Catalyst and methyl ethyl ketone production process
FIELD: industrial organic synthesis and catalysts.
SUBSTANCE: invention relates to a methyl ethyl ketone production process via catalytic oxidation of n-butenes with oxygen and/or oxygen-containing gas. Catalyst is based on (i) palladium stabilized with complexing ligand and (ii) heteropolyacid and/or its acid salts, in particular molybdo-vanado-phosphoric heteropolyacid having following composition: H11P4Mo18V7O87 and/or acid salt Na1.2H9.3Mo18V7O87, said complexing ligand being notably phthalocyanine ligand. Catalyst is regenerated by making it interact with oxygen and/or oxygen-containing gas at 140-190°C and oxygen pressure 1 to 10 excessive atmospheres. Oxidation of n-butenes is conducted continuously in two-stage mode at 15 to 90°C in presence of above-defined catalyst.
EFFECT: enhanced process efficiency due to increased stability of catalyst resulting in considerably increased productivity and selectivity.
7 cl, 1 dwg, 3 tbl, 8 ex
The invention relates to the field of organic synthesis, namely the method of producing methyl ethyl ketone (MEK=CH3SOS2H5) catalytic oxidation of n-butenes with oxygen, and the catalyst for its implementation.
Due to the exceptionally high dissolving ability of the methyl ethyl ketone (MEK) finds wide industrial application. It is used in the production of polyurethane lacquers, which are used for coating magnetic tapes, computers, tools, audio - and videotapes, is the best deparaffinization lubricating oils, providing them with frost, is a solvent in the production of foams, various paints, epoxy and glyptal resins, PVC skin, artificial skin, serves as the basis of topographic paints and ink for printing.
IEC used as raw materials for the production of methylisobutyl-ketone, 2,3-butandione, methyl ethyl ketone oxime, preventing the formation of films during storage of oil paints. Used for ethylacrylate and isomeric methylcrotonate acids, antioxidants rubbers, for the plasticizing nitrocellulose used in the manufacture of smokeless powders, finds use as a solvent for the film coating of tablets and capsules drugs, as a reagent and solvent in many pharmaceutical manufacturers the Baltic States. Peroxide IEC`and is the initiator of the polymerization of unsaturated polyesters in the manufacture of reinforced plastics.
On an industrial scale IEC receive several ways. One of them is based on liquid-phase free-radical oxidation of n-butane according to the scheme (1). In this way the output of the IEC does not exceed 23%, the main product is acetic acid. Side produce large quantities of waste, which is incinerated.
The advantage of this method is the low cost of raw materials, the disadvantage is the abundance of products, greatly complicating and more expensive process of allocating the IEC.
The main industrial method for the synthesis of the IEC is a three-stage processing butylene fraction, which is a waste product of butadiene for synthetic rubber plants. The method is distinguished by the cheapness of the raw materials; it includes reactions(2)-(4):
Of these reactions (2) and (3) is liquid, and reaction (4) is a heterogeneous catalyst, and in some embodiments is a liquid. The disadvantages of this method are: the abundance of harmful neobespechenii waste contaminated acidic tars sulfuric acid; highly corrosive environment in reactions (2) and (3); high energorekonstrukcija (4); the complexity of the process of separation of the IEC from numerous impurities.
A variation of this method is the process in which instead of H2SO4use acetic acid as an intermediate product is sec-butyl acetate:
The catalyst stages (2A) and (3A) is sulfonation, which quickly becomes clogged with resin and therefore has a limited service life. Used sulfonation is also neobespechenii waste production, seriously impairing its ecology.
Have recently been proposed and other acidic catalysts of these stages, for example vanadium free of heteroalicyclic [Tianxi Cai, Huang He, Lin Jinlong, He Min, Zhang Suofang, Li Luhui // Shiyou Huagong, 1988, V.17, N.9, P.565-567], however, they do not provide a significant improvement in the way. In the second-butylacetate method of obtaining IEC (2A)+(3A)+(4) waste was less than in sulfuric acid. The downside of it was economiccost, due to large capital investments and recurring costs per unit of output due to the corrosive properties of aqueous acetic acid.
In recent years there had been multiple attempts to create new technologies for the IEC of n-butenes. This is evidenced by numerous patents. Of most interest are two new methods: three-stage is, including reactions (5)-(7) with an intermediate receiving gidroperekisi second-butylbenzene [U.S. Pat. USA 5304684, 1994], and the direct oxidation of n-butenes according to reaction (8).
Three-stage method is based on reactions, similar to those used in modern industrial method of production of phenol and acetone through Gidropress cumene. However, obtaining and decomposition gidroperekisi second-butylbenzene stages (6) and (7) runs with less selectivity than receiving and decomposition gidroperekisi cumene. In reactions (6) and (7), along with the IEC and the phenol formed carboxylic acids, their esters, aldehydes, unsaturated ketones, resin. By-products are removed by alkali, which significantly impairs the production ecology. Method (5)-(7) could be promising for the industry, provided a substantial increase in the selectivity stages (6) and (7) receive and decomposition gidroperekisi second-butylbenzene.
