ethylene amines selected from L-TETA, L-TEPA and L-PEHA, than conventional processes.

Description

[Technical field]

[0001] The present invention relates to a method for the preparation of alkyleneamine compounds. As will be discussed in more detail below, within the scope of this application, the term alkyleneamine compounds includes polyalkylenepolyamines, as well as their urea and alkyl derivatives. [Background technology]

[0002] Ethyleneamines, especially the higher ethyleneamines such as triethylenetetramine (TETA), tetraethylenepentamine (TEPA) and pentaethylenehexamine (PEHA), are attractive products from a commercial standpoint.

[0003] Currently, the primary route for the production of higher polyethyleneamines, i.e., ethyleneamines containing three or more ethylene units, is by reaction of 1,2-dichloroethane, also designated ethylene dichloride or EDC, with aqueous ammonia and / or one or more ethyleneamines. Ethyleneamine hydrochloride is formed in a displacement reaction, which is then neutralized by reaction with caustic to produce ethyleneamines and NaCl. This method is often designated the EDC route. The EDC route results in a mixture of many types of ethyleneamines, including linear ethyleneamines, branched ethyleneamines, and piperazine-containing ethyleneamines. Linear compounds include, for example, ethylenediamine (EDA), diethylenetriamine (DETA), linear triethylenetetramine (L-TETA), and higher ethyleneamines such as linear tetraethylenepentamine (L-TEPA). Piperazine-containing compounds are piperazine (PIP), N-aminoethylpiperazine (AEP), and N,N'-diaminoethylpiperazine. Branched chain compounds such as tris-aminoethylamine (TAEA) are also formed.

[0004] There is a need in the art for efficient methods of producing higher ethyleneamines, and alkyleneamine compounds in general, that provide the desired compounds in high yield and / or selectivity through an efficient process. In particular, there is a need in the art for methods that produce fewer cyclic and branched by-products and more linear higher alkyleneamine compounds, particularly linear higher alkyleneamine compounds that can be converted to linear ethyleneamines selected from L-TETA, L-TEPA, and L-PEHA. Summary of the Invention

[0005] The present invention relates to a method for producing an alkyleneamine compound, comprising the steps of: in a reaction medium, at least one primary amine group, or at least one cyclic secondary amine group, or at least one primary amine group and at least one cyclic secondary amine group, and at least one amine group of formula I

[0006] [ka]

[0007] wherein A is selected from the group of C2-C4 alkylene units optionally substituted with one or more C1-C3 alkyl groups. An alkylene urea compound containing a cyclic alkylene urea group represented by the formula: with an alkyl halide compound to form an alkyleneamine hydrohalide salt containing at least one cyclic alkyleneurea group of formula I, wherein the alkyl halide compound is selected from the group consisting of haloalkanes having 2 to 6 halogen atoms, and haloaminoalkanes; - reacting an alkyleneamine hydrohalide salt with a base to form an alkyleneamine compound comprising at least one cyclic alkyleneurea group of formula I; The present invention relates to a method comprising the steps of:

[0008] Particularly when part of another formula, the structure of Formula I may also be represented in this application as -N(A)(CO)N-.

[0009] The process according to the invention allows higher alkyleneamine compounds to be produced in an efficient and selective manner with reduced amounts of piperazine-containing and branched by-products. The alkyleneamine compounds containing at least one cyclic alkyleneurea group can be converted to alkyleneamines by removing CO. As such, they are also used in industrial applications. Further advantages of the present invention and its specific embodiments will become apparent from the following application.

[0010] It is noted that DE-A-3214909 describes quaternary ammonium compounds suitable for use as additives for improving the adhesion of dyes to textiles, in particular the wet fastness of dyes. The quaternary ammonium compounds contain a cyclic alkylene urea structure. They can be prepared by reacting the tertiary amine group of an alkylene amine containing a tertiary amine group and a cyclic alkylene urea structure with 1,2-dichloroethane. This reference does not disclose the preparation of polyalkylene amine compounds according to the invention.

[0011] USSR Patent No. 176303 describes a process for the reaction of 1,2-dichloroethane with urea followed by hydrolysis of the resulting product to form ethylenediamine. This reference does not disclose the use of alkylene ureas.

[0012] The present invention will now be described. [Brief description of the drawings]

[0013] [Figure 1] FIG. 1 illustrates some reactions that may occur in one embodiment of the method according to the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] In the first step of the process according to the invention, an alkylene urea compound is reacted with an alkyl halide compound in a reaction medium.

[0015] The alkylene urea compound comprises at least one primary amine group, or at least one cyclic secondary amine group, or at least one primary amine group and at least one cyclic secondary amine group, and at least one amine represented by formula I

[0016] [ka]

[0017] wherein A is selected from the group of C2-C4 alkylene units optionally substituted with one or more C1-C3 alkyl groups. The cyclic alkylene urea group includes In the cyclic alkylene urea group, A is preferably a C2-C3 alkylene unit optionally substituted by one or two C1 alkyl groups. A is preferably selected from the group ethylene, propylene and isopropylene, in particular ethylene.

[0018] The alkylene urea compound has at least one cyclic secondary amine group, or at least one primary amine group, or both. The primary amine group or the cyclic secondary amine group is reacted with an alkyl halide compound. A cyclic secondary amine group in the context of this application is a group of the formula

[0019] [ka]

[0020] wherein A has the meaning explained above. is the basis.

[0021] In one embodiment, the alkylene urea compound has Formula II: Formula II: R2-[-XA-] q-N(A)(CO)N-[AX-] p -A-NH2 [In the formula, R2 is selected from H and C1-C6 alkyl groups optionally substituted with one or more groups selected from -OH and -NH2, in particular 0, 1 or 2 groups selected from -OH and -NH2; X, at each occurrence, is selected from -O-, -NR2-, a group of formula I, and a group of formula III:

[0022] [ka]

[0023] are independently selected from A has the meaning explained above, p is an integer ranging from 0 to 8; q is an integer ranging from 0 to 8. It is a compound of the formula:

[0024] The options given above for A are applicable here. It is particularly preferred that A is ethylene.

[0025] X is preferably selected from -NH-, a group of formula III, and a group of formula I. When it is desired to produce a straight chain alkylene amine, X is preferably selected from NH and a group of formula I.

