Process for the preparation of 1,4-diazabicyclo ¬2,2,2 octanes

0001The present invention relates to a new and improved process for the preparation of 1,4-diazabicyclooctanes by reacting piperazines in the presence of heterogeneous catalysts at elevated temperatures.

0002According to US Pat. No. 3,772,293, 1,4-diazabicyclo-2,2,2-octanes are made from piperazine and ethylene oxide, according to DE-A-24 42 929 from N, N'-dihydroxyethylpiperazine with elimination of glycol, according to EP-A- 158 319, DE-A-24 34 913, US-A-3,166,588 and EP-A-111,928, for example from N-hydroxyethyl- or N-aminoethyl-piperazine or according to US-A-3,883,533 from 1,4-bis- (formyl ) -piperazine and ethylene glycol.

0003Phosphates of Ca, Sr, Ba, Zn, La, Al, Co, Ni or Ce or aluminum silicate zeolites of the pentasil type, A zeolites or silica-alumina cracking catalysts were used as heterogeneous catalysts.

0004The known processes provide unsatisfactory yields and / or selectivities and / or undesirable, difficult or incompletely separable by-products occur.

0005The object of the invention was therefore to find better access to the 1,4-diazabicyclo-2,2,2-octanes and to remedy the disadvantages of the known processes.

0006Accordingly, a new and improved process for the preparation of 1,4-diazabicyclo-2,2,2-octanes has been found, which is characterized in that piperazines which carry hydrogen or an alkyl group on their nitrogen atoms, in the presence of heterogeneous catalysts at temperatures from 50 to 600 ° C and pressures from 0.01 to 50 bar, optionally with the use of a suitable solvent or diluent.

0007The 1,4-diazabicyclo-2,2,2-octanes I can be obtained by the following method:

0008The reaction is carried out by thermal treatment of piperazines on a heterogeneous catalyst.

0009The reaction can be carried out both in the liquid phase and in the discontinuous or preferably continuous gas phase at 50 to 600 ° C. and 0.01 to 50 bar.

0010The liquid phase reaction can be carried out, for example, as a suspension, trickle or bottom reaction at temperatures from 50 to 200 ° C. and pressures from 0.5 to 20 bar, preferably at temperatures from 70 to 170 ° C. and pressures from 1 to 5 bar.

0011The preferred gas phase reaction can be carried out, for example, at temperatures from 100 to 600 ° C., preferably at 150 to 500 ° C. and pressures from 0.1 to 50 bar, particularly preferably at 200 to 400 ° C. and pressures from 0.5 to 5 bar . In the reaction in the gas phase, a catalyst load of 0.1 to 20, in particular 0.5 to 5, g of starting material of the formula II is advantageously maintained per g of catalyst and hour (WHSV = g feed mixture / g of catalyst and hour). The gas phase reaction can be carried out in a fixed bed or in a fluidized bed.

0012After the reaction, the products formed are isolated from the reaction mixture by customary processes, for example by distillation; unreacted starting materials are optionally returned to the reaction.

0013Gaseous reaction products are preferably introduced immediately into a separation and, for example, broken down into their individual components in a fractionation column.

0014The Piperazines II can be used without, but preferably with, solvents or diluents. Organic solvents or diluents such as aliphatic or alicyclic alcohols, for example, are suitable as such C₁ to C₁₂ alkanols, preferably C₁ to C₆ alcohols, particularly preferably methanol and ethanol, C₅ to C₂₀ cycloalkanols, preferably cyclohexanol, diols such as C₁ to C₁₂ hydroxyalkanols, preferably C₁ to C₄ hydroxyalkanols such as ethylene glycol , Butanediols and hexanediols, acyclic or cyclic ethers with 2 to 12 carbon atoms, such as dimethyl ether, diethyl ether, dibutyl ether, dipropyl ether, dipentyl ether or their isomers and THF, pyran or lactones, polyethers, such as monoglyme, diglyme, Triglyme, aromatic or aliphatic hydrocarbons such as benzene, toluene, xylene, pentane, cyclopentane, hexane and petroleum ether or mixtures thereof and especially water or aqueous organic solvents or diluents of the type mentioned above.

0015The concentration of the piperazines II in water can be between 5 and 95% by weight, preferably between 20 and 60% by weight. The molar ratio of organic solvent or diluent to piperazine II can be 0.1: 1 to 50: 1, preferably 1: 1 or 15: 1.

0016Inert gases such as nitrogen or argon, and in some cases oxygen, are also suitable as diluents for the gas phase.

0017The substituents R¹ and R² in the formulas I and II have the following meanings independently of one another: - hydrogen, unbranched or branched C₁ to C₄ alkyl such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl and tert-butyl, preferably methyl and ethyl, - Unbranched or branched C₂ to C₄ alkenyl such as vinyl, allyl and butenyl.

0018The substituent R³ in formula II means hydrogen or C₁- to C₈-alkyl such as methyl, ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl, sec-butyl, tert-butyl, pentyl, hexyl and Octyl.

0019Solid heterogeneous catalysts, preferably acidic solid heterogeneous catalysts, are used as catalysts for the process according to the invention.

0020Acidic zeolitic catalysts are used in particular as catalysts for the process according to the invention. Zeolites are crystalline aluminosilicates, which have a highly ordered structure with a rigid three-dimensional network of SiO₄ and AlO₄ tetrahedra, which are connected by common oxygen atoms. The ratio of Si and Al atoms to oxygen is 1: 2 (see Ullmann's Encyclopedia of Technical Chemistry, 4th Edition, Volume 24, page 575 (1983)). The electrovalence of the tetrahedra containing aluminum is compensated for by the inclusion of cations in the crystal, for example an alkali metal or hydrogen ion. A cation exchange is possible. The spaces between the tetrahedra are occupied by drying or calcining water molecules before dehydration.

0021In the zeolite, other elements such as B, Ga, Fe, Cr, V, As, Sb, Bi or Be or mixtures thereof can be built into the lattice instead of aluminum, or the silicon can be replaced by a tetravalent element such as Ge, Ti, Zr, Hf to be replaced.

0022According to their structure, zeolites are divided into different groups (see Ullmann's Encyclopedia of Technical Chemistry, 4th Edition, Vol. 24, p. 575 [1983]). In the case of the mordenite group, chains or in the case of the chabasite group, layers of tetrahedra form the zeolite structure, while in the faujasite group the tetrahedra are arranged in polyhedra, for example in the form of a cubo-octahedron which is built up from four rings or six rings. Depending on the connection of the cubo-octahedron, which creates voids and pores of different sizes, a distinction is made in zeolites of type A, L, X or Y.