In one method of obtaining IEC homogeneous catalytic reaction (8) is similar to the reaction accurascope oxidation of ethylene to acetaldehyde [Jira R., W. Freiesleben // in: Organometallic Reactions / Ed.: E.I.Becker, M.Tsutsui. Vol.3 - New York et al.: Wiley Intersci., 1972 - P.1 - 190]:
Reaction (8) can be carried out in one reactor, feeding it stechiometry the ical mixture of n-C 4H8:O2=2:1, which was previously considered non-explosive [chemist's Handbook. 2nd ed. Additional volume. - L.: Chemistry, 1968 - S]. However, to improve the selectivity and risk reduction reaction should be carried out in two stages: 1) interaction of n-butylene, with a solution of intermediate acting reversible oxidant Oh in the presence of a palladium salt according to equation (9); 2) regeneration of Oh with oxygen according to the equation (10):
As Oh used chlorine copper CuCl2[Jira R., W. Freiesleben, see above], the reduced form of which is ion CuCl2 -- easily oxidized by oxygen. However, the synthesis of IEC according to reaction (9) in the presence of chloride system (PdCl2+CuCl2) was accompanied by the formation of a large number of side of chlorbutanol (25%). In the absence of Cl-ions or when they lack ([Cl-]:[Cu2+]<5) copper not able to serve reversible oxidant. Therefore, for the oxidation of n-butylenes this system proved to be totally unsuitable.
In the invention [SU 700973, B 01 J 23/44, 1994; 822417, B 01 J 23/44, 1994; 1669109, B 01 J 23/44, 1994] was first proposed for use as reversible oxidant (Oh) Mo-V-phosphoric heteroalicyclic patterns of Keggin having the General formula H3+nPVnMo12-nO40marked namechars GPK 1. With their participation butylene reaction described in equation (9a), and the oxygen in equation (10A):
In this way (Oh=CPC1) catalytic system PdII+GPK1) did not contain Cl-ions and therefore provides a complete lack of organochlorine compounds in the reaction products. The selectivity of the system was reached 95÷98%, and the activity in butylene reaction (9a) 100 times the activity of the chloride system (PdCl2+CuCl2). The catalytic system Pd+GPK1) could be successfully used both for oxidation of stoichiometric mixtures of h4H8:O2=2:1 in IEC (one option), and for carrying out reactions (9a) and (10A) in different reactors (two-stage version). The last option was to exclude the contact of oxygen or air with butenes and IEC`Ohm and ensure production safety. However, in the latter case, there was a deep recovery molecules GPK1. This led to significant changes in the chemical composition and properties as ions Pd2+and the molecules of the CCP1. This option is non-stationary catalysis was associated with a decrease in stability of the catalytic system Pd+GPK1).
The stability of the catalyst in respect of ions Pd2+and molecules GPK1 different depended on the number of V atoms in the molecule GPC1(n) and the ratio m:n(m - degree of recovery molecules GPK1). For small values of n(1≤n≤3) and m≈n unstable turned out to be palladium, which stood out on the surface of the recovered solution in the form of a thin mirror film, Pilipovich to the walls of the reactor. When a large number of atoms of vanadium (4<n≤6) and m≈n, in addition to the formation of films of palladium was observed precipitation from solution is also part of the vanadium in the form of a brown solid V3O7·2H2O. After oxidation in air reactor restored form CCP1according to reaction (10A) metallic palladium was dissolved and returned to the solution, but the vanadium precipitate were almost dissolved. Full return of palladium in solution in the process of obtaining IEC did not happen, because part of it was deposited in various parts of the pilot plant. Therefore, the catalyst (Pd+GPK1) could not be regarded as quite stable nor in respect of palladium, either in relation to the CCP1n≥4. The low stability of this catalyst proved to be its greatest disadvantage.
Over the past 30 years there have been many attempts to stabilize the palladium in the catalyst (Pd+GPK1), but for various reasons it was rejected by technology. The simplest method is given in order to reap Pd 2+in solution the introduction of small concentrations of Cl-ions corresponding to the atomic relations Cl-:Pd=5÷50, was proposed in the patent firm Catalytica Inc. (USA) [Application WO 91/13852, 19.09.1991]. However, even with such concentrations of chlorine from a solution of the catalyst quickly passed into the reaction products with the formation of organochlorine compounds. To maintain the stability of palladium in the catalyst had continuously add hydrochloric acid and simultaneously from the reaction products to remove and neutralize chlorine compounds. Therefore mallorey catalyst (PdCl2+ GPK1also has not found industrial application.
The use of palladium in the form of complexes with pyridylcarbonyl acids (α-pikolinos or dipicolinate) increases its stability [SU 1584200, B 01 J 23/44, 1994; 1669109, B 01 J 23/44, 1995]. However, 10 or more times the reduced activity of the catalyst in the reaction (9a), and decreases its performance. This is because the Pd complex derivative of pyridine is too strong, and he overly stabilizes the palladium in higher oxidation degree (Pd2+). Therefore, this method turned out to be-low-tech.
