TW201509880A - Process for preparing N-alkylpiperazines - Google Patents

Abstract

A process for preparing an N-alkylpiperazine of formula I in which R1 is hydrogen (H), methyl, or ethyl, and R2 is C1 to C5 alkyl, by reacting an N-substituted diethanolamine of the formula II with ammonia or a primary amine of the formula H2N-R1 (III) in the presence of hydrogen and of a supported metallic catalyst, wherein the catalytically active composition of the catalyst prior to its reduction with hydrogen comprises from 20 to 85 wt% of oxygen-containing compounds of zirconium, calculated as ZrO2, from I to 30 wt% of oxygen-containing compounds of copper, calculated as CuO, from 14 to 70 wt% of oxygen-containing compounds of nickel, calculated as NiO, and from 0 to 5 wt% of oxygen-containing compounds of molybdenum, calculated as MoO3, and the reaction is carried out in the liquid phase at an absolute pressure in the range from 160 to 240 bar, at a temperature in the range from 180 to 230 DEG C, using ammonia or primary amine Ill in a molar ratio, with respect to diethanolamine II employed, of 5 to 50 and in the presence of 0.1 to 9.0 wt% of hydrogen, based on the total amount of diethanolamine II employed and ammonia or amine III.

Description

Method for preparing N-alkyl pipe

The present invention relates to a process for the preparation of the N-alkyl piperier of formula I Wherein R ¹ is hydrogen (H), methyl or ethyl, and R ² is C ₁ to C ₅ alkyl by the N-substituted diethanolamine of formula II

It is carried out by reacting with ammonia or a monoamine of the formula H ₂ NR ¹ (III) in the presence of hydrogen and a supported metal catalyst.

For example, the use of the product of the method includes as an intermediate in the preparation of an active pharmaceutical ingredient such as an antibiotic.

WO 03/051508 A1 (Huntsman Petrochemical) relates to a process for the amination of an alcohol using a specific Cu/Ni/Zr/Sn-containing catalyst, which in another embodiment contains Cr instead of Zr ( See page 4, lines 10-16). The catalyst described in this WO application does not contain alumina and does not contain cobalt.

WO 2008/006750 A1 (BASF AG) is a catalyst containing zirconium dioxide, copper, nickel and cobalt doped with special Pb, Bi, Sn, Sb and/or In, and is used for lending Use in a process for the preparation of an amine by reacting a primary or secondary alcohol, an aldehyde and/or a ketone with hydrogen and ammonia or a primary or secondary amine.

WO 2009/080507 A1 (BASF SE) is related to special Sn and Co doping Catalysts comprising zirconium dioxide, copper and nickel, and their use in a process for the preparation of an amine by reacting a primary or secondary alcohol, an aldehyde and/or a ketone with hydrogen and ammonia or a primary or secondary amine.

WO 2009/080506 A1 (BASF SE) is about special Pb, Bi, Sn, Mo, Sb and/or P-doped catalysts comprising zirconia, nickel and iron, and in relation to their use in the treatment of primary or secondary alcohols, aldehydes and/or ketones with hydrogen and ammonia or primary or secondary The use of a hydrazine reaction to produce an amine. The catalyst preferably does not contain Cu and does not contain Co.

WO 2009/080508 A1 (BASF SE) describes special Pb, Bi, Sn and/or Sb-doped catalysts comprising zirconia, copper, nickel, cobalt and iron, and their use in reacting primary or secondary alcohols, aldehydes and/or ketones with hydrogen and ammonia or primary or secondary amines Use in a process for the preparation of an amine.

WO 2011/067199 A1 (BASF SE) relates to certain alumina, copper, Catalysts of nickel, cobalt and tin and their use in processes for the preparation of amines from primary or secondary alcohols, aldehydes and/or ketones. On page 25, lines 21-22 generally refer to the preparation of N,N'-dimethylperazine from N-methyldiethanolamine and monomethylamine (MMA).

WO 2011/157710 A1 and WO 2012/049101 A1 (both BASF SE) Description of the preparation of certain cyclic tertiary methylamines wherein, in the presence of a copper-containing heterogeneous catalyst in the liquid phase at elevated temperatures, 1,4-aminobutanol, 1,5-aminopentanol, The amine alcohol and the aminoethylethanolamine of the group of aminodiglycol (ADG) are reacted with a defined primary or secondary alcohol.

