Procedure for the oxidation from Olefinen to insatiated aldehydes

The invention bet1 ifft a procedure for the oxidation of Kohlenwasserstoffcn by means of oxygen, in particular from insatiated hydrocarbons in presence of a catalyst, which contains the oxides of molybdenum and tellurium. Even if the invention olefirte itself on the oxidation of the most diverse connections such as Oleßne, Dis, acetyl niche, aromatic or alkylated aromatic carbon compounds, alcohols, aldehydes, Terpene etc. to use lets, is it completely particularly interesting for the production of nngesättigten aldehydes from Olefinen. A very important practical application of the invention is the production of Acrolein from propylene or of Methacrolein from rsobutyIen. There is well-known already different catalysts for the execution of such reactions, however it was not so far possible, really interesting yields at aldehydes to obtain related to the used up Olefin. In the most favorable case the yield hardly goes beyond 85%. Thus the best conditions lead in a bckannten procedure, which uses the oxide of hexavalent tellurium as well as oxides of metals such as molybdenum, tungsten, etc., i.e. the atomic ratio Te/Mo = 1/6, to Acroleinausbeuten the propylene, with a transformation degree of 76 to x5, used up from 50 to 85%, related to, 37%. The transformation degree falls with rising yield. The erfindungsgemäfle procedure permits it however, increased aldehyde to hiving to obtain, i.e. 95% or more, related to the weight of the converted Olefins, wobd the transformation degree of the propylene 55% to exceed can and also the reaction temperature lower sdn can than in similar well-known catalytic procedures. Thus the procedure according to invention between 300 and 500° C can be through-felt; the preferential temperature range amounts to 380--440 ° C, while one is compelling with the well-known molybdenum tellurium catalysts to work over 450 ° C. The procedure according to invention for the oxidation from Okfmen to insatiated aldehydes, in particular from propylene to Acrolein, in presence of a catalyst, which contains the oxides of molybdenum and tellurium, consists of it, dafi one a gaseous mixture of Kohlenwass “rstoff, sow rstoffund nitrogen with a temperature from 300 to 500 ° C with a catalyst in contact brings, the 10 to 40 mol MO3 and 2--50 mol of TeOa on i mol of P2 0 contains, whereby the mol number of MOa 0,8--6 per mol TeOs and M for molybdenum amounts to stands, which can be if necessary partly replaced by tungsten and/or vanadium. 0 according to invention used the catalyst therefore mol molybdenum, tungsten WAD consists/or vanadium oxide, preferably 1 mol of P2 05 to 10 of at least 1 mol of P2 05 auf40--24 mol of these oxides. The TeO3 - Content according to invention used katalydschcn of the system can vary M the associated metal between rather far borders, for example designation by 1 mol of TeOz to 8 mol of MO3, wobd, up to 1 mol of TeOa auf0,5 mol of MON. The preferential mol Verhälmis MO3 /TeOs is 0.8 to 6 or better 1--3. With other words uses the preferential would drive out, ngsform the invention catalyst systems of the composition P Oö-kmMO3 +nTeO3, where mine-worth of 10 to 24 and n from 2 to 50 or better 8--and n and m the mol numbers have 25 are. No. 261566 if one also accurately to say cannot become, whether the oxides of the catalyst represent a chemical compound or a physical mixture after calcining, some particularly favourable connections in the following descriptive, as if it concerns genuine oxide connections. In particular excellent of results with catalysts of the composition P2 05,24 MOO 4 TeO to P O5,24 MoOa.24 TeO3 and P205.24 MOO8,4, are preferably received to 8 TeOa to P2 Oö.24 MOO 22 TeOs whereby these oxides are uniert on a carrier of well-known type such as alumina, silicon oxide, Alumosilicat od. such. The portion of this carrier in the ferggen catalyst amounts to preferably s0 10--70 Gew. - % Trockensuhstanz” whereby excellent of results with one carrier portion of 30 to 60% to be obtained. The molybdenum can be partly or replaced completely by vanadium and/or tungsten. The catalysts used with the ertindungsgemäßen procedure are manufactured, by manufacturing first an aqueous solution of all or a part of the elements, in particular from tellurium, which can be used, molybdenum and phosphorus, which