0023Catalysts suitable for the process according to the invention are zeolites from the mordenite group or narrow-pore zeolites of the erionite or chabasite type or zeolites of the faujasite type, for example Y, X or L zeolites. The so-called "ultra-stable" zeolites of the faujasite type, ie dealuminated zeolites, also belong to this group of zeolites. Methods for producing such zeolites are described in "catalysis by Zeolites", volume 5 from "studies in Surface Science and Catalysis", ed. B. Imelik et. al. Elsevier Scientific Publishing Comp., 1980, p. 203 and "Crystal Structures of Ultra-stable Faujasites", Advances in Chemistry, Series No. 101, American Chemical Society Washington, DC, p. 226ff (1971) and in U.S. Patent No. 4 512 961.

0024Zeolites of the pentasil type are particularly advantageous. As a basic building block, they share a five-membered ring made of SiO T tetrahedra. They are characterized by a high SiO₂ / Al₂O₃ ratio and by pore sizes between those of type A zeolites and those of type X or Y (cf. Ullmann's Encyclopedia of Technical Chem., 4th ed., Vol. 24, 1983).

0025These zeolites can have different chemical compositions. These are alumino, boro, iron, beryllium, gallium, chromium, arsenic, antimony and bismuth silicate zeolite or their mixtures, and alumino, boro, gallium and iron germanate zeolites or their mixtures. The alumino, borosilicate and iron silicate zeolites of the pentasil type are particularly suitable for the process according to the invention. The aluminosilicate zeolite is, for example from an aluminum compound, preferably Al (OH) ₃ or Al₂ (SO₄) ₃ and a silicon component, preferably highly disperse silicon dioxide in aqueous amine solution, in particular in polyamines such as 1,6-hexanediamine or 1,3-propanediamine or triethylene tetramine solution with or in particular produced at 100 to 200 ° C under autogenous pressure without the addition of alkali or alkaline earth. This also includes the isotactic zeolites according to EP 34 727 and EP 46 504. The aluminosilicate zeolites obtained contain an SiO₂ / Al₂O₃ ratio of 10 to 40,000, depending on the amount of starting material used. Such aluminosilicate zeolites can also be synthesized in an ethereal medium such as diethylene glycol dimethyl ether, in an alcoholic medium such as methanol or 1,4-butanediol or in water.

0026The borosilicate zeolite is synthesized, for example, at 90 to 200 ° C. under autogenous pressure by using a boron compound, for example H₃BO₃, with a silicon compound, preferably highly disperse silicon dioxide in aqueous amine solution, in particular in 1,6-hexanediamine or 1,3-propanediamine or Triethylenetetramine solution with and especially without adding alkali or alkaline earth metal to react. This also includes the isotactic zeolites according to EP 34 727 and EP 46 504. Such borosilicate zeolites can also be prepared if the reaction is carried out instead of in an aqueous amine solution, for example in diethylene glycol dimethyl ether or in an alcoholic solution, for example 1,6-hexanediol.

0027The iron silicate zeolite is obtained, for example, from an iron compound, preferably Fe (SO₄) ₃ and a silicon compound, preferably highly disperse silicon dioxide in aqueous amine solution, in particular 1,6-hexanediamine, with or without addition of alkali metal or alkaline earth metal at 100 to 220 ° C. under autogenous pressure.

0028The silicon-rich zeolites that can be used (SiO₂ / Al₂O₃ ≧ 10) also include the so-called ZSM types, ferrierite, NU-1 and Silicalit® (a molecular sieve, a so-called silica polymorph).

0029The alumino, borosilicate and iron silicate zeolites thus produced can, after their isolation, drying at 100 to 160 ° C., preferably 110 ° C. and calcination at 450 to 550 ° C., preferably 500 ° C., with a binder in a ratio of 90:10 to 40: 60% by weight to be shaped into strands or tablets. Various aluminum oxides, preferably boehmite, amorphous aluminosilicates with an SiO₂ / Al₂O₃ ratio of 25:75 to 90: 5, preferably 75:25, silicon dioxide, preferably highly disperse SiO₂, mixtures of highly disperse SiO₂ and highly disperse Al₂O₃, TiO₂, ZrO₂ are suitable as binders as well as sound. After shaping, the extrudates or compacts are dried at 110 ° C / 16 h and calcined at 500 ° C / 16 h.

0030Advantageous catalysts are also obtained if the isolated alumino or. Borosilicate zeolite is deformed immediately after drying and is only subjected to calcination after the deformation. The aluminosilicate and borosilicate zeolites produced can be used in pure form, without binders, as strands or tablets, for example as transplants or peptizing aids Ethyl cellulose, stearic acid, potato starch, formic acid, oxalic acid, acetic acid, nitric acid, ammonia, amines, silicon esters and graphite or mixtures thereof can be used.

0031If the zeolite is not in the catalytically active, acidic H form but, for example, in the Na form due to the way in which it is produced, then this can be completely or partially converted into the desired H by ion exchange, for example with ammonium ions and subsequent calcination or by treatment with acids -Form to be transferred.

0032If a deactivation due to coke separation possibly occurs when using the zeolitic catalysts according to the invention, it is advisable to regenerate the zeolites by burning off the coke deposit with air or with an air / N 2 mixture at 400 to 550 ° C., preferably. This gives the zeolites their initial activity.

0033By partial coking (pre-coke) it is possible to adjust the activity of the catalyst for an optimal selectivity of the desired reaction product.

0034In order to achieve the highest possible selectivity, high turnover and long service lives, it can be advantageous to modify the zeolites. A suitable modification of the catalysts is, for example, that the undeformed or deformed zeolite is doped with metal salts by ion exchange or by impregnation. As metals, alkali metals such as Li, Cs, K, alkaline earth metals such as Mg, Ca, Sr, metals of the 3rd, 4th and 5th Main group such as Al, Ga, Ge, Sn, Pb, Bi, transition metals of the 4th - 8th subgroup such as Ti, Zr, V, Nb, Cr, Mo, W, Mn, Re, Fe, Ru, Os, Co, Rh , Sr, Ni, Pd, transition metals of the 1st and 2nd subgroup such as Cu, Ag, Zn, rare earth metals such as La, Ce, Pr, Nd, kFr, Yb and U are used.