CN 102 101 847 A(Zhangjiagang Tianyou New Material Techn. Ltd.) describes a two-stage synthesis for the synthesis of N-methyl-N-(2-chloroethyl) piperazine from amino diglycol (ADG) by means of N-methylpiperidin as an intermediate.

CN 102 304 101 A (Shaoxing Xingxin Chem. Co., Ltd.) N-alkyl piperazine Simultaneous preparation is carried out by reacting N-hydroxyethyl-1,2-ethanediamine with a primary _C1-7 alcohol in the presence of a metal catalyst.

DE 198 59 776 A1 (BASF AG) is a special amination process for forming a shaped catalytic body comprising an oxygen-containing compound of titanium and copper and metallic copper.

EP 382 049 A1 (BASF AG) discloses catalysts comprising oxygenates of zirconium, copper, cobalt and nickel, and processes for the hydroisthanation of alcohols. The preferred zirconia content of such catalysts is from 70% by weight to 80% by weight (cited above: page 2, last paragraph; page 3, paragraph 3; examples). These catalysts, while exhibiting good activity and selectivity, still exhibit improved service life. On page 4, lines 49-50 refer to the preparation of pipettes from polyols. And other compounds.

EP 696 572 A1 (BASF AG) relates to amination hydrogenation using a ZrO ₂ /CuO/NiO MoO ₃ catalyst. On page 4, lines 39-40 refer to the preparation of pipettes from polyols. And other compounds.

EP 963 975 A1 (BASF AG) describes amination hydrogenation using a ZrO ₂ /CuO/NiO/CoO catalyst.

EP 446 783 A2 (BASF AG) is especially concerned with N-aryl substituted pipe For the preparation, the preparation is carried out by amination of the corresponding N,N-bis(2-hydroxyalkyl)-N-arylamine.

EP 235 651 A1 (BASF AG) teaches the preparation of N-methylpiperidone from diethanolamine (DEOA) and monomethylamine (MMA) in the presence of a metal supported catalyst, more particularly a Cu-containing catalyst. Methods.

CN 1 413 991 A (Tianjing Univ.) describes N-β-hydroxyethyl ethylenediamine (AEEA) and derivatives at 120 ° C - 380 ° C and 0 to 100 bar above the Al ₂ O ₃ supported metal catalyst Formation of piperidine in the presence of H ₂ Reaction.

US 3,907,802 (Henkel & Cie Co., Ltd.) describes alkanolamines with long chain N-alkylation ("alkyl groups having 8 to 22 carbon atoms") with NH3 or monomethylamine (MMA) at 200 ° C to 350 The reaction in the presence of H ₂ over a specific chromium oxide/ZnO or alumina/ZnO catalyst at a molar ratio of 3-30 (NH ₃ /MEA: alkanolamine) at ° C and about 50 to 405 bar.

Patent application EP 12171084.2 (BASF SE) dated June 6, 2012 describes DEOA and NH ₃ at 180 ° C - 230 ° C and 50-300 bar, in the range of 1:5 to 1:20 Mohr ratio, reaction in the presence of H2 over a Cu-Ni-Co-Sn/A ₁₂ O ₃ catalyst.

Patent application EP 12170569.3 (BASF SE) of June 1, 2012 describes DEOA and monomethylamine (MMA) at 180 ° C - 230 ° C and 50-300 bar, ranging from 1:5 to 1:20 The internal molar ratio, the reaction in the presence of H ₂ over the Cu-Ni-Co-Sn/Al ₂ O ₃ catalyst.

Patent application EP 12171068.5 (BASE SE) dated June 6, 2012 describes DEOA and ammonia at 180 ° C to 220 ° C and 160 to 220 bar, with a range of 1:5 to 1:20 Ear ratio, the reaction in the presence of H ₂ over the Cu-Ni/ZrO ₂ catalyst.

One object of the present invention is to improve the existing preparation of the mono-N-alkyl pipe of formula I. Di-N-alkylpipe The economics of the method and the remedy of one or more of the disadvantages of the prior art. The intent is to find conditions that are technically easy to establish and allow the process to be carried out with high conversion, high yield, space time yield (STY) and selectivity, while the shaped catalyst has high mechanical stability and a low risk of "loss".