[0026] R2 is preferably selected from H, ethyl, propyl and isopropyl, especially ethyl, optionally substituted by one or two groups selected from -OH and -NH2. R2 is particularly preferably ethyl or propyl, especially ethyl substituted at the second carbon atom with -NH2 (aminoethyl or aminoisopropyl), or in the case of propyl, at the third carbon atom.

[0027] Because reaction of larger molecules to form even larger molecules is not always the goal, it may be preferred that the sum of p and q be at most 8, and in some embodiments at most 4 or at most 2.

[0028] Examples of preferred compounds of formula II are the urea adduct of diethylenetriamine (U-DETA), the monourea adducts of triethylenetetramine (U1-TETA and U2-TETA) in which the urea group can be at the terminal ethylene moiety or at the central ethylene moiety, and the mono- and di-urea adducts of tetraethylenepentamine bearing primary amine groups (U1-TEPA, U2-TEPA, DU1,3-TEPA). These compounds are particularly attractive when it is desired to produce linear polyethyleneamines and their corresponding urea products.

[0029] Examples of other compounds which may be used in the process according to the invention are compounds consisting of an ethyleneamine chain provided with a urea group spanning the nitrogen atom on either side of a terminal ethylene moiety and an ethylene chain spanning the nitrogen atom on either side of the other ethylene moiety, e.g. U1P3-TEPA and U1P4-TEPA.

[0030] Generally, in this application, compounds are named as follows: The letter symbols refer to the longest linear ethyleneamine chain. U refers to the presence of a cyclic urea group resulting from the presence of a urea group spanning two adjacent nitrogen atoms connected via an ethylene moiety, ie, a group of formula I where A is an ethylene group. P refers to the presence of a piperazine moiety resulting from the presence of an ethylene moiety spanning two adjacent nitrogen atoms connected via an ethylene moiety, ie, a group of formula III where A is an ethylene group. The numbers after the U or P prefix refer to the corresponding nitrogen atom in the chain to distinguish between the different possible structures. The letter preceding the U or P prefix refers to the number of the group, with D representing di- or 2-groups and T representing tri- and tetra-, or 3- and 4-groups, respectively. When T is used, it is clear from the context whether tri- or tetra- is meant.

[0031] In another embodiment, the alkylene urea compound has formula IV Formula IV:R2-[-XA-] q -N(A)(CO)N-[AX-] p -AN(A)(A)HN wherein R2, X, A, q and p have the meanings given above. The options presented above are applicable here as well.

[0032] An example of a preferred compound of formula IV is the urea adduct of piperazinoethylethylenediamine (UP-TETA).

[0033] Mixtures of alkylene urea compounds may also be used.

[0034] In the process according to the invention, an alkylene urea compound is reacted with an alkyl halide compound, which is discussed below. The alkyl halide compound is selected from the group of haloalkanes having 2 to 6 halogen atoms, and haloaminoalkanes.

[0035] In one embodiment, the alkyl halide compound is a haloalkane having 2-6 halogen atoms, i.e. an alkane substituted with 2-6 halogen atoms. In one embodiment, the alkyl halide compound is a dihaloalkane, more specifically a C2-C10 alkane substituted with two halogen atoms, in particular two chlorine atoms. When a dihaloalkane is used, both halogen atoms of the molecule react with the alkylene urea compound, resulting in the formation of a longer molecule. As will be discussed in more detail below, this makes it an attractive method for producing higher alkylene amines. In the case of a dihaloalkane, it may be preferred that the halogen atoms are at opposite ends of the alkane chain, i.e. an alpha-omega dihaloalkane. The use of haloalkanes having more than two halogen atoms, for example up to 3, 4, ... 6, is also possible, but this results in the formation of a complex reaction mixture. In general, it is preferred that the haloalkane is a C2-C10 dihaloalkane, in particular a C2-C4 dihaloalkane. Particularly preferred compounds are 1,1-dichloroethane, 1,2-dichloroethane (often designated ethylene dichloride or EDC), 1,2-dichloropropane and 1,3-dichloropropane, with ethylene dichloride being especially preferred. 1,2,3-trichloropropane (TCP) may also be attractive.

[0036] In one embodiment, the alkyl halide compound is an amino alkyl halide, otherwise denoted as a haloaminoalkane. A haloaminoalkane is an alkane, in particular a C2-C10 alkane, substituted with one or more halogen atoms and one or more amino groups. The combination of one or more halogen atoms and one or more amino groups makes the compound interestingly dually reactive. In this embodiment, the haloaminoalkane may have one, two or more, i.e. up to six halogen substituents, in particular one or two, more particularly one. The haloaminoalkane may have one, two or more, i.e. up to six amino groups, in particular one or two, more particularly one. The alkane is preferably a C2-C4 alkane. Particularly preferred compounds are 1-chloro-2-amino-ethane, 1-chloro-3-aminopropane and 1-chloro-2-aminopropane, or their corresponding hydrochlorides.

[0037] The halogen in the alkyl halide compound can be selected from chlorine, bromine, and iodine. Compounds containing one or more halogens can also be used. Although the use of compounds containing bromine and iodine is technically possible, the use of compounds containing chlorine is generally preferred from the viewpoint of availability. In addition, chlorine-containing waste streams are easier to treat than bromine- or iodine-containing waste streams. Therefore, it is generally preferred that the alkyl halide compound is an alkyl chloride compound.

[0038] As will be apparent to one skilled in the art, combinations of different alkyl halide compounds may be used in the process of the present invention.

[0039] The reaction of the alkylene urea compound with the alkyl halide compound is generally carried out at a temperature in the range of 20 to 250° C., in particular in the range of 40 to 220° C. In one embodiment, the temperature is in the range of 40 to 150° C., in particular in the range of 80 to 120° C. In other embodiments, particularly when the reaction medium contains an additional amine compound, higher temperatures may be preferred, for example in the range of 100 to 220° C., in particular in the range of 120 to 200° C.

[0040] The reaction of the alkylene urea compound with the alkyl halide compound is generally carried out at a pressure ranging from atmospheric pressure to 150 bar, depending on the components present in the reaction medium and the reaction temperature. Generally, the pressure is applied to ensure that the reaction is carried out in the liquid phase at the specified temperature. In some embodiments, especially when the reaction is at a temperature below 120° C., the pressure generally ranges from 1 to 10 bar. In other embodiments, especially when the reaction is in the presence of ammonia, it may be desirable to use relatively high pressures, for example, in the range of 10 to 80 bar, especially 20 to 50 bar, as discussed below.