0035The doping is expediently carried out in such a way that, for example, the deformed zeolite is placed in a riser tube and, for example, an aqueous or ammoniacal solution of a halide or a nitrate of the above-described metals is passed at 20 to 100 ° C. Such an ion exchange can be carried out, for example, on the hydrogen, ammonium and alkali form of the zeolite. A further possibility of applying metal to the zeolite is given by impregnating the zeolitic material with, for example, a halide, a nitrate or an oxide of the above-described metals in aqueous, alcoholic or ammoniacal solution. Both ion exchange and impregnation are followed by at least one drying step, optionally a further calcination.

0036A possible embodiment is, for example, that Cu (N0₃) ₂ x3 H₂O or Ni (NO₃) ₂ x 6 H₂O or La (NO₃) ₂ x 6 H₂O or Cs₂CO₃ is dissolved in water. With this solution, the deformed or undeformed zeolite is soaked for a certain time, approx. 30 minutes. Any excess solution is freed of water on a rotary evaporator. The soaked zeolite is then dried at approximately 150 ° C. and calcined at approximately 550 ° C. This impregnation process can be carried out several times in succession to set the desired metal content.

0037It is also possible, for example, to prepare an aqueous Ni (CO₃) ₂ solution or ammoniacal Pd (NO₃) ₂ solution and to slurry the pure powdered zeolite at 40 to 100 ° C. with stirring for about 24 hours. After filtering, drying at approx. 150 ° C and calcination at approx. 500 ° C, the zeolitic material obtained in this way can be processed further with or without a binder to form strands, pellets or fluidized material.

0038An ion exchange of the zeolites present in the H form or ammonium form or alkali form can be carried out in such a way that the zeolites are introduced in strands or pellets in a column and, for example, an aqueous Ni (NO₃) ₂ solution or ammoniacal Pd (NO₃) ₂ solution at a slightly elevated temperature between 30 and 80 ° C in the circuit for 15 to 20 h. It is then washed out with water, dried at approx. 150 ° C and calcined at approx. 550 ° C. For some metal-doped zeolites, for example Pd, Cu, Ni doped zeolites, an aftertreatment with hydrogen is advantageous.

0039Another possibility of modification consists in subjecting the zeolitic material - deformed or undeformed - to treatment with acids such as hydrochloric acids, hydrofluoric acid and phosphoric acid and / or water vapor. It is advantageous to proceed, for example, by treating zeolites in powder form with 1N phosphoric acid at 80 ° C. for 1 hour. After the treatment, it is washed with water, dried at 110 ° C./16 hours and calcined at 500 ° C./20 hours. According to another procedure, zeolites are treated with binders before or after their shaping, for example for 1 to 3 hours at temperatures from 60 to 80 ° C. with a 3 to 25% by weight, in particular 12 to 20% by weight, aqueous hydrochloric acid. The treated zeolite is then washed with water, dried and calcined at 400 ° C to 500 ° C.

0040A special embodiment for the acid treatment consists in treating the zeolitic material with hydrofluoric acid, which is generally used as 0.001 n to 2 n, preferably 0.05 n to 0.5 n, of hydrofluoric acid, for example before it is deformed at elevated temperature by heating under reflux for a period of generally 0.5 to 5, preferably 1 to 3 hours. After isolation, e.g. by filtering and washing out the zeolitic material, this is expediently dried, for example at temperatures from 100 to 160 ° C., and calcined at temperatures of generally 450 to 600 ° C. According to a further preferred embodiment for the acid treatment, the zeolitic material is, after being deformed with a binder, at elevated temperature, advantageously at temperatures from 50 to 90 ° C., preferably 60 to 80 ° C., for a period of 0.5 to 5, preferably with 12 to 20% by weight hydrochloric acid, treated . The zeolitic material is then generally washed out and expedient, for example at temperatures of 100 to 160 ° C, dried and calcined at temperatures of generally 450 to 600 ° C. HF treatment can also be followed by HCl treatment.

0041According to a different procedure, zeolites can be modified by applying phosphorus compounds such as trimethoxy phosphate, trimethoxy phosphine, primary, secondary or tertiary sodium phosphate. The zeolites are soaked in strand, tablet or fluidized form with aqueous H₃PO₄ solution, dried at 110 ° C and calcined at 500 ° C.

0042Further catalysts for the process according to the invention are phosphates, in particular aluminum phosphates, silicon aluminum phosphates, silicon iron aluminum phosphates, cobalt aluminum phosphates, cerium phosphate, zirconium phosphates, boron phosphate, iron phosphate, strontium phosphates or mixtures thereof.

0043Aluminum phosphates which have a zeolite structure, in particular those synthesized under hydrothermal conditions, are used as aluminum phosphate catalysts for the process according to the invention.

0044The aluminum phosphates produced under hydrothermal conditions are, for example, APO-5, APO-9, APO-11, APO-12, APO-14, APO-21, APO-25, APO-31 and APO-33. Syntheses of these compounds are described in EP-A-132 708, US 4,310,440 and US 4,473,663.

0045For example, the AlPO₄-5 (APO-5) is synthesized by homogeneously mixing orthophosphoric acid with pseudoboehmite (Catapal SB®) in water; tetrapropylammonium hydroxide is added to this mixture and then reacted at about 150 ° C. for 20 to 60 hours under autogenous pressure in an autoclave. The filtered AlPO₄ is dried at 100 to 160 ° C and calcined at 450 to 550 ° C.

0046AlPO₄-9 (APO-9) is also synthesized from orthophosphoric acid and pseudoboehmite but in aqueous DABCO solution (1,4-diazabicyclo-2,2,2-octane) at approx. 200 ° C under autogenous pressure for 200 to 400 h .

0047The AlPO₄-21 (APO-21) is synthesized from orthophosphoric acid and pseudoboehmite in aqueous pyrrolidone solution at 150 to 200 ° C. under autogenous pressure for 50 to 200 h.

0048The silicon aluminum phosphates used for the process according to the invention are, for example, SAPO-5, SAPO-11, SAPO-31 AND SAPO-34. The synthesis of this compound is described, for example, in EP 103 117, US 4,440,871. SAPO'S are produced by crystallization from an aqueous mixture at 100 to 250 ° C. and autogenous pressure for 2 h to 2 weeks, the reaction mixture being reacted from a silicon, aluminum and phosphorus component in aqueous amino-organic solutions.

0049SAPO-5, for example, is obtained by mixing SiO₂ suspended in aqueous tetrapropylammonium hydroxide solution with an aqueous suspension of pseudoboehmite and orthophosphoric acid and subsequent reaction at 150 to 200 ° C for 20 to 200 hours under autogenous pressure in a stirred autoclave. The filtered powder is dried at 110 to 160 ° C and the calcination at 450 to 550 ° C.