[Time-of-flight yield is reported as "product amount / (catalyst volume. time)" (kg / (l _catalyst.h )) and / or "product amount / (reactor volume. time)" (kg / (l _reactor) . h))].

Accordingly, an N-alkylpiper for the preparation of formula I has been found Methods

Wherein R ¹ is hydrogen (H), methyl or ethyl, and R ² is C ₁ to C ₅ alkyl by the N-substituted diethanolamine of formula II

Carrying out reaction with ammonia or a monoamine of the formula H ₂ NR ¹ (III) in the presence of hydrogen and a supported metal catalyst, wherein the catalytically active composition of the catalyst (before it is reduced by hydrogen) comprises from 20% by weight to 85% by weight of zirconium Oxygenate (calculated as ZrO ₂ ), 1 wt% to 30 wt% copper oxygenate (calculated as CuO), 14 wt% to 70 wt% nickel oxygenate (calculated as NiO), and 0 wt% to 5 wt% molybdenum An oxygenate (calculated as MoO ₃ ), and the reaction is carried out in the liquid phase at an absolute pressure in the range of from 160 to 240 bar at a temperature ranging from 180 ° C to 230 ° C. A molar ratio of from 5 to 50 (relative to the diethanolamine II used) using ammonia or a primary amine III, and from 0.1 wt% to 9.0 wt% based on the total amount of diethanolamine II and ammonia or amine III used It is carried out in the presence of hydrogen.

The group R ₁ is a H atom (hydrogen, H), a methyl group or an ethyl group.

The group R ₂ is C _1-5 alkyl, preferably C _1-3 alkyl, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, t-butyl, The third butyl group, n-pentyl group, isopentyl group, second pentyl group, neopentyl group or 1,2-dimethylpropyl group is preferably a methyl group or an ethyl group.

Accordingly, the primary amine III is more preferably monomethylamine (MMA) or monoethylamine (MEA).

An amine of formula I which can be preferably prepared by the process of the invention Wherein R ¹ is H and R ² is methyl or ethyl.

An amine of formula I which may also be preferably prepared by the process of the invention Wherein R1 is methyl or ethyl and R ² is methyl or ethyl. For example, N,N'-dimethylperazine And N-methyl-N'-ethylpipe The methyl group in the latter compound is derived from the MMA used (reacted with N-ethyldiethanolamine) or from the N-methyldiethanolamine used (reacted with MEA).

This method can be carried out continuously or in batches. Continuous mode is preferred.

In the recycle gas mode, the starting material (N-substituted DEOA II and ammonia or primary amine III) is vaporized in a recycle gas stream and supplied to the reactor as a gas.

The reactant (N-substituted DEOA and ammonia or primary amine III) can also be evaporated in the form of an aqueous solution and sent to the catalyst bed along with the recycle gas stream.

The preferred reactor is a tubular reactor. An example of a suitable reactor with a recycle gas stream is found in Ullmann's Encyclopedia of Industrial Chemistry, 5th Edition, Volume B4, pages 199-238, "Fixed-Bed Reactors". .

Alternatively the reaction is advantageously carried out in a shell-and-tube reactor or in a single-stream unit.

In a single stream apparatus, the tubular reactor in which the reaction is carried out may be comprised of a plurality of (e.g., two or three) individual tubular reactors in series. Possible and advantageous options here are intermediate introduction feeds (including N-substituted DEOA and/or ammonia or primary amines III and/or H2) and/or recycle gas and/or reactor emissions from downstream reactors. .

The circulating gas flow rate is preferably from 40 to 1500 m ^ 3 (at atmospheric pressure) / [m ^ 3 catalyst (bed volume). Within the range of hours, more specifically 100 to 1000 m ^ 3 (at atmospheric pressure) / [cubic meter catalyst (bed volume). Within the range of hours]. (atmospheric pressure = 1 bar absolute pressure)

The recycle gas preferably comprises at least 10 vol%, in particular from 50 vol% to 100 vol%, in particular from 80 vol% to 100 vol% hydrogen (H ₂ ).

In the process of the present invention, it is preferred to consist only of a catalytically active composition and, if a catalyst is used in the form of a shaped body, a forming aid optionally used, for example, such as graphite or stearic acid, and thus These catalysts are used in the form of a catalyst which does not contain other catalytically active concomitants. In this case, the oxidic support material zirconium dioxide (ZrO ₂ ) is considered to be a catalytically active composition.