In the invention [U.S. Pat. Japan 07-149685, 1995] catalysts (Pd+GPK1used in mixed solvents containing less than 50% water. As such used di is Xan, ethanol, tetrahydrofuran, γ-butyrolactone or sulfolan. Reaction (8) underwent single-stage: dissolved α-butene at 80°and pressure of O29 kg/cm2oxidized in the IEC. The stability of the palladium ensured by the fact that reaction (9a) and (10A) proceeded simultaneously in one reactor). However, conversion α-butene in the IEC was small: 21% per hour in aqueous dioxane and 14% in aqueous ethanol. In other solvents, it was even less. This method of ethnological and unsafe. The idea of using non-aqueous solvents for the reaction (8) was unpromising, since this reaction proceeds through the stages (9a) and (10A), in which water is acetalization reaction (8), and the decrease of its content dramatically reduces the reaction rate.
This reason allows us to understand low activity in reactions (8) heterogenizing catalysts (Pd+GPK1)deposited on a solid carrier [Stobbe-Kreemers A.W., van der Zon M., Makkee M., J.J.F. Scholten // J. Molec. Cat., A: Chem. - 1996 - V.107 (1-3) - P.247-253]. When using such catalysts were used not liquid water, and water vapor, which could give water only condense in the pores of the support. Therefore, stage (9a), consisting of steps (9a`) and (9a), heterogeneous variant of the reaction (8) was very slow.
A significant drawback of the known methods of synthesis IEC catalysts (Pd+SE is) was the neglect of the influence of corrosion products hardware materials on the performance properties of the catalyst. The omission was attributed to the fact that the same developments as hardware material, it was decided to use titanium, which does not corrode when in contact with a catalyst (Pd+CCP). However, based on technology requirements, it was necessary to contact the catalyst with many parts of the valve that had to be made from special steels.
Our experiment showed that aqueous solutions of Mo-V-phosphoric heteropolyacids (CCP)constituting the catalyst (Pd+CCP), have high corrosion activity against most special steels. Only a few special was enough corrosion-resistant, suitable for equipment in contact with the catalyst (Pd+CCP). However, the products of corrosion (Me=Fe2+(3+), Cr3+, Ni2+) adversely affect the reactivity and stability of the catalyst.
The main and most highly effective pollutant was iron ions Fe3+. The concentrations of [Me]≤0.05 M corrosion products was reduced reactivity and stability of the molecules of the CCP, as well as reduced stability of the complex Pd0·Pc. The lower reactivity of molecules GPK1manifested in the slow on 15÷20% rate of oxygen reaction, and the reduction of resistance in the loss of the oxidized form of the catalyst (at 190°in the process, oxygen is Noah reaction) vanadium precipitation with iron ions. The decrease in resistance of palladium in the presence of Me was manifested in the gradual loss of palladium mobiles from the restored form of the catalyst (at 60÷100°after butylene reaction).
Iron ions in concentrations of 0≤[Fe3+]≤0,06 M caught in the catalyst together with the raw material (V2O5HC) at the stage of its preparation. The corrosion process of special steels increased concentration of Fe3+ions and led to sedimentation. Therefore, the maximum allowable content of corrosion products Me, in which the catalyst (Pd+CCP) must operate sustainably managed to limit the range of 0≤[Me]≤0,1 M In this range of concentrations and Me, the deposition of the oxidized form of the catalyst was able to exclude the introduction into the molecule of the CCP small additives of sodium ions and the increase in the content of phosphorus. The latter measure also improved the stability of the reduced forms of the molecules of the CCP. The result is a new patentable composition (Pd·PC+GPC-7Đ4described below.
A prototype of the proposed method and catalyst to obtain the IEC is the way [SU 1584200, B 01 J 23/44, 1994], in which the catalyst used aqueous solution of palladium salt, a derivative of pyridine and acid salts molybdovanadophosphoric heteroalicyclic (GCA1). The oxidation reaction is conducted the way the interaction of the catalyst with n-butylene, at temperatures of 50-70° From and after the separation of methyl ethyl ketone oxidize the recovered form of the catalyst with oxygen or air at a temperature of 130-160°With (two-stage version). In this way the reaction (8) is in non-stationary conditions of catalysis. The depth and speed of changes of the chemical composition, oxidation and other physico-chemical properties of the catalyst depends on its performance and sustainability at each stage of the reaction (8). Optimization IEC technology requires changes in the composition and properties of the catalyst in the presence of both stages (9a) and (10A) were fast, deep and reversible. However, due to the precipitation stage (9a) the requirement of reciprocity is violated for both palladium and molecules GPK1patterns of Keggin. The deposition of palladium butylene reactor with incomplete return it to the solution in the air reactor instability (palladium) is the lack of a catalytic system Pd+ GPK1). Even more serious disadvantage is the instability of the molecules of the CCP1caused by loss of part of vanadium, falling into the sediment at the stage of (9a) and not returned in the solution at the stage (10A).
The invention solves the problem of increasing the efficiency of the process by increasing the stability of the catalyst components (Pd+CCP), which will ensure its manufacturability and will significantly improve the performance of the catalyst and its activity in both reactions.