0050Precipitated aluminum phosphates can also be used as phosphate catalysts in the process. For example, such an aluminum phosphate is produced by dissolving 92 g of diammonium hydrogen phosphate in 700 ml of water. 260 g of Al (N0₃) ₃ x H₂O in 700 ml of water are added dropwise to this solution over 2 h. The pH is kept at pH 8 by the simultaneous addition of 25% NH₃ solution. The resulting precipitate is stirred for 12 h, then suction filtered and washed out. It is dried at 60 ° C / 16 h.

0051Boron phosphates for the process according to the invention can be prepared, for example, by mixing and kneading concentrated boric acid and phosphoric acid and then drying and calcining in an inert gas, air and steam atmosphere at 250 to 650 ° C., preferably 300 to 500 ° C.

0052Impregnation (impregnation and spraying) or, in some cases, modification components by ion exchange, as described above for the zeolites, can also be applied to these phosphates. As with the zeolite catalysts, it can also be modified with acids.

0053Suitable acidic catalysts are, for example, the acidic oxides of elements of III. and IV. main group and IV. to VI. Sub-group of the periodic system, in particular oxides such as silicon dioxide in the form of silica gel, diatomaceous earth, quartz, also titanium dioxide, zirconium dioxide, phosphorus oxides, vanadium oxides, niobium oxides, boron oxides, aluminum oxides, chromium oxides, molybdenum oxides, tungsten oxides or pumice or mixtures of these oxides. These oxides can also be doped by applying modification components, as described above for the zeolite catalysts. Treatment with acids, as described above for zeolite catalysts, is also a possible option for modification.

0054Catalysts impregnated with phosphoric acid or boric acid can also be used. Phosphoric acid or boric acid is applied, for example, to SiO₂, Al₂O₃, TiO₂ or pumice, for example by impregnation or spraying. A phosphoric acid-containing catalyst can be obtained, for example, by impregnating H₃PO₄ or NaH₂PO₄ or Na₂HPO₄ solution on SiO₂ and then drying or calcining. However, phosphoric acid can also be sprayed together with silica gel in a spray tower; this is followed by drying and usually calcination. Phosphoric acid can also be sprayed onto the carrier material in an impregnation mill.

0055However, basic catalysts such as MgO, CaO and oxides of lanthanides can also be used for the process according to the invention.

0056The catalysts described here can be used either as 2 to 4 mm strands or as tablets with 3 to 5 mm diameter or as grit with particle sizes of 0.1 to 0.5 mm or as vortex contact.

0057The following examples illustrate the invention:

Manufacture of the catalysts

Catalyst A

0058The borosilicate zeolite of the pentasil type is in a hydrothermal synthesis from 640 g of highly disperse SiO₂, 122 g of H₃BO₃, 8000 g of an aqueous 1,6-hexanediamine solution (mixture 50:50 wt.%) At 170 ° C under autogenous pressure in one Stirred autoclaves manufactured. After filtering off and washing out, the crystalline reaction product is dried at 100 ° C./24 h and calcined at 500 ° C./24 h. This borosilicate zeolite is composed of 94.2 wt.% SiO₂ and 2.3 wt.% B₂O₃.

0059Catalyst A is obtained by shaping the borosilicate zeolite with a shaping aid into 2 mm strands, drying at 100 ° C./16 h and calcining at 500 ° C./24 h.

Catalyst B

0060Catalyst B is prepared by doping catalyst A with Ce (NO₃) ₂, drying at 130 ° C / 2 h and calcining at 540 ° C / 2 h. The Ce content is 1.8% by weight.

Catalyst C

0061Catalyst C was prepared like catalyst B, but soaked with an aqueous solution of Pd and Ce nitrate instead of Ce nitrate. The Pd content is 1.3% by weight, the Ce content 3.6% by weight.

Catalyst D

0062Catalyst D is prepared like catalyst B, but by doping with Cs₂CO₃ instead of Ce nitrate. The Cs content is 0.2% by weight.

Catalyst E

0063Catalyst E is prepared like catalyst B, but by doping with Cs₂CO₃ instead of Ce nitrate. The Cs content is 0.7% by weight.

Catalyst F

0064Catalyst F is prepared like catalyst B, but by doping with Cs₂CO₃ instead of Ce nitrate. The Cs content is 2.3% by weight.

Catalyst G

0065An aluminosilicate zeolite of the pentasil type was made under hydrothermal conditions at autogenous pressure and 150 ° C from 65 g of highly disperse SiO₂, 20.3 g Al₂ (SO₄) ₃ x 18 H₂O in 1 kg with an aqueous 1,6-hexanediamine solution (mixture 50 : 50% by weight) in a stirred autoclave. After filtering off and washing out, the crystalline reaction product was dried at 110 ° C./24 h and calcined at 500 ° C./24 h. This aluminosilicate zeolite contained 91.6 wt.% SiO₂ and 4.6 wt.% Al₂O₃.

0066The catalyst was shaped into 2 mm strands with a shaping aid, dried at 110 ° C./16 h and calcined at 500 ° C./24 h.

Catalyst H

0067The iron silicate zeolite of the pentasil type is dissolved under hydrothermal conditions at autogenous pressure and 165 ° C. from 273 g of water glass, dissolved in 253 g of an aqueous 1,6-hexanediamine solution (mixture 50:50% by weight) and 31 g of iron sulfate synthesized in 21 g of 96% sulfuric acid and 425 g of water in a stirred autoclave for 4 days. The zeolite is filtered off, washed out, dried at 110 ° C./24 h and calcined at 500 ° C./24 h. An iron silicate zeolite with an SiO₂ / Fe₂O₃ ratio of 17.7 and an Na₂O content of 1.2% by weight is obtained. The catalyst is extruded with highly disperse SiO₂ in a weight ratio of 80:20 to 2.5 mm strands, dried at 110 ° C / 16 h and calcined at 500 ° C / 24 h.

Catalyst I

0068Commercially available L-zeolite (Baylith L®) is formed into 2 mm strands using shaping aids. After drying at 110 ° C / 16 h and calcination at 500 ° C / 16 h, the finished catalyst I is available.

Catalyst J.

0069AlPO₄-5 (APO-5) is synthesized by dissolving or suspending 200 g of 98% phosphoric acid and 136 g boehmite in 335 g of water, adding 678 g of a 30% aqueous tetrapropylammonium hydroxide solution and this mixture in a stirred autoclave reacted at 150 ° C in 43 h under autogenous pressure. After filtering off, the crystalline material is dried at 120 ° C. and calcined at 500 ° C. for 16 hours. The AlPO₄-5 thus synthesized contains 45.5% by weight Al₂O₃ and 46.5% by weight P₂O₅. This material is shaped with pseudo boehmite in a mass ratio of 60:40 to 2 mm strands, dried again at 120 ° C and calcined at 500 ° C / 16 h.