In the case of zirconium dioxide, a monoclinic, tetragonal or cubic form is preferred. Single oblique Especially good.

Catalyst is used in a manner to catalyze the active composition (grinding to powder) Introduced into the reaction vessel, or the catalytically active composition (after grinding, mixing with the forming aid, shaping, and thermal conditioning) to form the catalytic body (eg, ingots, beads, rings, extrudates (eg, strands) Line)) is arranged in the reactor.

Concentration value of catalyst component (in wt%) unless otherwise indicated In each case, the catalytically active composition of the catalyst (after its final heat treatment and before its hydrogen reduction) is used.

The catalytically active composition of the catalyst after its final heat treatment and before its hydrogen reduction is defined as the sum of the mass of the catalytically active component and the mass of the aforementioned catalyst support material, and substantially comprises the following components: zirconium dioxide (ZrO ₂ ), And oxygen compounds of copper and nickel, and molybdenum as the case may be.

The sum of the components of the aforementioned catalytically active composition is typically from 70% by weight to 100% by weight, preferably from 80% by weight to 100% by weight, more preferably from 90% by weight to 100% by weight, specifically >95% by weight, and most specifically >98% by weight, more Specifically >99 wt%, such as especially preferred 100 wt%.

The catalyst of the present invention and the catalytically active composition of the catalyst employed in the process of the present invention may further comprise one or more elements (oxidation state 0) selected from Groups IA to VI A and IB to VII B and VIII of the Periodic Table of Elements or Its organic or inorganic compounds.

Examples of such elements and their compounds are as follows: transition metals such as Mn or MnO ₂ , Mo or MoO ₃ , W or tungsten oxide, Ta or cerium oxide, Nb or cerium oxide or cerium oxalate, V or vanadium oxide or vanadium Mercapto pyrophosphate; lanthanide such as Ce or CeO ₂ , or Pr or Pr ₂ O ₃ ; alkaline earth metal oxides such as SrO; alkaline earth metal carbonates such as MgCO ₃ , CaCO ₃ and BaCO ₃ ; , such as Na ₂ O, K ₂ O; alkali metal carbonates such as Li ₂ CO ₃ , Na ₂ CO ₃ and K ₂ CO ₃ ; and boron trioxide (B ₂ O ₃ ).

The catalytically active composition of the catalyst employed in the process of the invention preferably contains no antimony, no antimony, no iron and/or no zinc, and in each case neither in metallic form (oxidation state = 0) These materials are not contained in ionic form (oxidized state ≠0), especially in oxidized form.

The catalytically active composition of the catalyst employed in the process of the invention preferably contains no silver, in each case neither in metallic form (oxidized state = 0) nor in ionic form (oxidized state ≠0) (especially oxidized) Form) contains silver.

The catalytically active composition of the catalyst employed in the process of the invention preferably contains no cobalt, in each case neither in metallic form (oxidized state = 0) nor in ionic form (oxidized state ≠0) (especially oxidized Form) contains cobalt.

The catalytically active composition of the catalyst preferably does not contain an oxygenate of cerium and/or chromium.

The catalytically active composition of the catalyst preferably does not contain an oxygenate of titanium and/or aluminum.

In a particularly preferred embodiment, the catalyst of the present invention and the catalytically active composition of the catalyst employed in the process of the present invention do not contain other catalysis in elemental form (oxidation state = 0) or in ionic form (oxidation state ≠ 0). Active ingredient.

In a particularly preferred embodiment, the catalytically active composition is not doped with other metals or metal compounds.

However, the customary use of recovering Cu, Ni and/or Mo metals is accompanied by trace elements. Not in this column.

The catalyst can be produced by known methods, for example by precipitation, precipitation deposition Or impregnated.

Preferably, the heterogeneous catalyst comprises in its catalytically active composition (before hydrogen reduction)

20% by weight to 85% by weight, preferably 20% by weight to 65% by weight, more preferably 22% by weight to 40% by weight of zirconium-containing oxygen compound (calculated as ZrO ₂ ), 1% by weight to 30% by weight, more preferably 2% by weight to 25% by weight of copper-containing oxygen The compound, calculated as CuO, 14% by weight to 70% by weight, preferably 15% by weight to 50% by weight, more preferably 21% by weight to 45% by weight of the oxygen compound of nickel (calculated as NiO), and the nickel and copper molars are preferably more than 1, more Specifically, it is greater than 1.2, especially 1.8 to 8.5, and 0 wt% to 5 wt%, specifically 0.1 wt% to 3 wt% of molybdenum oxide (calculated as MoO ₃ ).