are used in form of their water-soluble connection; those is mixed with a Kieselsäuresol or if necessary with the SoI of another material” that than carriers to serve is to assume, woranfman this mixture gel form lets. The received gel becomes, after it into an appropriate physical form, e.g. Grain, Pastillen od. such brought is getroeknet and afterwards calcined, before it is used in the intended reactions. Burning can take place at temperatures from 350 to 700 ° C, iedoch at one temperature is preferably accomplished, the something, for example 20--80 ° C” above the temperature preserves, at which the catalyst is used for the oxidation by propylene. Preferential temperatures lie thus between approximately 400--500 ° C, preferably 420--480 ° C. After an amended execution form of the procedure for the production of the catalyst the aqueous solution of the connection is acidified molybdenum and phosphorus by tellurium, preferably by addition of an acid such as HNOs, which escapes in the process of burning completely. By acidifying it is possible with large security to hold the components in solution” the danger to thus exclude that one of them fails. Furthermore after following Gelbildung is accelerated after the mixture with the Sol. If necessary the components can be dissolved directly in the silicic acid Hydrosol. The soluble components, which can be used for the production of the initial solution erfiudungsgemäß of the used catalyst, are for example Tellurate, Molybdate, phosphates, Molybdatotellurate, Molybdatophosphate, Phosphato tellurate, vanadates, Wolframate, Molybdato vanadates and Molybdato phosphato vanadates of Alkn] imetallen or ammonium, or the appropriate acids. One used thus after the preferential execution form of the invention the connections of Tel, 5 lur, molybdenum, phosphorus etc. not in solid state, how it is usual with the production of the well-known catalysts, in order it with the Kieselsäuresol to dry, but in solution; with other words only liquid substances are present in the first manufacture stage after the invention, which are solved in water completely; only on the product, which was formed by VerfesUgung of this liquid, homogeneous phase, one uses the drying process and D nn calcining. In this way received catalyst has another structure than the well-known tellurium catalysts after the Kalziniertmg. It possesses a very large homogeneity, which is to due to the extremely regular distribution of the Allativen Elemmte over the carrier. Its structure and homogeneity permit the Oxydaüon with excellent yield and good Seleküvität at sufficiently low temperatures, in order to let the catalyst remain stable. Ertiudungsgemäß used catalyst shows improved 4 mechanical characteristics and is suitable well for the flow praying technology (fluidization). With the ertiudungsgemäßen use of the catalyst for the oxidation from propylene to Acrolein the duration of the Kontalctes of the hydrocarbon Sauerstoffmi can be varied chung with the catalytic mass according to desire, however it lies preferably in the Gröflenordnung of 00 5 to 15 seconds and better 1--5 seconds at temperatures from 380 to 440 o C. so with these Acroleinerzeugung can the mixture from propylene and air so much air enthaken that the oxygen in surplus is present over. In particular one can with an oxygen surplus of for example 10--109 o work. For a surplus up to approximately 50% however that is to be adjusted steam content of the mixture accordingly, in order to exclude a danger of explosion; the explosive condition can be avoided also in every other well-known way” in particular by use of a device, which uses the catalyst in form of a fluidized bed (Fluidisaüon), in which an explosion is not to befiirchten. preferably the oxygen is used in a surplus from 20 to 40% over the theoretically necessary quantity. It is however mögäch to work with a stoichiometric mixture from propylene and oxygen to or also with a surplus of propylene; . Use of over chüssigem Propy the o is it len for economic reasons the best, if this Uberschuß does not exceed 20% hydrocarbon. The invention is more near described in the following on the basis of remark examples. With spi el 1: Procedures admitted production of the catalyst after one from franz. the patent specification No. 1.345.016. One mixes 22.4 g fine, dry crystalline