Catalyst K

0070AlPO₄-9 (APO-9) is synthesized by dissolving or suspending 200 g of 98% phosphoric acid and 136 g of boehmite in 400 g of water, for this purpose an aqueous solution of 112 g of diazabicyclo-2,2,2-octane (DABCO ) and 320 g of H₂O are added and this mixture is reacted in a stirred autoclave at 200 ° C for 336 h under autogenous pressure. After filtering off, the crystalline material is dried at 120 ° C. and calcined at 500 ° C. for 16 hours. The AlPO₄-9 thus synthesized contains 49.0% by weight of P₂O₅, 37.1% by weight of Al₂O₃. This material is shaped into 3 mm strands using extrusion aids, dried again at 120 ° C. and calcined at 500 ° C./6 hours.

Catalyst I

0071Silicium phosphate-5 (SAPO-5) is made from a mixture of 200 g 98% phosphoric acid, 136 g boehmite, 60 g silica oil (30%), 287 g tripropylamine and 587 g H₂O. This mixture is reacted at 150 ° C for 1168 h under autogenous pressure. After filtration, the crystalline product is dried at 120 ° C. and calcined at 500 ° C. SAPO-5 contains 49.8 wt.% P₂O₅, 33.0 wt.% Al₂O₃, 6.2 wt.% SiO₂. SAPO-5 is formed into 3 mm strands with an extrusion aid, dried at 120 ° C. and calcined at 500 ° C.

Catalyst M

0072BPO₄ is prepared by combining 49 g H₃BO₃ with 117 g H₃PO₄ (75%) in a kneader, evaporating excess water and shaping the reaction product into 3 mm strands. These strands are dried at 100 ° C and calcined at 350 ° C. Catalyst D contains 8.77% by weight B and 28.3% by weight P.

Catalyst N

0073Catalyst N is a precipitated aluminum phosphate, which is obtained by precipitation from Al (NO₃) ₃-H₃PO₄ solution with NH₃ at pH = 6 to 7. After filtering off the precipitate, it is dried at 110 ° C. and calcined at 500 ° C. Catalyst N contains 28.5% by weight of Al and 13.2% by weight of P.

Catalyst O

0074Commercially available zirconium phosphate (CZP 100®) is shaped into 2 mm strands with shaping aids, dried at 100 ° C. and calcined at 500 ° C. for 16 hours.

Catalyst P

0075CePO₄ is obtained by precipitation from 52 g Ce (NO₃) ₃ x 6 H₂O and 56 g NaH₂PO₄ x 2 H₂O. After filtration, the material is shaped into strands, dried at 120 ° C and calcined at 450 ° C. Catalyst P contains 47.1% by weight of Ce and 12.7% by weight of P.

Catalyst Q

0076SiO₂ commercially available under D 11-10®.

Catalyst R

0077100 g SiO₂ strands (D 11-10®), 280 ml 0.1 N HF and 80 ml H₂O are treated under reflux for 1 h. The material is then washed neutral, dried at 110 ° C and calcined at 500 ° C / 5 h.

Catalyst S

0078Al₂O₃ commercially available under D 10-10®.

Catalyst T

0079D 10-10® is impregnated with H₃BO₃, dried at 110 ° C and calcined at 500 ° C / 5 h. The catalyst T is composed of 85% Al₂O₃ and 15% B₂O₃.

Catalyst U

0080Catalyst U is obtained by treating D 10-10® Al₂O₃ with 85% H₃PO₄ for 30 min, then drying at 130 ° C / 2 h and calcining at 540 ° C / 2 h. The P content is 4.9% by weight.

Catalyst V

0081TiO₂ P 25® is shaped into 2 mm strands, dried at 110 ° C and calcined at 500 ° C / 16 h.

Catalyst W

0082200 g of catalyst V are treated with 600 ml of 15% HCl at 80 ° C./1 h. The material is then washed Cl-free, dried at 110 ° C and calcined at 600 ° C / 1 h.

Catalyst X

0083Commercially available niobium oxide hydrate is shaped into 2.5 mm strands with highly disperse SiO₂, dried at 130 ° C / 16 h and calcined at 300 ° C / 4 h.

Catalyst Y

0084Catalyst Y is impregnated with an aqueous palladium nitrite solution. After drying at 130 ° C / 2 h and calcination at 540 ° C / 2 h, the Pd content is 1.5% by weight.

Catalyst Z

0085Catalyst Z is a commercially available Y zeolite that is ion-exchanged with a Pd nitrate solution. The Pd content is 0.5% by weight.

Examples

Examples 1 to 50

0086The reactions in the gas phase were carried out under isothermal conditions in a tubular reactor (spiral, 0.6 cm inner diameter, 90 cm length) for at least 6 hours. The reaction products were separated and characterized by customary methods. The quantitative determination of the reaction products and the starting products was carried out by gas chromatography.

example 1

0087An aqueous piperazine solution (10% by weight of piperazine) is reacted in gaseous form at 400 ° C. and a load of WHSV = 3 h -1 over catalyst A in the apparatus described above. The reaction discharge contains 53.7% by weight of piperazine, 18.4% by weight of DABCO, 4.3% by weight of N-methylpiperazine and 1.3% by weight of N-ethylpiperazine.

Example 2

0088The experiment is carried out as in Example 1, but the reaction is carried out on catalyst G. The reaction discharge contains 23.2% by weight of piperazine, 30.5% by weight of DABCO, 16.2% by weight of N-methylpiperazine, 3.9% by weight of N-ethylpiperazine and 3.5% by weight of methylpiperazine.

Examples 3 to 34

0089The experiment is carried out analogously to Example 1. The results are listed in Table 1 below.<tables id="tabl0001" num="0001"><img file="EP0349859A2_D0001.tif" /></tables><tables id="tabl0002" num="0002"><img file="EP0349859A2_D0002.tif" /></tables><tables id="tabl0003" num="0003"><img file="EP0349859A2_D0003.tif" /></tables>

Example 35

0090A mixture of piperazine and ethanol in a moral ratio of 1: 2 is added in 25% aqueous solution together with 8 l / h N₂ and 4 l / h air at 400 ° C and WHSV = 2.5 h⁻¹ on catalyst Y. The conversion is 91.6%, the selectivity for DABCO 90.2%, for N-methylpiperazine 0.5% and for N-ethylpiperazine 0.4%.