A particularly preferred heterogeneous catalyst in the process of the invention is

Catalysts which are disclosed in EP 382 049 A (BASE AG) or which can be prepared accordingly, the catalytically active composition (before treatment with hydrogen) comprises

20% by weight to 85wt%, preferably 70% by weight to 80% by weight of ZrO ₂ , 1% by weight to 30% by weight, preferably 1% by weight to 10% by weight of CuO, and in each case, 1% by weight to 40% by weight, preferably 5% by weight to 20% by weight of NiO; a catalyst disclosed in EP 696 572 A1 (BASF AG), whose catalytically active composition (before hydrogen reduction) comprises 20% to 85% by weight of ZrO ₂ , 1% to 30% by weight of copper oxygen Compound (calculated as CuO), 30 wt% to 70 wt% of nickel oxygenate (calculated as NiO), 0.1 wt% to 5 wt% of molybdenum oxide (calculated as MoO ₃ ), and 0 wt% to 10 wt% of aluminum and/or Or an oxygen-containing compound of manganese (calculated as Al ₂ O ₃ and MnO ₂ , respectively), an example of which is a catalyst disclosed on page 8 of the above-mentioned citation, having a composition of 31.5 wt% ZrO ₂ , 50 wt% NiO, 17 wt% CuO, and 1.5 wt. % MoO ₃ .

The resulting catalyst can be stored as it is. In its use as a method of the invention The catalyst was previously subjected to pre-reduction (catalyst activation) by treatment with hydrogen. Alternatively, it can be used without prior reduction, in which case it is reduced (activated) by the hydrogen present in the reactor under the conditions of the process of the invention.

For activation, preferably between 100 ° C and 500 ° C, specifically 150 ° C to The catalyst is exposed to a hydrogen atmosphere or an atmosphere containing hydrogen at a temperature of 400 ° C, specifically 180 ° C to 300 ° C, for at least 25 minutes, specifically for a period of at least 60 minutes. The catalyst activation time can be combined up to one hour, in particular up to 12 hours, more specifically up to 24 hours.

During the activation process, some of the oxygen-containing metal compounds present in the catalyst are also The same is true for the oxometal compound which is present in the active form of the catalyst together with the various oxygen compounds.

The process of the invention is preferably carried out continuously, wherein the catalyst is preferably arranged in the reactor in the form of a fixed bed. This fixed catalyst bed can be accessed by a fluid from above or below.

In each case, the primary amine III or ammonia is preferably 5 to 50 times the molar amount, more specifically 10 to 45 times the molar amount, based on the N-substituted DEOA II used. It is used in an amount of 20 to 40 times the amount of moles, for example, 25 or 30 times the amount of moles.

The primary amine III or ammonia may be used in the form of an aqueous solution, specifically a 30% by weight to 100% by weight aqueous solution, for example, a 50% by weight to 85% by weight aqueous solution. Also especially when derived from the recovery from reaction effluents, monomethylamine and monoethylamine are preferably also used without other solvents (compressed gas, especially in the range of 95% to 100% by weight).

The N-substituted DEOA II is preferably used in the form of an aqueous solution, in particular, a 75 wt% to 99 wt% aqueous solution, for example, an 80 wt% to 90 wt% aqueous solution.

Preferably, the operation is 5 to 800 standard cubic meters / (cubic meter catalyst ‧ hours), More specifically, the exhaust gas flow rate of 20 to 300 standard cubic meters / (cubic meter catalyst ‧ hours). [Standard cubic meters = volume converted to standard conditions (20 ° C, 1 bar absolute pressure)].

Amination of the primary alcohol group of the N-substituted DEOA II is carried out in the liquid phase. excellent Consider the fixed bed method in the liquid phase first.