AmmoniumtelluromoIybdatpulver (NH4) “TeMo “O 4. .7H2 0 and 72 g of a Kieselsäuresols with 6% S102. In such a way formed mash is dried with 110 ° C and calcined then 24 h with 420 ° C. The received product consists of 80 Gew. - % TeO3 .6MoO3 and 20% SiO2. The product is gesiebt. The grains of approximately 1 mm size are used as catalyst. The catalyst is then examined in a pipe from rustproof steel by 12 mm in diameter for its effect. One inserts into the pipe 10 ml the catalyst mass and holds it then in a salt bath 415 ° C. By the pipe one lets a Gasmischtmg flow out of 71 space parts of air (according to 17.7 Ranurteilen oxygen), to 15 Ranmteilen propylene and 14 space parts of Wasserdarnpf. The gas throughput amounts to 11.2 1 per hour, related to the gas volume with 0 ° C under 760 mm Hg printing. This corresponds to a time of contact computed by 1.25 seconds between the gas and the catalyst, for the filled pipe, whereby the Gasa5 volume on Normalbedingtmgen is zttrückgefülart. The transformation degree of the propylene amounts to 30% and the selectivity for Acrolein 76%. Example 2: The same catalyst as in example 1 under the same conditions examined with the change that the temperature of the Reaktionsrohres is held 460 ° C. The propylene transformation is then 37% and the Acroleinselektivität 80%. Example 3: After the invention manufactured catalyst. One mixes 22.4 g Ammoniumtelluromolybdat (NH4) “TeMo “O24,7 H2 0 and 560 g of a Kieselsäuresols with 6% SiO2. The mixture is acidified with HNO3, poured several times strongly agitated, until the Telluromolybdat separated completely, and then on a glass plate. If the product accepted consistency in the form of paste, it is pressed by a filter sheet metal from rustproof steel, whose holes have 1 mm in diameter. In such a way received product is dried 24 h in a furnace with 110 C and calcined then further 24 h with 450 ° C. In such a way formed catalyst contains 34.4 Gew. - % TeO3,6 MoO3 and 65.6% SiO2; it is examined with 415 ° C in the way described in example 1. The propylene transformation degree amounts to 36.4% and the Acroleha with a yield (selectivity) of 82,5% is formed, related to the used up propylene. The activity of the catalyst is thus better than those of the well-known catalyst of the examples 1 and 2, since it makes the achievement possible of similar results with 415 o C as the well-known catalyst at a temperature of 460 ° C. Example 4: To the output mixture of example one gives 1.1 g 75%ige phosphoric acid to 3 according to 0.824 g H3 PO4, while one proceeds in all other respects directly. The received catalyst contains 35% P905.24 MOO3 of,4 TeO3 and 65% SiO” it results in the case of 415 ° C a propylene transformation of 38% and a Acroleinselektivität of 84%, which means a certain improvement in relation to example 3. Example 5: The catalyst of example 4 results in a transformation of 40% and a selectivity of 87% in the case of 460 o C. Example 6: The production of the catalyst takes place in the way, which admits 1.345.016 franz. of the Pateutschrift from No. is, thus as however in the examples 1 and 2, under addition from 1, I g 75%iger phosphoric acid. One receives so a catalyst of the 83.6% P, O5.24 MoO8,4 TeO3 and 16.4% SiO2 contains. The reaction with 415 ° C results in a propylene transformation of 37% and a Acroleinselektivität of 82%. The comparison with example i shows an improvement, which is to be attached to the addition of PzO. Example 7: A catalyst is manufactured in the procedure by example 3, soaked however from 30,3 g Molybdatophosphorsäure, 24 MoO3 .2PO4 H3,48 H2 0 and 215 g of a Kieselsäuresols with 6% SiO2 after the drying process and calcining the mass with a tellurium acid solution in such a quantity that the atomic ratio is Mo/Te equal to 5. The soaked product is dried 5 h with I10 ° C and calcined then 12 h with 450 Q C. One receives finally a catalytic mass, the 70 Gew. - % P, O5.24 MoO3,4, 8 TeO and 30 Gew. - % SiO2 contains. The catalytic activity of this system is determined in the same way as in example i with 388 ° C. The received transformation degree is 34% and the Acroleänausbeute, related to which propylene used 88% (selectivity). Example 8: The catalyst of example 7 is used for the oxidation by propylene with 414° C. The Umwandlnng amounts to 50% and the Acroleinselektivität 88%. Example 9: During the production