The problem is solved by the composition of the catalyst obtain ethyl ketone by oxidation of n-butenes by oxygen and/or oxygen-containing gas, which consists of an aqueous solution of HPC-7Đ4- molybdovanadophosphoric heteroalicyclic or mixture heteroalicyclic and/or its salts and palladium with molar concentration 5 · 10-4÷ 1 · 10-2stabilized phtalocyanines ligand RS at a molar ratio of [Pd]:[Pc]=0,5÷2. Use Mo-V-phosphoric GPK-7Đ4composition H11P4Mo18V7O87or its acid sodium salt composition of Na1,2H9,8P4Mo18V7O87when the concentration of vanadium in aqueous solution of 0.4-2.2 gram-atom per liter.
The task is also solved by a method of producing methyl ethyl ketone MEK by catalytic oxidation of n-butenes using a catalyst which consists of an aqueous solution of HPC-7Đ4-molybdovanadophosphoric heteroalicyclic (7 - number of vanadium atoms in the molecule GPC-7, containing 4 atoms of phosphorus or a mixture of heteroalicyclic and/or its salts and palladium with a concentration of 5·10-4÷1·10-2M, stable phtalocyanines ligand RS at a molar ratio of [Pd]:[RS]=0,5÷2. Use GPK-7Đ4composition H11P4Mo18V7O87or its acid sodium salt composition of Na,2 H9,8P4Mo18V7O87when the concentration of vanadium in aqueous solution of 0.4-2.2 gram-atom per liter.
The method of oxidation of n-butenes in the MEK carried out continuously in two stages, in which the oxidation reaction of n-butenes are in the temperature range of 15÷90°and regeneration of the catalyst is carried out by reacting it with oxygen or oxygen-containing gas in the temperature range 140÷190°when the oxygen pressure 1÷10 ATA.
The main difference of the proposed method of synthesis IEC catalyst (Pd+hPa-7Đ4is that were used heteroalicyclic GPK-7Đ4new members and new methods of stabilization of the catalyst components (different for palladium and vanadium). The new composition of the HPC-7Đ4and new methods of stabilization were found by us in the analysis of the causes system instability (Pd+GPK1in the presence of corrosion products hardware materials, and also on the basis of studies of the kinetics and mechanism of reactions (9a) and (10A).
To eliminate the disadvantages of the known catalysts (Pd+ GPK1and to create a catalyst with high performance and stability of palladium ion was stabilized by complexation with phtalocyanines ligand RS and molecules GPK1magginesu patterns are replaced by molecules GPK-7Đ4not echinostoma composition. The result is a new catalyst (Pd·Pc+GPC-7P4).
The proposed catalysts based on GPC-7Đ4prepared in a manner analogous to known [SU 1782934, 01 25/16, 1992].
Such catalysts have high hydrolytic stability and do not allow precipitation when conducting phases (9a1), (9a2) and (10A) reaction (8) in the conditions of industrial use of the catalyst (Pd·PC+GPC-7Đ4). The activity and performance of the catalysts in a wide range can be adjusted in three ways: a) changes in the concentration of HPC-7Đ4or its acid salts; b) variations of the concentrations of the complex Pd·Pc; 3) regulation of the reaction temperature (9a).
To control the degree of recovery of the catalyst (or oxidation) first used the method of measuring the oxidation potential (E) of the contact solution. Found the value of E (relative to the normal hydrogen electrode) is compared with the curve obtained in advance according to F from m to the catalyst, where m is the degree of recovery molecules GPK-7Đ4(m=[V(IV)]/[HPC-7Đ4]). The value of E to find the current value of m. In the tables of examples, there is a separate graph, where the values E oxidized solutions of catalysts. Them judge how well the regenerated catalyst, as this determines the th performance.
The difference of the catalyst is the high concentration of vanadium (0.4 to 2.2 gram-atom / liter)resulting in increased productivity of the catalyst to ensure its stability.
A further difference of the method of producing ethyl ketone is that regenerate the catalyst by reaction with oxygen or oxygen-containing gas, and improving the performance of the method provides a higher temperature regeneration (up to 190° (C) partial pressure of oxygen (PO2up to 10 ATA.
Another difference is that the reaction is carried out butylene and at lower, than in the method prototype temperatures (from +15° (C)as the catalyst (Pd·Pc+GPC-7P4) has a significantly higher activity than the catalyst of the prototype method, where palladium stabilized dipicolinic acid.
The proposed catalyst (Pd·PC+GPC-7Đ4) has a significantly lower corrosion activity in relation to special steels, which can be made the unit of synthesis of the IEC, as well as significantly less sensitive to the corrosion products of these steels (Me=Fe3+, Cr3+, Ni2+), he does not reduce its stability in the presence of [Me]≤0,1 M
Below is the method of synthesis of catalyst (Pd·PC+GPC-7Đ4), and examples are given which illustrate what s the essence of the invention.
All the catalysts described in examples 1-8, prepared in a known manner [SU 1782934, 01 25/16, 1992]. First synthesize the solution of the CCP or its acid salt of a given composition and a given concentration, based on the stoichiometric quantities of the components of H3P04Moo3and V2O5. Then, the obtained solution is injected sample PdCl2and phthalocyanine.