Example 36

0091The procedure is as in Example 35, but catalyst Z is used and the process is carried out at 300.degree. The conversion is 76.9%, the selectivity for DABCO 86.3%, for N-methylpiperazine 2.1% and for N-ethylpiperazine 5.4%.

Example 37

0092Piperazine is evaporated in THF (molar ratio 1: 4) and reacted at 400 ° C and WHSV = 1.5 h⁻¹ on catalyst G. The conversion of the piperazine is 79.5% and the DABCO selectivity is 65.3%.

Example 38

0093Example 38 describes a long-term experiment on catalyst A. The reaction was carried out isothermally at 400 ° C. and WHSV = 1 h -1 in a tubular reactor (inside diameter 2 cm) which was filled with 100 g. A mixture of piperazine / ethanol (1: 1 molar) in 25% aqueous solution and 10 l N₂ / h was used. Regeneration was carried out after the 5th day. The course of the reaction is described in Table 2.<tables id="tabl0004" num="0004"><table frame="all"><title>Table 2</title><tgroup cols="11" colsep="1" rowsep="0"><colspec colnum="1" colname="col1" colwidth="14.31mm" /><colspec colnum="2" colname="col2" colwidth="14.31mm" /><colspec colnum="3" colname="col3" colwidth="14.31mm" /><colspec colnum="4" colname="col4" colwidth="14.31mm" /><colspec colnum="5" colname="col5" colwidth="14.31mm" /><colspec colnum="6" colname="col6" colwidth="14.31mm" /><colspec colnum="7" colname="col7" colwidth="14.31mm" /><colspec colnum="8" colname="col8" colwidth="14.31mm" /><colspec colnum="9" colname="col9" colwidth="14.31mm" /><colspec colnum="10" colname="col10" colwidth="14.31mm" /><colspec colnum="11" colname="col11" colwidth="14.31mm" /><thead valign="top"><row><entry namest="col1" nameend="col11" align="left">DABCO from piperazine / ethanol</entry></row><row><entry namest="col1" nameend="col11" align="left">Long-term tests at 400 ° C, WHSV = approx. 1 h⁻¹, 1: 1 molar,</entry></row></thead><tbody valign="top"><row><entry namest="col1" nameend="col1" /></row></tbody></tgroup><tgroup cols="11" colsep="1" rowsep="0"><colspec colnum="1" colname="col1" colwidth="14.31mm" /><colspec colnum="2" colname="col2" colwidth="14.31mm" /><colspec colnum="3" colname="col3" colwidth="14.31mm" /><colspec colnum="4" colname="col4" colwidth="14.31mm" /><colspec colnum="5" colname="col5" colwidth="14.31mm" /><colspec colnum="6" colname="col6" colwidth="14.31mm" /><colspec colnum="7" colname="col7" colwidth="14.31mm" /><colspec colnum="8" colname="col8" colwidth="14.31mm" /><colspec colnum="9" colname="col9" colwidth="14.31mm" /><colspec colnum="10" colname="col10" colwidth="14.31mm" /><colspec colnum="11" colname="col11" colwidth="14.31mm" /><thead valign="top"><row rowsep="1"><entry namest="col1" nameend="col11" align="left">25th % aqueous solution, 10 l N₂ / h</entry></row><row><entry namest="col1" nameend="col1" align="center">catalyst</entry><entry namest="col2" nameend="col6" align="center">A</entry><entry namest="col7" nameend="col7" align="center">regenerated A</entry><entry namest="col8" nameend="col11" align="center">E</entry></row><row><entry namest="col1" nameend="col1" align="left">running time</entry><entry namest="col2" nameend="col2" align="center">1. Day</entry><entry namest="col3" nameend="col3" align="center">2nd Day</entry><entry namest="col4" nameend="col4" align="center">3rd Day</entry><entry namest="col5" nameend="col5" align="center">4th Day</entry><entry namest="col6" nameend="col6" align="center">5. Day</entry><entry namest="col7" nameend="col7" align="center">1. Day</entry><entry namest="col8" nameend="col8" align="center">1. Day</entry><entry namest="col9" nameend="col9" align="center">2nd Day</entry><entry namest="col10" nameend="col10" align="center">3rd Day</entry><entry namest="col11" nameend="col11" align="center">4th Day</entry></row></thead><tbody valign="top"><row><entry namest="col1" nameend="col1" align="left">DABCO¹⁾</entry><entry namest="col2" nameend="col2" align="char" char=",">34,9</entry><entry namest="col3" nameend="col3" align="char" char=",">29,1</entry><entry namest="col4" nameend="col4" align="char" char=",">28,1</entry><entry namest="col5" nameend="col5" align="char" char=",">25,7</entry><entry namest="col6" nameend="col6" align="char" char=",">25,5</entry><entry namest="col7" nameend="col7" align="char" char=",">35,0</entry><entry namest="col8" nameend="col8" align="char" char=",">40,4</entry><entry namest="col9" nameend="col9" align="char" char=",">31,6</entry><entry namest="col10" nameend="col10" align="char" char=",">28,4</entry><entry namest="col11" nameend="col11" align="char" char=",">28,1</entry></row><row><entry namest="col1" nameend="col1" align="left">Piperazine¹⁾</entry><entry namest="col2" nameend="col2" align="char" char=",">50,8</entry><entry namest="col3" nameend="col3" align="char" char=",">58,4</entry><entry namest="col4" nameend="col4" align="char" char=",">58,3</entry><entry namest="col5" nameend="col5" align="char" char=",">60,3</entry><entry namest="col6" nameend="col6" align="char" char=",">60,6</entry><entry namest="col7" nameend="col7" align="char" char=",">49,0</entry><entry namest="col8" nameend="col8" align="char" char=",">40,1</entry><entry namest="col9" nameend="col9" align="char" char=",">48,2</entry><entry namest="col10" nameend="col10" align="char" char=",">50,0</entry><entry namest="col11" nameend="col11" align="char" char=",">50,4</entry></row><row><entry namest="col1" nameend="col1" align="left">N-methyl-piperazine</entry><entry namest="col2" nameend="col2" align="char" char=",">2,9</entry><entry namest="col3" nameend="col3" align="char" char=",">2,2</entry><entry namest="col4" nameend="col4" align="char" char=",">1,8</entry><entry namest="col5" nameend="col5" align="char" char=",">1,5</entry><entry namest="col6" nameend="col6" align="char" char=",">2,0</entry><entry namest="col7" nameend="col7" align="char" char=",">3,3</entry><entry namest="col8" nameend="col8" align="char" char=",">3,9</entry><entry namest="col9" nameend="col9" align="char" char=",">2,5</entry><entry namest="col10" nameend="col10" align="char" char=",">2,0</entry><entry