of the catalyst after example 7 one uses the same materials in the same quantitative proportions, solves however the Molybdatophosphorsäure and the tellurium acid first together in cold water up to the saturation, without additive of nitric acid. In such a way received solution is mixed with the Kieselsäuresol. If the mixture were converted into a gel, one proceeds “far as in example 3. In the case of 414 ° C this catalyst results in a transformation of 48,5% and a selectivity of 90%. Example 10: For the output mixture of example 3 one gives 0.66 g 75%ige phosphoric acid = to 0.495 g H3PO and 0.77 g tellurium acid. In all other respects one proceeds as in example 3. one receives a catalyst, whose active portion has the composition lo 0.6 P2 05,24 MOO8,4, 8 TeO3. This catalyst leads with 414 82.8%; it is thus less aküv than that of the examples 8 and 9, from which it see by its P CO-content of 0,6 instead of 1 mol differentiates. Example 11: During the production after example one gives so much phosphoric acid to 7 in addition that one receives 17 a catalyst, whose active portion has the composition 2 P2 05,24 MoO3,4, 8 TeO3. This catalyst results in a propylene transformation of 50% and an aero flax selectivity of 92% in the case of 414 o C. Example 12: In the procedure of example 3 one prepares a catalyst from a mixture of 21 g Molybdatophosphorsäure, for 9 g Telktrsäure and 250 g Kieselsäurehydrosol with 6% SiO2. After the drying process and calcining one receives a katalydsche mass, those to about 65 Gew. - % P205.24 MoO3,8, 2 TeO3 and 44% SiO2 contains. The oxidation of propylene with 414 o C results in a propylene transformation of 51,4% and a Acroleinselekdvit'ät of 93%. Example 13: One proceeds as in example 12, however so much phosphoric acid gives in addition that one receives the following catalyst composition. 2 P2 05,24 MoO3,8, 2 TeO3. This catalyst leads to a propylene transformation of 52% and a Acroleinselektivität of 93,7%. Example 14: In the procedure of example 3 one makes a catalyst of a mixture of 21 g Molybdatophosphorsäure, 14 g Telktrsäure and 250 g Kieselsäuresolmit 6% SiO. After the drying process and calcining the catalytic mass contains 65 Gew. - % P205.24 MoO3,12, 7 TeO3 and 35% SiO2. The production of Acrolein with 404 o C under the conditions of example 1 leads to a propylene transformation degree the propylene converted of 53,3% and a Acroleinausbeute of 95% (Selekfivität), related to. Example 15: To the initial solution of example one gives so much H3 PO to 14 in addition that the molecular portion of P2 05 in the catalyst is doubled. The transformation is then 54% and the selectivity 95.6%. Example 16: In the procedure of example 9 one makes a catalyst of a mixture of 17,5 g Ammoniumphosphorvanadomolybdat with a Mo] V-relationship of 0,875, 17.5 g tellurium acid and 250 g Kieselsäuresol with 6% SiO2. The composition of the almven part of the catalyst is 1.14 P2 05,24 MoO3,22 TeOs. 1.72 V2 05. With 400 ° C the transformation code under the values of feeding rate and gas composition 55%, while the aero flax with a selectivity of 91% forms, indicated in example 1, is related to the used up propylene. The results of the managing examples are summarized in the following table. In this the individual columns mean: I never the example. [...] mol number of PaO5 to 24 mol of MoO3 in the catalyst. [...] mol number of TeO3 to 24 mol of MoO3 in the catalyst. IV Oxy tafionstemperam_r the propylene. V proportional propylene transformation. VI proportional Acroleinselekfivität. s VII for the catalyst production used procedure. S well-known procedure by mixing the firm reactive components with a Sol and anschLießmde drying process and calcining. T Erfiudungsgemäßes procedure, preceding preparing of an aqueous solution, which contains the reactive components and the Kieselsäuresol, transformation of this solution in a gel, a anschießende drying process and a calcining. A modification of the procedure T by work in sour environment. L table MoO3 = 24 mol of IF i i example [...] III IV V VI VII No. PzO5 TeO3 o C transformation Selektivhät % procedure is 1 2 3 4 6 7 8 9 11 12 13 14 16 0 0 0 1 1 1 1 1 1 o, 6 2 1 2 1 2 1.14 {4 4 4 4 4 4 4.8,4.8,4.8,4.8,4.8,8.2,8.2 12.7 12.7 22 + 1.72 V, O5 415,460,415,415,460,415,388,414,414,414,414,414,414,404,404 4O0 37 36.4 38 37 34 48.5 42 51.4 52 53.3 54