[0041] The reaction is carried out in a liquid reaction medium, i.e. in a reaction medium that is liquid under the reaction conditions. The reaction may be carried out in the presence of a solvent. Suitable solvents are compounds that allow solvation of the reactants without substantially interfering with the reaction. Water is a suitable solvent. Other suitable solvents include aromatic and aliphatic hydrocarbons, such as benzene and xylene, alcohols, such as methanol, ethanol, propanol, isopropanol, butanol, isobutanol, secondary butanol and tertiary butanol, esters, such as methyl acetate or ethyl acetate, and ethers, such as diisopropyl ether, diisobutyl ether, glycol dimethyl ether, diglycol dimethyl ether, dioxane and tetrahydrofuran (THF). A combination of solvents can also be used. It is within the scope of the skilled person to select the appropriate solvent.

[0042] The time required for the reaction depends on the desired degree of conversion, the nature and concentration of the reactants, and the reaction temperature. In general, the reaction time ranges from 5 minutes to 24 hours, more specifically from 10 minutes to 12 hours, and in some embodiments, from 0.5 to 8 hours.

[0043] The ratio between the various compounds depends on the number of halide substituents in the alkyl halide and the number of primary or cyclic secondary amine groups. In order to ensure that the amount of alkyl halide present during further processing is minimized, it is preferred that the ratio between the number of primary or cyclic secondary amine groups in the reaction medium and the number of halogen substituents in the alkyl halide is at least 1:1, in particular at least 1.05:1, more particularly at least 1.3:1. A value of up to 30:1 can be mentioned. The preferred ratio depends on the constituents in the reaction mixture. In one embodiment, generally, when the reaction mixture does not contain ammonia, the maximum value can be up to, in particular, 10:1, in particular 5:1. In an embodiment in which the reaction medium contains ammonia, a higher ratio is desirable, as will be discussed further, and can range, for example, from 10:1 to 30:1, in particular from 15:1 to 25:1.

[0044] The reaction product of the alkylene urea compound and the alkyl halide compound is the hydrogen halide salt of the alkylene amine or alkyl amine. The next step of the method according to the present invention is to neutralize the salt with a base to form the alkylene amine containing at least one cyclic alkylene urea group, with a halide salt as a by-product. The use of strong inorganic bases, such as NaOH and KOH, is generally preferred from an economical point of view, and this should be desirable since the resulting Na halide salt and K halide salt are relatively easily separated from the alkylene amine containing at least one cyclic alkylene urea group.

[0045] The amount of base can be calculated from the amount of the hydrogen halide salt of the alkyleneamine or alkylamine. Generally, the molar ratio of hydroxide ions derived from the base to the halide ions of the salt ranges from 1:1 to 10:1. The base can be provided in dissolved form, for example in the form of a solution in water. For an efficient process, water is preferably used as the solvent in the reaction of the alkyleneurea compound with the alkyl halide compound and as the solvent for the base. The neutralization of the alkyleneamine hydrogen halide salt is generally carried out at a temperature in the range of 0 to 200°C, in particular in the range of 10 to 150°C. The reaction pressure is not critical and can be, for example, in the range of atmospheric pressure to 15 bar, more particularly in the range of atmospheric pressure to 3 bar. Generally, the reaction time is from 1 minute to 24 hours, more particularly in the range of 10 minutes to 12 hours, in some embodiments in the range of 0.5 to 8 hours.

[0046] The product of this reaction is an alkyleneamine containing at least one cyclic alkyleneurea group, further designated U-alkyleneamine, along with a halide salt as a by-product. The U-alkyleneamine and the halide salt can be separated in various ways. For example, the U-alkyleneamine can be removed by evaporation. In another example, the halide salt can be removed by crystallization followed by phase separation. In a further example, the addition of an anti-solvent can result in the precipitation of the U-alkyleneamine while keeping the halide salt in solution, or vice versa, followed by removal of the precipitate. A combination of the various separation methods is also possible.

[0047] In one embodiment, the present invention allows selective preparation of high molecular weight polyalkylpolyamine compounds. In the alkylene urea used as starting material in the process according to the present invention, each C=O moiety blocks the nitrogen atom from reacting with the alkyl halide compound. This reduces the possibility of forming a wide range of polyalkylpolyamine products. For example, if the primary amine group is blocked by the C=O moiety, the molecule is prevented from forming a piperazine ring.

[0048] In one embodiment, the method according to the present invention comprises the steps of: Formula V R2-[-XA-]qN(A)(CO)N-[AX-]pA-NH-R1-NH-A-[XA]pN(A)(CO)N-[AX]q-R2 This results in the formation of a U-alkyleneamine compound.

[0049] In this formula, R2, X, A, p and q have the meanings given above. R1 is an alkylene chain resulting from an alkyl halide compound having 2 to 10 carbon atoms, in particular 2 to 4 carbon atoms. The compound of formula VI is obtained when the alkyl halide compound is a dihaloalkane of formula Y-R1-Y, where Y is selected from Cl, Br and I, Cl being the preferred halogen.

[0050] For example, the reaction of ethylene dichloride with U-DETA in a 1:2 molar ratio results in the formation of DU1,5-PEHA of the following formula:

[0051] [ka]

[0052] As illustrated in Example 1, this compound can be obtained with high selectivity in the process according to the invention.

[0053] In another example, the reaction of ethylene dichloride with U-DETA and piperazine results in the formation of U1-P4-TEPA of the following formula:

[0054] [ka]

[0055] A preferred embodiment of the process according to the present invention comprises reacting a urea adduct of diethylenetriamine with ethylene dichloride, resulting in the formation of the diurea adduct of pentaethylenehexamine.

[0056] In one embodiment, the method according to the present invention comprises reacting a compound of formula VI: Equation VI R2-[-XA-]qN(A)(CO)N-[AX-]pA-NH-R1-NH2 [wherein R1, R2, X, A, p and q have the meanings given above] This results in the formation of a U-alkyleneamine product of formula Y-R1-NH2, which can be obtained when the alkyl halide compound is a haloaminoalkane of formula Y-R1-NH2, where Y has the meaning given above. Below is illustrated the reaction of U-DETA with aminoethylene chloride to form U-TETA, and the reaction of U-TETA with aminoethylene chloride to form U-TEPA. There are two arrows indicating that the reaction involves two steps, namely the formation of the hydrochloride salt (not shown) and the neutralization reaction, both of which can of course be carried out in a single-step process.