Example of synthesis 250 ml GPC composition of Na1,2H9,8P4Mo18V7087with a concentration of 0.23 M
The calculation of the amounts of the starting components are according to the equation:
Use 149,04 g of Moo3HC, 36,63 g V2O5HC, 3,66 g Na2CO3, 32,02 ml 7,183-molar solution of N3PO4and 30%H2O2OSC Dissolution of the reagents is carried out in four stages:
1) 149,04 g of Moo3+3,66 g Na2CO3+19,02 ml of N3PO4+1500 ml of N2O+2 ml of N2O2
2) 12,63 g V2O5+700 ml of N2O+50 ml of N2O2+5,0 ml of N3PO4
3) 12.00 g V2O5+700 ml of N2O+50 ml of N2O2+4,0 ml of N3PO4
4) 12.00 g V2O5+700 ml of N2O+50 ml of N2O2+4,0 ml of N3PO4
For dissolution of Moo3in to the technical 3-liter flask is charged with the entire sample of Moo 31.5 liters of distilled water, 3,66 g Na2CO3, 19,02 ml of N3PO4, 2 ml of 30%H2O2HC the mixture boil (it is straw yellow in color) and gradually evaporated to ˜0,8 liter boiling mixture consistently impose solutions obtained, as described below, the dissolution of the V2O5in water in the presence of N2O2and H3PO4. Each subsequent portion of the solution V2O5+H3PO4enter after evaporation of the mixture in the flask to ˜1 L.
For operation 2) - dissolution of V2O5- in 1-liter glass download 12,63 g V2O5, 0.7 l of distilled water and 50 ml of N2About2. The resulting mixture was stirred at +15÷20°With (not above) within 10÷15 minutes to produce a dark red-brown solution. Even before the dissolution of the V2O5to the mixture (with stirring) add 5 ml of N3PO4and expect the termination of allocation of O2formed by the decomposition of peroxide complexes of vanadium. The obtained red-brown (almost black) clear solution was poured into the flask with boiling suspension of Moo3+H3PO4and evaporated to ˜1 L.
Similarly, surgery 3) the dissolution of the V2O5and adding the resulting solution to a suspension of Moo3+V2O5+H3PO4. Atomes is boiled and evaporated to a volume of ˜ 1 l, and then perform the operation 4), coinciding with the operation 3). The combined solution is evaporated to ˜400 ml Dissolution of Moo3control visually: after stopping stirring and standing at the bottom of the bulb should not remain white precipitate of Moo3.
The resulting solution of the CCP filtered through filter paper with a red stripe and the filter is washed with water. If the precipitate on the filter exceeds 2% by weight of the original V2O5it with the filter handle in the Cup 5÷10%N2O2(˜150 ml). The solution is boiled until complete decomposition of H2About2the remains of the filter is separated and the filtrate is added to the combined solution of the CCP with the washing waters. The finished solution is evaporated to 250 ml.
A solution of H11P4Mo18V7O87prepared similarly. In this synthesis are without the addition of Na2CO3according to the equation: 4 H3PO4+18 Moo3+3.5 V2O5→H911P4MO18V7O87+0.5 N2O.
Catalysts for experiments containing CPC, PdCl2and phthalocyanine, usually prepared in 20 ml. for Example, to obtain a catalyst composition [Na1,2H9,8P4Mo18V7O87]=0,23 M, [Pd2+]=6·10-3M with a molar ratio [Pc]:[Pd2+]=1:1 in a solution of 0.23 M CCP injected sample 0,0212 g of PdCl2and 0,096 g phthalo Yanina. The solution is heated and boiled for 8-10 min until complete dissolution hanging. Then the solution is cooled and bring its volume up to 20ml
Example 1. In the reactor-type catalytic duck for 120 ml, fixed on the rocking chair, pour 20 ml of the catalyst composition: [H11P4Mo18V7O87]=0.25 M, [Pd+2]=6·10-3M molar ratio [Pc]:[Pd]=1.5. The reactor thermostatic at 60°C, at atmospheric pressure purge his 10-fold volume of α-butylene composition, %: α-C4H8- 96,3, the sum of CIS - and TRANS-β-C4H8to 1.4, n-butane - 2,2, heavy impurities is 0.1. Connect the reactor burette filled α-butylene, and with vigorous shaking of the reactor to carry out the oxidation of C4H8according to reaction (9). For 32 min a solution of the catalyst oxidizes 325 ml α-butylene (m=5,24) with a selectivity of 98.3%. After Stripping IEC catalyst according to reaction (10) are oxidized in an autoclave with stirrer at 190°and Rho2=4 ATA for 20 minutes Total pressure in the autoclave to 16.4 MPa by the pressure of water vapor, the components of 12.4 MPa. With this catalyst, a further 5 cycles, absorbing each of them from 3.4 to 4.0per mole of the CCPx. The selectivity and activity of the catalyst does not change. Precipitation in solution no.
Examples 2-3 (analog - EN 2230612).
In the first variant of the developed catalyst (Pd· Pc+GPC-7) we stopped on the composition of HPC-7=H10P3Mo18V7O84. The catalyst has good activity indicators in butylene and oxygen reactions (example 2, see table 1), however, studies of the corrosion properties of this catalyst was found that the corrosion products of special steels (Me=Fe3+, Ni2+, Cr3+) significantly reduce its stability and catalytic activity. It is shown that the greatest influence on the catalyst have cations of Fe3+. This effect illustrates the example 3 (table 2).