Reactant (N-substituted DEOA II and primary amine) when operating in the liquid phase III or ammonia) is preferably in the liquid phase at 16.0 to 24.0 MPa (160 to 240 bar), preferably 17.0 to 23.0 MPa, more preferably 18.0 to 22.0 MPa, still more preferably 19.0 to 21.0 MPa, and very preferably 19.5 to 20.5. At a pressure of MPa, and at a temperature of generally 180 ° C to 230 ° C, specifically 180 ° C to 220 ° C, preferably 185 ° C to 210 ° C, more specifically 190 ° C to 200 ° C simultaneously through the catalyst (including hydrogen), The catalyst is typically positioned in a fixed bed reactor that is preferably externally heated. Both the trickle mode and the liquid phase mode can be used. The catalyst space velocity is generally in the range of 0.1 to 1.0, preferably 0.15 to 0.7, more preferably 0.15 to 0.6, more preferably 0.2 to 0.4 kg of N-substituted DEOA II per liter of catalyst (bed volume) (N- The substituted DEOA II is calculated in 100% form). The reactants may optionally be diluted with a suitable solvent such as water, tetrahydrofuran, dioxane, N-methylpyrrolidone or ethylene glycol dimethyl ether. The reactants are suitably heated, preferably to the reaction temperature, even before they are supplied to the reaction vessel.

The reaction preferably uses a catalyst space velocity in the range of 40 to 1500 liters (stp) of hydrogen per liter of _catalyst per hour, specifically between 100 and 1000 liters (stp) of hydrogen per liter of _catalyst . The catalyst space velocity in the range is carried out.

[liters (stp) = Nl = body converted to standard conditions (20 ° C, 1 bar absolute pressure) product].

The value used for the catalyst volume is always related to the bed volume.

In each case, based on the total amount of diethanolamine II and ammonia or amine III [i.e., diethanolamine II (NH ₃ or amine III)], the reaction is in the presence of 0.1 wt% to 9.0 wt% hydrogen, specifically in the presence of It is carried out in the presence of 0.25 wt% to 7.0 wt% of hydrogen, more preferably in the presence of 0.3 wt% to 6.0 wt% of hydrogen, specifically in the presence of 0.4 wt% to 5.0 wt% of hydrogen.

The pressure in the reaction vessel consists of the sum of the partial pressures of the primary amine III or ammonia, the N-substituted DEOA II and the resulting reaction product, and optionally the solvent used at the stated temperature, by injection. Hydrogen is effectively raised to the desired reaction pressure.

In the case of continuous operation in the liquid phase, excess primary amine III can be circulated with hydrogen.

If the catalyst is arranged in the form of a fixed bed, it may be advantageous to have a shaped catalyst in the "dilution" reactor, for example, by mixing the shaped catalyst with an inert filler. The proportion of filler in the catalyst preparations may total from 20 to 80, specifically 30 to 60, and more specifically 40 to 50 parts by volume.

The reaction water formed during the reaction (in each case the conversion of each mole group to form one mole of water) generally does not have an adverse effect on the conversion, reaction rate, selectivity or catalyst life, and is therefore beneficial only in The reaction product is removed from the product (e.g., by distillation).

After the reaction effluent has been depressurized, the excess hydrogen present and any excess aminating agent are advantageously removed from the reaction effluent and the resulting crude reaction product is purified by, for example, fractional rectification. Suitable treatment methods are described, for example, in EP 1 312 600 A and EP 1 312 599 A (both BASF AG). Excess primary amine and hydrogen are advantageously recycled to the reaction zone. The same applies to any N-substituted DEOA II that is incompletely reacted.

The reaction product is preferably treated as follows: from the reaction product, by distillation

(i) first remove any unreacted amine III or any unreacted ammonia at the top, (ii) remove water at the top, and (iii) remove at the top any lower point boiling below the boiling point of product I of the process Product, (iv) remove the N-alkyl piperate at the top The I process product, and any by-products (high boiling compounds) having a boiling point higher than the boiling point of the product I of the process, and any unreacted N-substituted DEOA II present remain in the liquid phase.

The alkylaminoethylethanolamine of formula IV during the reaction in the process of the invention

Can be formed as a by-product.

Therefore, and especially by distillation

(v) from the liquid phase of step iv, removing any unreacted N-substituted DEOA (II) at the top and/or any alkylaminoethylethanolamine of formula IV present as a by-product, and Circulate to the reaction.