[0057] [ka]

[0058] The U-alkyleneamine can be treated as desired. In one embodiment, the U-alkyleneamine is converted to the corresponding alkyleneamine under removal of CO2, which is carried out simultaneously with or after the step of reacting the alkyleneamine hydrochloride with a base. This process is sometimes referred to as the CO2 removal step and can be carried out in various ways.

[0059] In one embodiment, U-alkyleneamine is reacted with water in liquid phase to form the corresponding alkyleneamine under removal of CO2. The reaction with water is generally carried out at a temperature of at least 150°C. If the reaction temperature is below 150°C, U-alkyleneamine does not react to a significant extent. The reaction is preferably carried out at a temperature of at least 180°C, in particular at least 200°C, more particularly at least 230°C, even at least 250°C. Preferably, the temperature during this step does not exceed 400°C, in particular at most 350°C, more particularly at most 320°C.

[0060] The pressure in the process is not critical as long as the reaction medium is in the liquid phase. Typical ranges include values ​​between 0.5 and 100 bar, depending on the desired temperature. In order to maintain sufficient amounts of amine and water in the medium, it is preferred that the CO2 removal step is carried out at at least 5 bar, in particular at least 10 bar. In view of the high costs associated with high pressure equipment, it may be preferred that the pressure is at most 50 bar, in particular at most 40 bar.

[0061] The amount of water depends on the desired degree of conversion and the process conditions. In general, the amount of water is at least 0.1 mole of water per mole of urea moiety in the feedstock. Larger amounts are often used, for example at least 0.1 mole of water per mole of urea moiety, particularly at least 0.5 mole of water per mole of urea moiety. The maximum amount is not critical to the process according to the invention, but too much water will require unnecessarily large equipment. As a general maximum amount, an amount of water of up to 500 moles per mole of cyclic ethylene urea moiety can be mentioned, in particular up to 300 moles, more particularly up to 200 moles, and in some embodiments up to 100 moles or up to 50 moles.

[0062] It is preferred to carry out CO2 removal during the reaction, for example by venting the reaction vessel, preferably by providing a stripping gas, such as nitrogen or steam.

[0063] In one embodiment, the U-alkyleneamine is reacted in the liquid phase with water in an amount of 0.1 to 20 moles of water per mole of urea moiety at a temperature of at least 230° C. with removal of CO2. It has been found that the use of low amounts of water combined with relatively high temperatures and CO2 removal results in an efficient process with good conversion and low by-product formation.

[0064] In one embodiment, a U-alkyleneamine is reacted with an alkyleneamine from which a carbonyl moiety can be removed, resulting in the conversion of the U-alkyleneamine to its corresponding alkyleneamine and the simultaneous conversion of the alkyleneamine from which a carbonyl moiety can be removed to a U-alkyleneamine. This process can also be described as a carbonyl rearrangement reaction.

[0065] In a further embodiment, the U-alkyleneamine is reacted with a strong base, ie, a base having a pKb less than 1, to form the corresponding alkyleneamine and carbonate.

[0066] The use of strong inorganic bases is considered to be preferred. In one embodiment, the strong inorganic base is selected from the group of metal hydroxides, in particular from the group of alkali metal and alkaline earth metal hydroxides, in particular from sodium hydroxide, potassium hydroxide, lithium hydroxide, calcium hydroxide, magnesium hydroxide and barium hydroxide. In one embodiment, the strong inorganic base is selected from the group of metal oxides, in particular from the group of alkali metal and alkaline earth metal oxides, in particular from calcium oxide, magnesium oxide and barium oxide. It may be preferred to select strong inorganic bases from the group of sodium hydroxide, potassium hydroxide, magnesium (hydr)oxide and calcium (hydr)oxide. The use of sodium hydroxide and potassium hydroxide may be considered to be particularly preferred. Other strong inorganic bases may also be used, for example ammonium hydroxide. As will be clear to the skilled person, mixtures of various inorganic bases may be used. Compounds containing a base in addition to other constituents may also be used, so that the compound may be converted to an inorganic base in the reaction medium. The molar amount of base may be calculated relative to the molar amount of alkylene urea moiety to be converted. Values ​​of at least 0.2:1 may be mentioned. When it is desired to obtain complete conversion of the alkylene urea moiety to the corresponding alkylene amine compound, it may be preferable to use a larger amount, for example, a molar ratio of at least 1:1, particularly at least 1.5:1. It may be preferable to use a larger amount to increase the reaction rate, for example, a molar ratio of at least 2:1, particularly at least 2.5:1. Since a large amount of base does not contribute to further conversion and ultimately results in additional costs, it is preferable that the molar ratio of base to the molar amount of alkylene urea is at most 20:1, particularly at most 15:1, more particularly at most 10:1. It has been found that even smaller amounts of inorganic base may be sufficient. More particularly, it has been found that good results can be obtained with a molar ratio of base to alkylene urea moiety of at most 7.5:1, particularly at most 6.5:1, even more particularly at most 5.5:1. It has been found that the use of a molar ratio of at most 5.5:1 results in complete conversion of the alkylene urea moiety and a high yield of the obtained alkylene amine compound.It may be preferred to use less base per mole of alkylene urea moiety, for example in a molar ratio of up to 5:1, particularly up to 4:1, and more particularly up to 3:1.

[0067] The treatment with a base can be carried out, for example, by contacting the material to be treated with a concentrated aqueous solution of an inorganic base. Depending on the nature of the base and the further composition of the reaction mixture, it may also be possible to add the base in solid form and dissolve it in the reaction medium. As will be clear to those skilled in the art, the aim is to have the base in solution, so that the hydroxyl groups can react with the CO2 adduct, while at the same time avoiding unnecessary dilution of the reaction medium.

[0068] The reaction can be carried out at temperatures between room temperature and 400°C. The temperature and pressure should be selected so that the reaction mixture is in the liquid phase. High temperatures are advantageous as they result in a reduction in the reaction time. It may be preferred to carry out the reaction at a temperature of at least 100°C, in particular at least 140°C, in particular at least 170°C. On the other hand, high temperatures may result in the formation of unwanted by-products. It may therefore be preferred to carry out the reaction at a temperature of up to 350°C, in particular up to 280°C.