Example 2. In example 1, characterized in that the catalyst used [H10P3Mo18V7O84]=0.25 M, [Pd+2]=6·10-3M when the molar ratio [Pc]:[Pd]=1.5. The catalyst was tested in 5 cycles (table 1). The selectivity was stable 98-99%. Metal palladium in the process of testing does not appear.
Example 3. In example 2, characterized in that the catalyst used [Fe0.2H9.4P3Mo18V7O84]=0.25 M. the Catalyst was also tested in 5 cycles (table 2). The selectivity was 98-98 .5%, however, in the process of testing the recovered solution was allocated a significant amount of metallic palladium, and the oxidized catalyst gradually allocates the vanadium precipitation. The activity of the SC is Aligator monotonically decreases.
Comparing examples 2 and 3, it can be seen that the introduction of iron cations in a solution of catalyst (Pd+hPa-7) impairs its activity against butylene, as well as its stability in restored, and in the oxidized state.
The lack of stability of the restored form of the catalyst on the basis of H10P3Mo18V7O84managed to eliminate the use of HPC-7 new members - H11P4Mo18V7O87(GPK-7Đ4), in the molecule of which contains four atoms of phosphorus. However, even more effective was the catalyst on the basis of the acid sodium salt of this CCP (see example 4), because the dosed introduction of cation Na+allows you to increase the stability of the vanadium in the oxidized form of the catalyst.
The catalyst (Pd+hPa-7Đ4a new composition, where GPK-7Đ4is the acid salt of H11P4Mo18V7O87meeting the composition of Na1,2H9,8P4Mo18V7O87received additional introduction in a solution of H10P3Mo18V7O84phosphoric acid and sodium cations, different physico-chemical properties from its predecessor, the H10P3Mo18V7O84. The drawing shows curves dependency of the oxidation potential (E) and pH of these concrete is the degree of recovery of the CCP (According to E (curves 1-3) and pH (curves 1` -3`) from m (for a 0.25 M solution of catalysts containing: N10P3Mo18V7O84(1,1`), H11P4Mo18V7O87(2,2`) and Na1,2H9,8P4Mo18V7O87). It is seen that the new catalyst has a significantly higher pH values, so it is less corrosive. Several smaller values of E new catalysts are, however, quite sufficient to provide the desired capacity of the catalyst (3.5-4.0) for 1 cycle. The stability of the new catalyst in the oxidized and reduced state was high: the solution in the research process retains its homogeneity at all stages of the reaction (example 4, table 3).
Example 4. In example 2, characterized in that the catalyst used [Na1,2H9,8P4Mo18V7O87]=0.23 M, the Catalyst was tested in 12 cycles (table 3), and after 10 cycles in the solution is injected cations Fe3+. The selectivity of the catalyst remains stable 98-98 .5%, the solution retains homogeneity. The introduction of iron cations in a solution of catalyst (Pd+hPa-7Đ4) does not impair its activity and stability, i.e., it has become much less sensitive to corrosion products equipment (Me) compared to ka is alization on the basis of H 10P3Mo18V7O84. In this example, the temperature of the regeneration of the catalyst under oxygen pressure decrease from 190°to 180°With several increasing its duration (from 20 min up to 23-25 min). The lower regeneration temperature by 10 degrees considerably simplifies the solution of technological tasks IEC process.
Example 5. In example 4, characterized in that the catalyst used is 0.4 M solution of Na1,2H9,8P4Mo18V7O87when the molar ratio of [RS]:[Pd]=0.5, and for 17 min oxidize 270 ml α-C4H8(m=2,81 e) with a selectivity of 98.5%. After Stripping IEC catalyst oxidized in an autoclave under conditions analogous to example 1. On the second cycle, the activity and selectivity of the catalyst is not changed.
Example 6. In example 1, characterized in that the catalyst used [H11P4Mo18V7O87]=0,2 M, [Pd]=5·10-4when the molar ratio of [Pd]:[RS]=1, for 30 min oxidize 174 ml α-C4H8(m=3,06 e) with a selectivity of 98,7%. After Stripping IEC catalyst oxidized in an autoclave under conditions analogous to example 1. On the second cycle, the activity and selectivity of the catalyst is not changed.
Example 7. In example 4, characterized in that the catalyst using a 0.3 M solution of Na1,2H9,8P4Mo18V7O87PR is a molar ratio of [RS]:[Pd]=2 or [Pd]:[Pc]=0,5), 24 min oxidize 335 ml α-C4H8(m=4,56 e) with a selectivity of 98.2%. After Stripping IEC catalyst oxidized in an autoclave under conditions analogous to example 1. On the second cycle of its activity and selectivity does not change.
Example 8. In example 7, characterized in that the catalyst using a 0.3 M solution of a mixture of Na1,2H9,8P4Mo18V7O87and H11P4Mo18V7O87in the ratio of 1:1, the molar ratio of [RS]:[Pd]=2 or [Pd]:[Pc]=0,5), 24 min oxidize 335 ml α-C4H8(m=4,56 e) with a selectivity of 98.2%. After Stripping IEC catalyst oxidized in an autoclave under conditions analogous to example 1. On the second cycle of its activity and selectivity does not change.