The purity removed in step i is from 90 wt% to 99.9 wt%, specifically 95 wt% to 99.9 wt% of the amine III or ammonia is preferably recycled to the reaction, and more preferably, the amine removed Part III or a portion of ammonia, specifically 1 wt% to 30 wt% of the amine III or ammonia removed, more specifically 5 wt% to 25 wt% of the removed amine III or ammonia is removed from the cycle.

All pressure data is related to absolute pressure.

All ppm values are related to quality.

Example

1. Preparation of Catalyst A

Catalyst A (Cu/Ni/Mo/ZrO ₂ catalyst, as disclosed in EP 696 572 A1 (BASF AG)) was prepared by precipitation, filtration, thermal conditioning and ingot (6 x 3 mm ingot). The catalyst had the following composition (before it was treated (activated) with hydrogen): 50 wt% NiO, 17 wt% CuO, and 15 wt% MoO ₃ on ZrO ₂ (31.5 wt%).

2. Reaction of N-substituted DEOA (II, R ² = ethyl) with ammonia in a continuously operated tubular reactor

A glass bead (250 ml) was filled in the lower half of the heated tubular reactor having an inner diameter of 14 mm and a thermocouple centered at a total volume of 1000 ml, and 500 ml of catalyst A was filled over the layer, and finally the glass was again used. The beads fill the rest. Prior to the reaction, the catalyst was activated at atmospheric pressure (25 l (stp) / h) at no more than 280 ° C for 24 hours [l (stp) = liter (stp) = conversion to standard conditions (20 ° C , 1 bar absolute pressure) volume]. From the bottom to the top through the reactor were 300 g/h E-DEOA (85 wt% aqueous solution), 1150 g/h or 1725 g/h ammonia and 400 l (stp)/h hydrogen. The reactor was maintained at a temperature of from about 190 ° C to 195 ° C and a total pressure of 200 bar. The reaction temperature was chosen such that the conversion of the obtained E-DEOA was >90%. The mixture from the reactor is allowed to cool and depressurize to atmospheric pressure. At various time points, samples were taken from the reaction mixture and analyzed by gas chromatography.

The results can be seen in Table I below.

Sel.: Selectivity

NEtPIP: monoethylperidazole (N-ethyl-piperidine )

DEtPIP: diethylpiper (N,N'-diethyl-piperidine )

E-DEOA: N-ethyl-diethanolamine

deal with

The treatment is preferably carried out by the following five steps (here, the reaction of N-methyl-DEOA with ammonia is used as an example):

1) Remove unreacted ammonia and recycle to the reactor

A portion of the ammonia is removed from the cycle from the top of the column as appropriate.

2) Remove water

3) remove the boiling point lower than N-methyl pipe Secondary component of boiling point

4) N-methyl piperazine from the top Purified distillation is accompanied by the removal of higher boiling secondary components by means of a liquid phase.

5) returning a portion of the higher boiling secondary component, more specifically N-methyldiethanolamine, R ¹ =H and R ² =methyl, to the alkylaminoethylethanolamine of formula IV, as appropriate in.

Claims (27)