[0069] Depending on the reaction temperature, the reaction time may vary within a wide range, for example from 15 minutes to 24 hours. It may be preferable for the reaction time to vary between 1 hour and 12 hours, in particular between 1 hour and 6 hours. If a small amount of base is used, a longer reaction time may be necessary to obtain the desired degree of conversion.

[0070] Upon completion of the reaction, a reaction mixture is obtained containing the ethyleneamine compound and the carbonate salt of the inorganic base, which may be removed by methods known in the art, such as by filtration if the salt is in solid form, or more commonly by phase separation.

[0071] Combinations of various CO2 elimination steps are also possible, for example treatment with water with CO2 removal followed by treatment with a base, optionally with a step of intermediate product removal.

[0072] As discussed above, the method according to the present invention also includes a step of reacting the alkyleneamine hydrohalide salt with a base to form an alkyleneamine containing at least one cyclic alkyleneurea group. When it is intended to convert the alkyleneamine containing at least one cyclic alkyleneurea group to the corresponding alkyleneamine, it is possible to convert the alkyleneamine hydrohalide salt to the alkyleneamine in a single step by reacting it with an inorganic base. The conversion of U-alkyleneamine to the corresponding alkyleneamine requires more stringent conditions than the conversion of alkyleneamine hydrohalide salt to U-alkyleneamine. Therefore, when the two reactions are combined in a single step, the conditions and the amount of base should be selected so that both reactions are carried out. The conditions described above for the conversion of U-alkyleneamine to the corresponding alkyleneamine should be sufficient.

[0073] An interesting embodiment of the process according to the invention is the use of the presence of an alkylene urea compound to change the product distribution in a process in which an alkylene dichloride is reacted with one or more of ammonia or additional alkylene amine compounds to form an alkylene amine, e.g., in the conventional process for producing ethylene amines from EDC and ammonia (typically aqueous ammonia).

[0074] In this case, the reaction medium comprises an alkylene urea compound, an alkyl halide compound selected from a polyhaloalkane or an aminohaloalkane, and one or more of ammonia and an additional alkylene amine compound, the additional alkylene amine compound being represented by the formula H 2 N-[AX-] x -A-NH 2 (wherein x is an integer ranging from 0 to 8), an alkyleneamine of the formula Y-[AX-] x -A-NH2 where Y is a piperazine ring and x is an integer ranging from 0 to 8, and piperazine. When present, the additional alkyleneamine compound is selected from the group of compounds of formula H 2 N-[CH2-CH2-NH-] x -CH2-CH2-NH 2 (wherein x is an integer ranging from 0 to 8), ethyleneamines of the formula Y-[CH2-CH2-NH-] x -CH2-CH2-NH 2 In some cases it may be preferred to select from the group of compounds of the formula: (wherein Y is a piperazine ring and x is an integer ranging from 0 to 8), and piperazines, in particular from ethylenediamine, diethylenetriamine, triethylenetetramine and piperazine. Of course, combinations of different additional alkyleneamine compounds can also be used.

[0075] The alkyl halide compound is reacted with ammonia or additional alkyleneamine compounds to form alkylamine hydrohalide salts. The alkyl halide is also reacted with one or two alkyleneurea compounds to form alkyleneamine hydrohalide salts containing at least one cyclic alkyleneurea group. Figure 1 illustrates some of the reactions that may occur when a urea derivative of diethylenetriamine is reacted with ethylene dichloride in the presence of ammonia, ethylenediamine, or PIP, and the resulting hydrochloride salts.

[0076] The composition containing various alkylamine hydrohalide compounds is reacted with base to convert the salts into the corresponding amine products. Depending on the amount of base and conversion conditions, the resulting product is a mixture containing alkyleneamines and optionally U-alkyleneamines. If U-alkyleneamines are present, they can be converted into alkyleneamines by the methods presented above.

[0077] In this embodiment, when the alkylene dichloride is reacted with one or more of ammonia or additional alkylene amines in the presence of an alkylene urea, the ratio between the various compounds depends on the number of halide substituents in the alkyl halide and the total number of primary amine groups, cyclic secondary amine groups, and ammonia. In order to ensure that the amount of alkyl halide present during further processing is minimized, it is preferred that the ratio of the total number of primary amine groups, cyclic secondary amine groups, and ammonia in the reaction medium to the number of halogen substituents in the alkyl halide is at least 1.05:1, in particular at least 1.1:1. At the most, a value of 30:1 can be mentioned. In particular, when the system contains ammonia, a relatively high ratio, for example at least 5:1, can be preferred. In this embodiment, a range of 10:1 to 30:1 is preferred, in particular 15:1 to 25:1 can be used.

[0078] In this embodiment, when the alkylene dichloride is reacted with one or more of ammonia or additional alkylene amines in the presence of an alkylene urea, it may be preferred to operate at relatively high temperatures, for example in the range of 100 to 220° C., in particular in the range of 120 to 200° C. In this embodiment, especially when ammonia is used as a reactant, it may be preferred to operate at relatively high pressures, for example in the range of 10 to 80 bar, in particular in the range of 20 to 50 bar. The general ranges given above for the process according to the invention apply here too.

[0079] The state of the product obtained is determined on the one hand by the relative amount of alkylene urea compound, and on the other hand by the total amount of ammonia and additional alkylene amine compound.For a meaningful change in the state of the product compared to the process carried out in the absence of alkylene urea compound, it is generally preferred that the ratio of the total of primary amine groups and cyclic secondary amine groups derived from alkylene urea compound to the total of primary amine groups and cyclic secondary amine groups derived from ammonia and additional alkylene amine compound is at least 0.1:1, in particular at least 0.2:1. The maximum number is generally at most 20:1, in particular at most 10:1. If this value is exceeded, the amount of ammonia and additional alkylene amine compound may be too small, and their influence on the state of the product may be insufficient to justify the effort. It is within the skill of the person skilled in the art to determine the appropriate ratio between different starting materials.

[0080] An example of a process according to this embodiment of the invention in which an alkylene dichloride is reacted with one or more of ammonia or additional alkylene amine compounds and an alkylene urea compound is as follows: reacting U-DETA with ethylene dichloride and ammonia to form U1-TETA; reaction of U-DETA with ethylene dichloride and ethylenediamine to form U1-TEPA; Reaction of U-DETA with ethylene dichloride and piperazine to form U1P4-TEPA.