Testing of the catalyst IEC-process stability in 6 cycles. The composition of the catalyst: 0,23 M H10P3Mo18V7O84, [Pd2+]=6·10-3M [PC]=9·10-3M (example 2). Conditions: Vcat=20 ml, tbooth=60°S, treg=190°C, the regeneration time (τ)-20 min (cycle 5 to 15 minutes).
|N Cycle||Eabout(Mabout,)||Vα-buta(ml)/τ (min)||Δm,||Ereset B (mreset,)||EOh(MOh,)||Notes|
|Pdmethand sediment no|
*led regeneration 15 min
|regeneration again led 20 min, Pdmethand sediment no|
The catalyst test Feof 0.2H9,4P3Mo18V7O8 , ([Pd]=6·10-3, [RS]=9·10-3M) (example 3) in 5 cycles of oxidation α-C4H8in the IEC. Conditions: amount of catalyst=20 ml; tbooth=60°S, tKIS=190°C.
|No. of cycle||EaboutIn||Time butylene reaction, min||The amount of absorbed butylene, ml (m, e-)||The average speed of the bout. the reaction for 10 min, ml/min||EresetIn||Time oxygen reaction, min||EOhIn||Notes|
|23,2||0,518||20||0,906||Prior experience in solution was a small jelly-like precipitate. "Duck" and agitator Pd plaque is not visible.|
|20,6||0,521||20||0,959||In the solution to experience a small residue|
|23,9||0,520||20||0,917||In the solution to experience there is a small light precipitate. "Duck" - metal.|
|16,3||0,519||20||0,963||In the solution to experience there is a small light precipitate. To "duck" a lot of metal. When the oxidation is not all Pd with a stirrer was dissolved|
Testing of the catalyst IEC-process stability in 12 cycles. The composition of the catalyst: 0,23 M Na1,2H9,8P4Mo18V7O87, [Pd2+]=6·10-3M [Pc]=9·10-3M (example 4).
Conditions: Vcat=20 ml, tbooth=60°C, treg=180°C. the Loops 11 and 12 are carried out with the addition of cation Fe3+(0.2 mol per 1 mol of Na1,2H9.8P4Mo18V7O87).
|Eabout(Mabout,)||Vα-buta(ml) /τbooth(min)||Δ m,||EresetB(mreset,)||τreg, min||EOh(Mox,)||Notes|
|1||kgs 1,090td align="center">
|20||0.962 (2.25)||Pdmethand sediment no|
|The solution recovered quite deep: met. Pd no.|
|To the solution was added cations Fe3+the composition of the CCP: Feof 0.2Na1,2H9,2P4Mo18V7O87|
|The homogeneous solution|
The results obtained in this series of studies of a new catalyst (Pd+hPa-7P4) on the stability, allow us to make several important conclusions. Chief among them is that the regeneration of the catalyst can be carried out at 180°if ˜15-20% increase in time oxygen reaction compared to her time at 190°With (20 min). From table 3 it can be seen that a 20-minute oxidation catalyst at 180°does not provide the required end-degrees for restoring the Oia (m Oh˜1.6-1.5), because oxidized during this time the catalyst has mox˜2.25-2.30. Nedookislennye catalyst will result in a decrease of its capacity in the next cycle, as required by criterion of the high stability of the catalyst must be compliance with the working intervals of values of m, primarily in the recovered solution (mreset≤˜5.6). This restriction of the values of m above will ensure high stability of palladium in the solution of the catalyst and regeneration of the catalyst at 180°C for 25 min will ensure its capacity not less than 4the passage (see 5-12 cycles in table 3).
The results also show that the introduction into the solution of the catalyst corrosion products Me (cations Fe2+) practically does not change the stability and activity of the catalyst (see 11 and 12 cycles, table 3). Some decrease of the oxidation potential of the solution by adding cations of iron (11 cycle, the value of Eaboutwith the introduction of Fe2+reduced from 1.036 to 1.029) practically does not change the working range Δm changes m when the catalyst.
1. The catalyst obtain ethyl ketone by catalytic oxidation of n-butenes by oxygen and/or oxygen-containing gas on the basis of the e palladium, stable complexing ligand, and heteroalicyclic and/or its acid salts, characterized in that as heteroalicyclic the catalyst contains GPK-7Đ4molybdovanadophosphoric heteroalicyclic composition of H11P4Mo18V7O87and/or its acid salt composition of Na1.2H9.8P4Mo18V7About87and as a complexing ligand - phthalocyaninate ligand RS.
2. The catalyst according to claim 1, characterized in that the concentration of vanadium in aqueous solution GPK-R or its acid salt is 0.4-2.2 gram-atom per liter.
3. The catalyst according to claims 1 and 2, characterized in that the palladium concentration 5·10-4÷1·10-2M is stable in solution phtalocyanines ligand RS at a molar ratio of [Pd]:[Pc]=0,5÷2.
4. The method of producing ethyl ketone by catalytic oxidation of n-butenes by oxygen and/or oxygen-containing gas using a catalyst based on palladium complexes of its ligand and heteroalicyclic and/or its acid salt with subsequent regeneration of the catalyst by its interaction with oxygen or oxygen-containing gas, characterized in that the use of the catalyst according to any one of claims 1 to 3.