namest="col11" nameend="col11" align="char" char=",">1,9</entry></row><row rowsep="1"><entry namest="col1" nameend="col1" align="left">N-ethyl</entry><entry namest="col2" nameend="col2" align="char" char=",">3,6</entry><entry namest="col3" nameend="col3" align="char" char=",">3,0</entry><entry namest="col4" nameend="col4" align="char" char=",">2,7</entry><entry namest="col5" nameend="col5" align="char" char=",">2,5</entry><entry namest="col6" nameend="col6" align="char" char=",">2,6</entry><entry namest="col7" nameend="col7" align="char" char=",">3,2</entry><entry namest="col8" nameend="col8" align="char" char=",">4,2</entry><entry namest="col9" nameend="col9" align="char" char=",">3,3</entry><entry namest="col10" nameend="col10" align="char" char=",">3,3</entry><entry namest="col11" nameend="col11" align="char" char=",">2,9</entry></row></tbody></tgroup><tgroup cols="11" colsep="0" rowsep="0"><colspec colnum="1" colname="col1" colwidth="14.31mm" /><colspec colnum="2" colname="col2" colwidth="14.31mm" /><colspec colnum="3" colname="col3" colwidth="14.31mm" /><colspec colnum="4" colname="col4" colwidth="14.31mm" /><colspec colnum="5" colname="col5" colwidth="14.31mm" /><colspec colnum="6" colname="col6" colwidth="14.31mm" /><colspec colnum="7" colname="col7" colwidth="14.31mm" /><colspec colnum="8" colname="col8" colwidth="14.31mm" /><colspec colnum="9" colname="col9" colwidth="14.31mm" /><colspec colnum="10" colname="col10" colwidth="14.31mm" /><colspec colnum="11" colname="col11" colwidth="14.31mm" /><tbody valign="top"><row><entry namest="col1" nameend="col11" align="justify">1) Salary in% in the discharge</entry></row><row><entry namest="col1" nameend="col11" align="justify">2) Catalyst A regenerates after 4 days with air for 4 h at 500 ° C.</entry></row></tbody></tgroup></table></tables><tables id="tabl0005" num="0005"><table frame="all"><title>Table 3</title><tgroup cols="12" colsep="1" rowsep="0"><colspec colnum="1" colname="col1" colwidth="13.12mm" /><colspec colnum="2" colname="col2" colwidth="13.12mm" /><colspec colnum="3" colname="col3" colwidth="13.12mm" /><colspec colnum="4" colname="col4" colwidth="13.12mm" /><colspec colnum="5" colname="col5" colwidth="13.12mm" /><colspec colnum="6" colname="col6" colwidth="13.12mm" /><colspec colnum="7" colname="col7" colwidth="13.12mm" /><colspec colnum="8" colname="col8" colwidth="13.12mm" /><colspec colnum="9" colname="col9" colwidth="13.12mm" /><colspec colnum="10" colname="col10" colwidth="13.12mm" /><colspec colnum="11" colname="col11" colwidth="13.12mm" /><colspec colnum="12" colname="col12" colwidth="13.12mm" /><thead valign="top"><row><entry namest="col1" nameend="col12" align="left">DABCO from piperazine</entry></row><row rowsep="1"><entry namest="col1" nameend="col1" align="left">example</entry><entry namest="col2" nameend="col2" align="center">40</entry><entry namest="col3" nameend="col3" align="center">41</entry><entry namest="col4" nameend="col4" align="center">42</entry><entry namest="col5" nameend="col5" align="center">43</entry><entry namest="col6" nameend="col6" align="center">44</entry><entry namest="col7" nameend="col7" align="center">45</entry><entry namest="col8" nameend="col8" align="center">46</entry><entry namest="col9" nameend="col9" align="center">47</entry><entry namest="col10" nameend="col10" align="center">48</entry><entry namest="col11" nameend="col11" align="center">49</entry><entry namest="col12" nameend="col12" align="center">50</entry></row></thead><tbody valign="top"><row><entry namest="col1" nameend="col1" align="left">catalyst</entry><entry namest="col2" nameend="col2" align="char" char=",">A</entry><entry namest="col3" nameend="col3" align="char" char=",">A</entry><entry namest="col4" nameend="col4" align="char" char=",">E</entry><entry namest="col5" nameend="col5" align="char" char=",">G</entry><entry namest="col6" nameend="col6" align="char" char=",">G</entry><entry namest="col7" nameend="col7" align="char" char=",">A</entry><entry namest="col8" nameend="col8" align="char" char=",">A</entry><entry namest="col9" nameend="col9" align="char" char=",">B</entry><entry namest="col10" nameend="col10" align="char" char=",">E</entry><entry namest="col11" nameend="col11" align="char" char=",">G</entry><entry namest="col12" nameend="col12" align="char" char=",">G</entry></row><row><entry namest="col1" nameend="col1" align="left">Temp., ° C</entry><entry namest="col2" nameend="col2" align="char" char=",">300</entry><entry namest="col3" nameend="col3" align="char" char=",">400</entry><entry namest="col4" nameend="col4" align="char" char=",">400</entry><entry namest="col5" nameend="col5" align="char" char=",">300</entry><entry namest="col6" nameend="col6" align="char" char=",">400</entry><entry namest="col7" nameend="col7" align="char" char=",">300</entry><entry namest="col8" nameend="col8" align="char" char=",">400</entry><entry namest="col9" nameend="col9" align="char" char=",">400</entry><entry namest="col10" nameend="col10" align="char" char=",">400</entry><entry namest="col11" nameend="col11" align="char" char=",">300</entry><entry namest="col12" nameend="col12" align="char" char=",">400</entry></row><row><entry namest="col1" nameend="col1" align="left">WHSV h⁻¹</entry><entry namest="col2" nameend="col2" align="char" char=",">3</entry><entry namest="col3" nameend="col3" align="char" char=",">3</entry><entry namest="col4" nameend="col4" align="char" char=",">3</entry><entry namest="col5" nameend="col5" align="char" char=",">3</entry><entry namest="col6" nameend="col6" align="char" char=",">3</entry><entry namest="col7" nameend="col7" align="char" char=",">3</entry><entry namest="col8" nameend="col8" align="char" char=",">3</entry><entry namest="col9" nameend="col9" align="char" char=",">2</entry><entry namest="col10" nameend="col10" align="char" char=",">3</entry><entry namest="col11" nameend="col11" align="char" char=",">2</entry><entry namest="col12" nameend="col12" align="char" char=",">2</entry></row><row><entry