[0081] As will be apparent to one skilled in the art, the product formed by this reaction can also be reacted with ethylene dichloride, or ammonia or an ethyleneamine compound or piperazine can be reacted with ethylene dichloride, resulting in the formation of a reaction mixture containing various components. The presence of an alkylene urea compound in the reaction mixture results in the formation of more linear ethyleneamine compound and less additional piperazine moieties than would be obtained if the alkylene urea moieties were not present.

[0082] The reaction mixture can be treated as desired. When ammonia is used, it may be attractive to recover an ammonia-containing gas stream from the product and reuse it in the process. When the reaction mixture contains cyclic ethylene urea compounds, the entire reaction mixture can be subjected to conditions such that the ethylene urea moieties are converted into ethylene amine moieties. However, it is also possible to subject the reaction mixture to a separation step to obtain a fraction with a reduced content of cyclic ethylene urea compounds and a fraction with an increased content of cyclic ethylene urea compounds, and to subject the latter fraction to conditions such that the ethylene urea moieties are converted into ethylene amine moieties. In general, the products of the reaction can be separated as desired by methods known in the art, for example by distillation, and the various fractions can be treated as desired, for example isolated as products or reused as starting materials.

[0083] The starting material of the method according to the invention is an alkylene urea compound that contains at least one primary amine group, at least one cyclic secondary amine group, or at least one primary amine group and at least one cyclic secondary amine group, and at least one cyclic alkylene urea group of formula I. This type of compound can be obtained by reacting an alkylene amine compound with a linear -NH-A-NH- moiety with a carbonyl delivery agent at a suitable reaction temperature. Suitable carbonyl delivery agents are compounds that contain a carbonyl moiety that can be rearranged to a -HN-A-NH- moiety. Examples include carbon dioxide and organic compounds whose carbonyl moiety is available for the above-described rearrangement. Organic compounds whose carbonyl moiety is available for rearrangement include urea and its derivatives, linear and cyclic alkylene ureas, especially cyclic alkylene ureas, mono- or di-substituted alkylene ureas, alkyl and dialkyl ureas, linear and cyclic carbamates, organic carbonates and their derivatives or precursors. Such derivatives or precursors may include, for example, ionic compounds, such as organic carbonates or bicarbonates, carbamic acids and related salts.Preferably, the carbonyl delivery agent is CO2, or an organic compound suitable for use as a carbonyl delivery agent and in which the alkylene is ethylene, or an ethylene urea compound or ethylene carbonate, and more preferably, the carbonyl delivery agent is added at least partially as carbon dioxide or as an ethylene urea compound, i.e., as a compound containing a group of formula I.The urea compound may be prepared by combining an alkylene amine compound having a linear -NH-A-NH- moiety with a carbon oxide delivery agent and heating the mixture to a temperature at which reaction occurs. The reaction is known and need not be described further here. Depending on the choice of carbonyl delivery agent and reaction conditions, it may also be possible to combine the formation of the urea compound with a reaction with an alkyl halide.However, considering that a carbonyl moiety compound is often used to block amine groups, it is generally preferred to first prepare an alkylene urea compound and then react the alkylene urea compound with an alkyl halide compound.

[0084] The process according to the invention and its various steps can be carried out in batch, fed-batch or continuous operation, for example in a cascade of continuous-flow reactors. Depending on the scale of operation, continuous operation may be preferred.

[0085] In the various structural formulas used herein, all options for A, R2 and X are independent unless specifically indicated otherwise. Preferably, all alkylene groups are ethylene groups.

[0086] As will be apparent to a person skilled in the art, the various embodiments of the invention can be combined unless they are mutually exclusive.

[0087] The present invention is illustrated by, but is not limited by, the following examples.

[0088] [Example 1]: Reaction of EDC with U-DETA 2.5 g (25 mmol) of EDC was slowly added to a mixture of 6.9 g (53 mmol) of U-DETA and 5 mL of distilled water at 50° C. After the addition of EDC was complete, the reaction mixture was heated at 105° C. for 4 hours to react U-DETA with EDC to form the hydrochloride salt of DU1,5-PEHA according to the following reaction:

[0089] [ka]

[0090] To convert the dihydrochloride salt of DU1,5-PEHA to DU1,5-PEHA, the reaction mixture was cooled to 50° C., at which point 4.2 mL (80 mmol) of 50 wt % aqueous NaOH was added. The mixture was then held at 50° C. for an additional 30 minutes. Water was then removed by evaporation under reduced pressure. 50 mL of ethanol was added, and the mixture was stirred for 5 minutes. The precipitate thus formed was removed by filtration and dried under reduced pressure to obtain approximately 9 g of a yellowish viscous material containing DU1,5-PEHA. The reaction scheme is presented below.

[0091] [ka]

[0092] To convert DU1,5-PEHA to L-PEHA, 4 g of the yellowish viscous material containing DU1,5-PEHA, 3.2 g (80 mmol) of NaOH, and 15 mL of distilled water were added to a 45 mL autoclave. The vessel was purged with N2(g) and then heated to 220° C. over 40 minutes and 2.5 hours at 220° C. After cooling to room temperature, a sample was removed and analyzed by gas chromatography coupled to a flame ionization detector (GC-FID) using an internal standard. According to the GC-FID analysis, the sample contained 53% DETA, 33% L-PEHA, and 12% (U)-PEHA. No trace of piperazine-containing or branched (U)-PEHA isomers was found. The high selectivity and yield for L-PEHA without significant amounts of higher molecular weight alkyleneamine congeners is very attractive from a commercial standpoint. The reaction scheme is presented below.

[0093] [ka]

[0094] [Example 2]: Reaction of EDC with U-DETA and ammonia A mixture of U-DETA (4.70 g, 36.4 mmol), EDC (3.60 g, 36.4 mmol) and aqueous ammonia (17.7 g, 35%, 364 mmol) was heated in a pressure autoclave at 100° C. for 4 h. The mixture was cooled, NaOH (2.91 g, 7.28 mmol) was added and the resulting mixture was analyzed by GC-FID to give a GC yield of U1-TETA of 10%. Higher yields can be obtained by optimization of the reaction.