5. The method according to claim 4, characterized in that the oxidation reaction of n-butenes is carried out at a temperature of 15÷90°C.
Cab according to claim 4, characterized in that the regeneration of the catalyst is carried out by reacting it with oxygen or oxygen-containing gas at a temperature of 140÷190°C.
7. The method according to claim 6, characterized in that at the stage of regeneration of the catalyst partial pressure of oxygen equal to 1-10 ATA.
FIELD: industrial organic synthesis.
SUBSTANCE: polyetherpolyols are synthesized via reaction of diols or polyols with ethylene oxide, propylene oxide, butylene oxide, or mixtures thereof in presence of suspended multimetallic cyanide complex catalyst in reactor provided with stirrer, wherein reaction mixture is recycled with the aid of pump through externally located heat-exchanger.
EFFECT: increased productivity based on unit volume in unit at high quality of product.
9 cl, 4 ex
FIELD: organic synthesis catalysts.
SUBSTANCE: invention relates to improved method of preparing double metal cyanide catalysts for synthesis of polyether-polyols via polyaddition alkylene oxides to starting compounds possessing active hydrogen atoms. Method comprises following steps: (i) mixing one or several solutions of water-soluble salts of Zn(II), Fe(II), Ni(II), Mn(II), Co(II), Sn(II), Pb(II), Fe(III), Mo(IV), Mo(VI), Al(III), V(V), V(IV), Sr(II), W(VI), Cu(II), or Cr(III) with solution of water-soluble cyanide ions-containing salt or acid of Fe(II), Fe(III), Co(II), Co(III), Cr(II), Cr(III), Mn(II), Mn(III), Ir(III), Ni(II), Rh(III), Ru(II), V(IV), or V(V) with the aid of mixing nozzle, preferably jet disperser; (ii) isolation of catalyst from resulting dispersion; (iii) washing; and (iv) drying.
EFFECT: increased catalytic activity, reduced particle size, and narrowed size distribution of particles in polyether-polyols production process.
8 cl, 5 dwg, 9 ex
FIELD: polymerization catalysts.
SUBSTANCE: invention disclose a method for preparing catalyst based on DMC (4,4'-dichloro-α-methylbenzhydrol) appropriate to be used in polymerization of alkylene oxides into polyol-polyethers comprising following stages: (i) combining aqueous solution of metal salt with metal cyanide aqueous solution and allowing these solutions to interact, while at least one part of this reaction proceeds in presence of organic complexing agent to form dispersion of solid DMC-based complex in aqueous medium; (ii) combining dispersion obtained in stage (i) with essentially water-insoluble liquid capable of extracting solid DMC-based complex and thereby forming biphasic system consisting of first aqueous layer and a layer containing DMC-based complex and liquid added; (iii) removing first aqueous layer; and (iv) removing DMC-based complex from layer containing DMC-based catalyst.
EFFECT: lack of negative effect on DMC-based catalyst activity.
16 cl, 1 tbl, 3 ex
FIELD: polymerization catalysts.
SUBSTANCE: catalyst is composed of double metal cyanide compound, organic ligand, and two complexing components other than precedent organic ligand and selected from group including: polyethers and polyesters, glycidyl ethers, esters from carboxylic acids and polyatomic alcohols, bile acids, bile acid salts, bile acid esters, bile acid amides, and phosphorus compounds, provided that selected complexing components belong to different classes.
EFFECT: substantially increased catalytic activity.
5 cl, 1 tbl, 16 ex
FIELD: polymerization catalysts.
SUBSTANCE: invention provides double metal cyanide catalysts for production of polyetherpolyols via polyaddition of alkylene oxides to starting compounds containing active hydrogen atoms, which catalysts contain double metal cyanide compounds, organic complex ligands, and α,β-unsaturated carboxylic acid esters other than above-mentioned ligands.
EFFECT: considerably increased catalytic activity.
6 cl, 16 ex
FIELD: textile, paper and chemical industries; protection of environment in production of bleachers, biocides and components of oxidizing processes.
SUBSTANCE: proposed catalyst contains one or more metals of platinum group used as active component, one or more polyolefines and activated carbon carrier. It is preferably, that polyolefines have molecular mass above 400 and are selected from ethylene homopolymers and ethylene copolymers with alpha-olefines, propylene homopolymers and propylene copolymers with alpha olefines, butadiene homopolymers and copolymers with styrene and other olefines, isoprene homopolymers and copolymers with other olefines, ethylene-propylene copolymers, ethylene-propylene diolefine three-component copolymers, thermoplastic elastomers obtained from butadiene and/or isoprene and styrene block-copolymers, both hydrogenized and non-hydrogenized. Hydrogen peroxide is produced in presence of said catalyst from hydrogen and oxygen in reaction solvent containing halogenated and/or acid promoter. Proposed catalyst makes it possible to increase degree of conversion and selectivity of process, to obtain aqueous H2O2 solutions at content of acids and/or salts at level of trace amount.
EFFECT: enhanced efficiency.
48 cl, 1 tbl,18 ex