namest="col1" nameend="col1" align="left">aq. Solution%</entry><entry namest="col2" nameend="col2" align="char" char=",">25</entry><entry namest="col3" nameend="col3" align="char" char=",">25</entry><entry namest="col4" nameend="col4" align="char" char=",">25</entry><entry namest="col5" nameend="col5" align="char" char=",">25</entry><entry namest="col6" nameend="col6" align="char" char=",">25</entry><entry namest="col7" nameend="col7" align="char" char=",">25</entry><entry namest="col8" nameend="col8" align="char" char=",">25</entry><entry namest="col9" nameend="col9" align="char" char=",">25</entry><entry namest="col10" nameend="col10" align="char" char=",">25</entry><entry namest="col11" nameend="col11" align="char" char=",">25</entry><entry namest="col12" nameend="col12" align="char" char=",">25</entry></row><row><entry namest="col1" nameend="col1" align="left">Piperazine /</entry><entry namest="col2" nameend="col6" align="center">tert. Butanol</entry><entry namest="col7" nameend="col12" align="center">Diethylene glycol</entry></row><row><entry namest="col1" nameend="col1" align="left">alcohol</entry><entry namest="col2" nameend="col6" align="center">1 : 1 molar</entry><entry namest="col7" nameend="col12" align="center">1 : 1 molar</entry></row><row><entry namest="col1" nameend="col1" align="left">Sales %</entry><entry namest="col2" nameend="col2" align="char" char=",">13,3</entry><entry namest="col3" nameend="col3" align="char" char=",">61,4</entry><entry namest="col4" nameend="col4" align="char" char=",">51,7</entry><entry namest="col5" nameend="col5" align="char" char=",">25,0</entry><entry namest="col6" nameend="col6" align="char" char=",">85,5</entry><entry namest="col7" nameend="col7" align="char" char=",">26,8</entry><entry namest="col8" nameend="col8" align="char" char=",">58,8</entry><entry namest="col9" nameend="col9" align="char" char=",">59,4</entry><entry namest="col10" nameend="col10" align="char" char=",">62,8</entry><entry namest="col11" nameend="col11" align="char" char=",">26,2</entry><entry namest="col12" nameend="col12" align="char" char=",">73,7</entry></row></tbody></tgroup><tgroup cols="12" colsep="1" rowsep="0"><colspec colnum="1" colname="col1" colwidth="13.12mm" /><colspec colnum="2" colname="col2" colwidth="13.12mm" /><colspec colnum="3" colname="col3" colwidth="13.12mm" /><colspec colnum="4" colname="col4" colwidth="13.12mm" /><colspec colnum="5" colname="col5" colwidth="13.12mm" /><colspec colnum="6" colname="col6" colwidth="13.12mm" /><colspec colnum="7" colname="col7" colwidth="13.12mm" /><colspec colnum="8" colname="col8" colwidth="13.12mm" /><colspec colnum="9" colname="col9" colwidth="13.12mm" /><colspec colnum="10" colname="col10" colwidth="13.12mm" /><colspec colnum="11" colname="col11" colwidth="13.12mm" /><colspec colnum="12" colname="col12" colwidth="13.12mm" /><thead valign="top"><row><entry namest="col1" nameend="col1" align="left">Select. %</entry><entry namest="col2" nameend="col2" /><entry namest="col3" nameend="col3" /><entry namest="col4" nameend="col4" /><entry namest="col5" nameend="col5" /><entry namest="col6" nameend="col6" /><entry namest="col7" nameend="col7" /><entry namest="col8" nameend="col8" /><entry namest="col9" nameend="col9" /><entry namest="col10" nameend="col10" /><entry namest="col11" nameend="col11" /><entry namest="col12" nameend="col12" /></row></thead><tbody valign="top"><row><entry namest="col1" nameend="col1" align="left">DABCO</entry><entry namest="col2" nameend="col2" align="char" char=",">78,2</entry><entry namest="col3" nameend="col3" align="char" char=",">78,0</entry><entry namest="col4" nameend="col4" align="char" char=",">88,2</entry><entry namest="col5" nameend="col5" align="char" char=",">84,0</entry><entry namest="col6" nameend="col6" align="char" char=",">70,1</entry><entry namest="col7" nameend="col7" align="char" char=",">45,3</entry><entry namest="col8" nameend="col8" align="char" char=",">56,7</entry><entry namest="col9" nameend="col9" align="char" char=",">66,5</entry><entry namest="col10" nameend="col10" align="char" char=",">62,2</entry><entry namest="col11" nameend="col11" align="char" char=",">46,8</entry><entry namest="col12" nameend="col12" align="char" char=",">51,6</entry></row><row><entry namest="col1" nameend="col1" align="left">N-methylpiperazine</entry><entry namest="col2" nameend="col2" align="char" char=",">-</entry><entry namest="col3" nameend="col3" align="char" char=",">10,2</entry><entry namest="col4" nameend="col4" align="char" char=",">7,1</entry><entry namest="col5" nameend="col5" align="char" char=",">4,0</entry><entry namest="col6" nameend="col6" align="char" char=",">6,9</entry><entry namest="col7" nameend="col7" align="char" char=",">1,1</entry><entry namest="col8" nameend="col8" align="char" char=",">9,2</entry><entry namest="col9" nameend="col9" align="char" char=",">9,5</entry><entry namest="col10" nameend="col10" align="char" char=",">11,5</entry><entry namest="col11" nameend="col11" align="char" char=",">5,3</entry><entry namest="col12" nameend="col12" align="char" char=",">9,3</entry></row><row rowsep="1"><entry namest="col1" nameend="col1" align="left">N-ethyl piperazine</entry><entry namest="col2" nameend="col2" align="char" char=",">-</entry><entry namest="col3" nameend="col3" align="char" char=",">5,2</entry><entry namest="col4" nameend="col4" align="char" char=",">1,3</entry><entry namest="col5" nameend="col5" align="char" char=",">1,2</entry><entry namest="col6" nameend="col6" align="char" char=",">2,1</entry><entry namest="col7" nameend="col7" align="char" char=",">2,2</entry><entry namest="col8" nameend="col8" align="char" char=",">3,2</entry><entry namest="col9" nameend="col9" align="char" char=",">7,3</entry><entry namest="col10" nameend="col10" align="char" char=",">3,8</entry><entry namest="col11" nameend="col11" align="char" char=",">19,8</entry><entry namest="col12" nameend="col12" align="char" char=",">12,8</entry></row></tbody></tgroup></table></tables>