[0095] [Example 3]: Reaction of EDC, U-DETA and piperazine A mixture of U-DETA (20.4 g, 0.16 mol), piperazine (13.6 g, 0.16 mol) and water (6.4 g) was heated to 65° C. in a round-bottom flask equipped with an internal thermometer, reflux condenser and dropping funnel. EDC (6.3 g, 0.06 mol) was added slowly via the dropping funnel. After 20 min (at the end of the exothermic reaction), 50 wt % aqueous NaOH (5.4 g, 0.13 mol) was added and the mixture was stirred at 65° C. for 15 min and analyzed by GC-MS and GC-FID. The reaction is shown below.

[0096] [ka]

[0097] The reaction yielded 6% U1P4-TEPA, 18% DP-TETA, and 6% TP-PEHA (GC area %), but significant amounts of piperazine and U-DETA remained because they were used in molar excess relative to the EDC dosage. Higher boiling point components, such as DU1,5-PEHA, and more U compounds may be present but cannot be detected with the GC-FID and GC-MS setup currently used.

[0098] [Example 4]: Reaction of DETA (for comparison) and U-DETA (invention) with EDC To investigate the effect of the cyclic urea group on the selectivity for reaction with EDC, experiments were carried out using either DETA (Comparative Examples A and B) or U-DETA (Inventive Example 4.1) as starting materials.

[0099] DETA or U-DETA was reacted with EDC (5M in water) at 100° C. for 30 minutes. The reaction mixture was then treated with 50 wt % aqueous NaOH solution (2.1 equivalents relative to EDC). After removing salts and water, the product mixture was analyzed by GC-MS and GC-FID. The GC-FID results are presented in the table below in wt %.

[0100] [Table 1]

[0101] As can be seen from the table, the reaction of U-DETA with EDC results in a much higher yield of L-PEHA product and only a small amount of AEP compared to the reaction of DETA with EDC. The present invention may include the following aspects. [1] A method for producing an alkyleneamine compound, comprising the steps of: in a reaction medium, at least one primary amine group, or at least one cyclic secondary amine group, or at least one primary amine group and at least one cyclic secondary amine group, and at least one amine group of formula I [ka] wherein A is selected from the group of C2-C4 alkylene units optionally substituted with one or more C1-C3 alkyl groups. An alkylene urea compound containing a cyclic alkylene urea group represented by the formula: with an alkyl halide compound to form an alkyleneamine hydrohalide salt containing at least one cyclic alkyleneurea group of formula I, wherein the alkyl halide compound is selected from the group consisting of haloalkanes having 2 to 6 halogen atoms, and haloaminoalkanes; - reacting the alkyleneamine hydrohalide salt with a base to form an alkyleneamine compound comprising at least one cyclic alkyleneurea group of formula I; A method comprising: [2] The method according to the above [1], wherein A is a C2-C3 alkylene unit optionally substituted by one or two C1 alkyl groups, preferably A is selected from the group of ethylene, propylene and isopropylene, in particular ethylene. [3] The alkylene urea compound used as a starting material is represented by the formula II Formula II: R2-[-XA-] q -N(A)(CO)N-[AX-] p -A-NH2 [In the formula, R2 is selected from H and C1-C6 alkyl groups optionally substituted with one or more groups selected from -OH and -NH2, in particular 0, 1 or 2 groups selected from -OH and -NH2; X, at each occurrence, is selected from -O-, -NR2-, a group of formula I, and a group of formula III: [ka] are independently selected from A has the meaning explained above, p is an integer ranging from 0 to 8; q is an integer ranging from 0 to 8. The method according to the above [1] or [2], wherein the compound is [4] The alkylene urea compound used as a starting material is represented by formula IV Formula IV:R2-[-XA-] q -N(A)(CO)N-[AX-] p -AN(A)(A)HN wherein R2, X, A, q and p have the meanings given above. The method according to any one of [1] to [3] above, wherein the compound is [5] The method according to any one of the above [1] to [4], wherein the alkyl halide compound is an alkyl chloride compound. [6] The method according to any one of the above [1] to [5], wherein the alkyl halide selected from the group of haloalkanes having 2 to 6 halogen atoms is selected from 1,2,3-trichloropropane or a C2 to C10 dihaloalkane, more particularly a C2 to C4 dihaloalkane, in particular 1,1-dichloroethane, 1,2-dichloroethane (often designated ethylene dichloride or EDC), 1,2-dichloropropane, or 1,3-dichloropropane, with ethylene dichloride being particularly preferred. [7] The method according to any one of the above [1] to [6], wherein the alkyl halide is selected from a haloaminoalkane, in particular a C2 to C10 alkane substituted with one or more halogen atoms and one or more amino groups, the haloaminoalkane preferably having one to six halogen substituents, in particular one or two, more particularly one, the haloaminoalkane preferably having one to six amino groups, in particular one or two, more particularly one, the alkane is preferably a C2 to C4 alkane, and 1-chloro-2-amino-ethane, 1-chloro-3-aminopropane and 1-chloro-2-aminopropane, or the corresponding hydrochlorides thereof, are particularly preferred. [8] The method, wherein the step of reacting the alkyleneamine hydrohalide salt with a base to form an alkyleneamine containing at least one cyclic alkyleneurea group is carried out using a strong inorganic base, in particular NaOH or KOH. [9] The cyclic alkylene urea product formed by the process of the present invention is a compound of formula V or a compound of formula VI Formula V R2-[-XA-]qN(A)(CO)N-[AX-]pA-NH-R1-NH-A-[XA]pN(A)(CO)N-[AX]q-R2 Equation VI R2-[-XA-]qN(A)(CO)N-[AX-]pA-NH-R1-NH2 wherein R2, X, A, p and q have the meanings given above and R1 is an alkylene chain resulting from said alkyl halide compound having 2 to 10 carbon atoms, in particular 2 to 4 carbon atoms. The method according to any one of the above [1] to [8],

[10] The method according to [1] above, wherein a urea adduct of diethylenetriamine is reacted with ethylene dichloride to result in the formation of a diurea adduct of pentaethylenehexamine.

[11] The method according to any one of the above [1] to

[10] , further comprising a CO2 elimination step, comprising converting the alkyleneamine containing at least one cyclic alkyleneurea group of formula I to the corresponding alkyleneamine under CO2 elimination, said step being carried out simultaneously with or after a step of reacting the alkyleneamine hydrochloride with an inorganic base.