An N-alkylpipeper for preparing formula I Methods Wherein R ¹ is hydrogen (H), methyl or ethyl, and R ² is C ₁ to C ₅ alkyl by the N-substituted diethanolamine of formula II Carrying out reaction with ammonia or a monoamine of the formula H ₂ NR ¹ (III) in the presence of hydrogen and a supported metal catalyst, wherein the catalytically active composition of the catalyst (before it is reduced by hydrogen) comprises from 20% by weight to 85% by weight of zirconium Oxygenate (calculated as ZrO ₂ ), 1 wt% to 30 wt% copper oxygenate (calculated as CuO), 14 wt% to 70 wt% nickel oxygenate (calculated as NiO), and 0 wt% to 5 wt% molybdenum Oxygenate (calculated as MoO ₃ ), and the reaction is in the liquid phase at an absolute pressure in the range of 160 to 240 bar, at a temperature ranging from 180 ° C to 230 ° C, to 5 A molar ratio of 50 to 50 (relative to the diethanolamine II used) is carried out using ammonia or a primary amine III, and in the presence of 0.1% by weight to 9.0% by weight of hydrogen based on the total amount of diethanolamine II and ammonia or amine III used. The method of claim 1, wherein the catalytically active composition of the catalyst (before it is reduced by hydrogen) comprises from 20 wt% to 65 wt% of zirconium oxygenate (calculated as ZrO ₂ ). The method of claim 1 or 2, wherein the catalytically active composition of the catalyst (before it is reduced by hydrogen) comprises from 2 wt% to 25 wt% of copper oxygenate (calculated as CuO). The method of any of the preceding claims, wherein the catalytically active composition of the catalyst (before it is reduced by hydrogen) comprises 15 wt% to 50 wt% of an oxygenate of nickel (calculated as NiO). The method of any one of the preceding patent application in any range, wherein the catalyst composition of the catalytically active (by reduction with hydrogen before it) containing 0.1wt% to 3wt% of oxygen compounds of molybdenum (calculated as MoO _3). The method of any of the preceding claims, wherein the molar ratio of nickel to copper in the catalyst is greater than one. The method of any of the preceding claims, wherein the catalytically active composition of the catalyst does not contain ruthenium and/or osmium. The method of any of the preceding claims, wherein the catalytically active composition of the catalyst does not contain iron and/or zinc. The method of any of the preceding claims, wherein the catalytically active composition of the catalyst does not contain cobalt. The method of any of the preceding claims, wherein the catalytically active composition of the catalyst does not contain an oxygen-containing compound of cerium and/or aluminum and/or titanium. The method of any of the preceding claims, wherein the reaction is carried out at a temperature ranging from 185 °C to 220 °C. The method of any of the preceding claims, wherein the reaction is carried out at an absolute pressure in the range of from 170 to 230 bar. A method according to any one of the preceding claims, wherein the ammonia or the primary amine II is used in an amount of from 10 to 45 times the molar amount of the N-substituted diethanolamine II used. A process according to any one of the preceding claims, wherein the reaction is carried out in the presence of from 0.25 wt% to 7.0 wt% hydrogen based on the total amount of DEOA and ammonia used. The method of any of the preceding claims, wherein the catalyst is arranged in the form of a fixed bed Listed in the reactor. The method of any of the preceding claims, which is carried out continuously. The method of any one of the preceding claims, wherein the reaction is carried out in a tubular reactor. The method of any one of the preceding claims, wherein the reaction is carried out in a recycle gas mode. A method according to any one of the preceding claims, wherein the N-substituted diethanolamine II is used in the form of an aqueous solution. A method according to any one of the preceding claims, wherein the primary amine III or the ammonia is used in the form of an aqueous solution. A process according to any one of the preceding claims, wherein the reaction is carried out at a catalyst space velocity in the range of from 0.1 to 1.0 kg of N-substituted diethanolamine II / (liter _catalyst . hours). A process according to any one of the preceding claims, wherein the reaction is carried out at a catalyst space velocity in the range of from 100 to 1000 liters (stp) of hydrogen per liter of _catalyst . A process according to any one of the preceding claims, wherein R ¹ is H and R ² is methyl or ethyl by reacting N-methyldiethanolamine or N-ethyldiethanolamine with ammonia Mono-N-alkyl pipe of formula I . A process according to any one of the preceding claims, wherein R ¹ is methyl or B by reacting N-methyldiethanolamine or N-ethyldiethanolamine with monomethylamine or dimethylamine Di-N-alkyl pipe of formula I wherein R ² is methyl or ethyl . A process according to any one of the preceding claims, wherein from the reaction product, by distillation, (i) first removing any unreacted amine III or any unreacted ammonia at the top, (ii) moving at the top In addition to water, (iii) removing any by-products having a boiling point lower than the boiling point of product I of the process at the top, (iv) removing the N-alkyl pipeper at the top The I process product, and any by-product having a boiling point higher than the boiling point of the product I of the process, and any unreacted N-substituted diethanolamine II present remain in the liquid phase. A process as claimed in the preceding claims, wherein (v) is separated from the liquid phase of step iv by distillation, and any unreacted N-substituted diethanolamine II present and/or as a by-product are present at the top. Any alkylaminoethylethanolamine of formula IV And recycled to the reaction. The method of any one of the preceding claims, wherein the amine III or ammonia having a purity of 90 wt% to 99.9 wt% removed in step i is recycled to the reaction, and the amine III or ammonia A portion of it is preferably removed from the cycle.