[12] The reaction medium comprises one or more of an alkylene urea compound, an alkyl halide compound selected from a polyhaloalkane or an aminohaloalkane, and ammonia and an additional alkylene amine compound, the additional alkylene amine compound being represented by the formula H 2 N-[AX-] x -A-NH 2 (wherein x is an integer ranging from 0 to 8), an alkyleneamine of the formula Y-[AX-] x -A-NH 2 (wherein Y is a piperazine ring, and x is an integer ranging from 0 to 8), and piperazine.

[13] The alkyl halide compound is ethylene dichloride, and, if present, the additional alkylene amine compound is a compound represented by the formula H 2 N-[CH2-CH2-NH-] x -CH2-CH2-NH 2 (wherein x is an integer ranging from 0 to 8), ethyleneamines of the formula Y-[CH2-CH2-NH-] x -CH2-CH2-NH 2 (wherein Y is a piperazine ring and x is an integer ranging from 0 to 8), and from the group of piperazines, in particular ethylenediamine, diethylenetriamine, triethylenetetramine, and piperazine.

[14] The method according to any one of the above [1] to

[13] , comprising a step of producing an alkylene urea compound containing at least one primary amine group and at least one cyclic alkylene urea group of formula I by reacting an alkylene amine compound having a linear -NH-A-NH- group with a carbonyl donor.

Claims

1. A method for producing an alkyleneamine compound, comprising the steps of: in the reaction medium, at least one primary amine group and at least one compound of formula I 【Chemistry 1】 wherein A is selected from the group of C2-C4 alkylene units optionally substituted with one or more C1-C3 alkyl groups. an alkylene urea compound comprising at least one cyclic secondary amine group and at least one cyclic alkylene urea group of formula I, or an alkylene urea compound comprising at least one primary amine group, at least one cyclic secondary amine group, and at least one cyclic alkylene urea group of formula I, with an alkyl halide compound to form an alkyleneamine hydrohalide salt containing at least one cyclic alkyleneurea group of formula I, wherein the alkyl halide compound is selected from the group of haloalkanes having 2 to 6 halogen atoms, and haloaminoalkanes; - reacting said alkyleneamine hydrohalide salt with a base to form an alkyleneamine compound comprising at least one cyclic alkyleneurea group of formula I; A method comprising:

2. 2. The method of claim 1, wherein A is a C2-C3 alkylene unit optionally substituted with one or two C1 alkyl groups.

3. The alkylene urea compound used as the starting material is represented by the formula II Formula II: R2 - [-X-A-] ｑ -N(A)(CO)N - [A-X-] ｐ -A-NH2 [In the formula, R2 is selected from H and a C1-C6 alkyl group optionally substituted with one or more groups selected from -OH and -NH2; X, at each occurrence, is selected from -O-, -NR2-, a group of formula I, and a group of formula III: 【Chemistry 2】 are independently selected from A has the meaning explained above, p is an integer ranging from 0 to 8; and q is an integer ranging from 0 to 8. The method according to claim 1 or 2, wherein the compound is

4. The alkylene urea compound used as a starting material is represented by formula IV Formula IV: R2 - [-X - A -] ｑ -N(A)(CO)N - [A - X -] ｐ -A - N(A)(A)HN wherein R2, X, A, q and p have the meanings given above. The method according to any one of claims 1 to 3, wherein the compound is

5. The process according to any one of claims 1 to 4, wherein the alkyl halide compound is an alkyl chloride compound.

6. The process according to any one of claims 1 to 5, wherein the alkyl halide compound selected from the group of haloalkanes having 2 to 6 halogen atoms is 1,2,3-trichloropropane or a C2 to C10 dihaloalkane.

7. The method according to any one of claims 1 to 6, wherein the alkyl halide compound is a haloaminoalkane.

8. 8. The method of any one of claims 1 to 7, wherein the step of reacting the alkyleneamine hydrohalide salt with a base to form an alkyleneamine containing at least one cyclic alkyleneurea group of formula I is carried out using a strong inorganic base.

9. The alkyleneamine compound is a compound of formula V or a compound of formula VI Formula V R2-[-X-A-]q-N(A)(CO)N-[A-X-]p-A-NH-R1-NH-A-[X-A]p-N(A)(CO)N-[A-X]q-R2 Formula VI R2-[-X-A-]q-N(A)(CO)N-[A-X-]p-A-NH-R1-NH 2 wherein R2, X, A, p and q have the meanings given above, and R1 is an alkylene chain resulting from said alkyl halide compound having 2 to 10 carbon atoms. The method according to any one of claims 1 to 8, wherein

10. 2. The method of claim 1, wherein the urea adduct of diethylenetriamine is reacted with ethylene dichloride to result in the formation of the diurea adduct of pentaethylenehexamine.

11. 11. The method according to any one of claims 1 to 10, comprising a CO2 scavenging step, comprising converting the alkyleneamine compound containing at least one cyclic alkyleneurea group of formula I to the corresponding alkyleneamine under scavenging of CO2, said step being carried out simultaneously with or after the step of reacting the alkyleneamine hydrohalide salt with an inorganic base.

12. The reaction medium comprises an alkylene urea compound, an alkyl halide compound selected from a polyhaloalkane or an aminohaloalkane, and one or more of ammonia and an additional alkylene amine compound, the additional alkylene amine compound being represented by the formula H ２ N-[A-X-] ｘ -A-NH ２ wherein x is an integer ranging from 0 to 8; an alkyleneamine of the formula Y-[A-X-] ｘ -A-NH ２ 12. The method of any one of claims 1 to 11, wherein Y is a piperazine ring and x is an integer ranging from 0 to 8, and piperazine.

13. The alkyl halide compound is ethylene dichloride, and when present, the additional alkylene amine compound is of formula H ２ N-[CH 2-CH 2-NH-] ｘ -CH2-CH2-NH ２ ethyleneamines of the formula Y-[CH2-CH2-NH-], where x is an integer ranging from 0 to 8; ｘ -CH2-CH2-NH ２ 13. The method of claim 12, wherein the compound is selected from the group consisting of: wherein Y is a piperazine ring and x is an integer ranging from 0 to 8; and piperazine.

14. 14. The method of any one of claims 1 to 13, comprising the step of preparing an alkylene urea compound comprising at least one primary amine group and at least one cyclic alkylene urea group of formula I by reacting an alkylene amine compound having a linear -NH-A-NH- group with a carbonyl donor.

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