FR2510992A1 - Catalyst for (amm)oxidation of olefin - contains molybdenum, cobalt, nickel, iron, bismuth, titanium, aluminium, oxygen and alkali metal - Google Patents

Abstract

A catalyst for the (amm)oxidation of olefins comprising a compsn. of the formula MoaCobNicFed BicX6TigAlhYiOj (I) (where Y is an alkali metal and a-j express the atomic ratio of the corresp. elements and when a is 10, b is 0-10, c is 0-10, b+c is 1-10, d is 0.1-7, e is 0.01-3, b is 0.01-1, g is 1-15, h is 0-10, i is 0-4 and j is a number satisfying the average valency of the elements and is 33.2-104.5) is prepd. by heating a suspension or soln. of cpds. contg. the elements in (I) in amts. to satisfy (I) to concentrate or dry the suspension or soln., incorporating to the paste or powder obtd. a soln. of a polyvinyl cpd. and/or a N-contg. cpd. in an organic solvent, the cpd. being in an amt. of 1-10 (2-8) wt.% w.r.t. the solids of the paste or powder, shaping the mixt. into an article and calcining the articles pref. in a gaseous atmos. contg. oxygen at 400-700 (450-460)deg.C for 3-20 (5-10) hrs. The catalyst has a good aptitude for shaping and perform with improved reproducibility. When used for producing unsatd. nitriles or aldehydes, these are obtd. at relatively low temps. in high yields. The catalyst also has high mechanical strength and therefore does not pulverise when used in a fixed bed reactor or during transport.

Description

 The present invention relates to a process for preparing a catalyst for oxidation and ammoxidation of olefins and a process for separating unsaturated nitriles using this catalyst.

 More particularly, the invention relates to a process for preparing a catalyst which is used for the catalytic oxidation of olefins, such as propylene and isobutylene, to produce unsaturated aldehydes, such as acrolein and methacrolein. or for the catalytic ammoxidation of such olefins to produce unsaturated nitriles, such as acrylonitrile and methacrylonitrile, in the high temperature vapor phase and which comprises the elements represented by the formula Mo-Co / Ni-Fe-Bi- V / Te-Ti (Ai) - (Y) (Y is an alkali metal). The catalyst prepared according to the process of the invention is characterized by increased mechanical strengths and the ability to provide the desired unsaturated aldehydes or nitriles in high yield and a high spatio-temporal yield. The invention also relates to a process for ammoxidation of olefins to unsaturated nitriles using this catalyst.

 Various catalysts have heretofore been proposed for the catalytic oxidation of olefins to produce unsaturated aldehydes or for the catalytic ammoxidation of olefins to produce high temperature unsaturated nitriles in the vapor phase. Various methods have also been proposed for preparing such oxidation and oxidation catalysts.

 As catalysts useful in the catalytic oxidation or ammoxidation of olefins, those which meet the following requirements are difficult or even impossible to prepare and are currently highly desired.

(1) The mechanical strength is high. (2) The optimum temperature of the oxidation or ammoxidation reaction which has a great influence on the service life and usefulness of the catalyst is low. The desired unsaturated aldehydes or nitriles (3) can be produced in high time-domain yield, (4) in high yield, and (5) in good reproducibility.

The Applicant has proposed catalysts of Mo-Co / Ni-Fe-Bi-V / Te-Ti-O type in the patent application.
FR 79 22416 and of Mo-Co / Ni-Fe-Bi-Al-Ti-type (A) -O (A is an alkali metal) in the patent application FR 79 31762.

These proposed catalysts meet the above requirements to a very large extent.

 In the above-mentioned FR patent applications, it is stated that the catalysts are prepared by a process in which compounds containing the constituent elements of the catalyst are mixed together; the mixed suspension or solution obtained is heated to dry; and pulverized, shaped into tablets and then calcined the solid obtained. However, the catalysts prepared by this process have the following problems. First, the pulverized product has poor tableting ability. Then, the catalysts tend to exhibit poor reproducibility, that is, the desired unsaturated aldehydes or nitriles are not always produced with a consistently high yield. To a certain extent, the first problem cited can be solved by incorporating organic additives. such as cellulose and polyvinyl alcohol to the pulverized product to be shaped or by careful adjustment of the molding conditions of the tabletting machine. With regard to the second problem cited, although the reason for the bad reproducibility can not be clearly elucidated, it seems that when the suspension or the mixed solution of the starting compounds is heated to dry, the water evaporates from the superficial portion of the suspension or solution, so that cobalt, nickel and other catalyst ingredients are irregularly distributed in the resulting catalyst, i.e. a higher concentration in the surface portion 1c of the catalyst than in the central portion.

 The main object of the invention is to provide a process for preparing catalysts used for the oxidation or ammoxidation of olefins which is an improvement over the process described in the aforementioned FR patent applications and which makes it possible to produce satisfactory catalysts. the previously indicated requirements.

 Another object of the invention is to provide a process for the ammoxidation of olefins in which unsaturated nitriles are produced in high yield and a high spatio-temporal yield.

According to one of its aspects, the invention provides a process for preparing a catalyst useful in the oxidation of olefins, this catalyst having a composition corresponding to the general formula MoacobNicFedBieXf TisAlhYiOi in which Mo is molybdenum, Co is cobalt, Ni is nickel, Fe is iron, Bi is bismuth, X is at least one metal selected from vanadium and tellurium, Ti is titanium, Al is aluminum, Y is an alkali metal,
O is oxygen and each index a, b, c, d, e, f, g, h, i and j is a number expressing an atomic ratio of the respective elements and when a = 10, b = 0 to 10, c = 0 to 10, b + c = 1 to 10, preferably 4 to 9, d = 0.1 to 7, preferably 1 to 3, e = 0.01 to 3, preferably 0.05 to 0.5 , f = 0.01 to 1, preferably 0.05 to 0.5, g = 1 to 15, preferably 2 to 10, h = 0 to 10, preferably 1 to 5, i = 0 to 4, preferably 0.005 to 0.5 and j is a number satisfying the average valence of the respective elements and in the range of 33.2 to 104.5, said process comprising the steps of:
heating a suspension or mixed solution composed of compounds containing the constituent elements of the catalyst in a proportion such that the respective constituent elements of the catalyst present in the suspension or the mixed solution satisfy said general formula, in order to concentrate or to dry the suspension or mixed solution
incorporating into the pasty or pulverulent product obtained a solution of at least one compound chosen from polyvinyl compounds and organic compounds nitrogenized in an organic solvent, the amount of said compound being in the range of 1 X to 10% by weight, preferably from 2 to 8% by weight, relative to the dry weight of the pasty or powdery product
shaping the resulting mixture into shaped articles; then
calcine shaped articles.

 In another aspect, the invention provides a process for preparing an unsaturated nitrile from an olefin which comprises contacting, in the vapor phase, at elevated temperature, an olefin mixture, and oxygen with the aforementioned catalyst.

 The preferred embodiments of the invention will now be described.

 The olefin oxidation catalyst prepared according to the process of the invention has improved olefin ammoxidation activity in which olefins, such as propylene and isobutylene, are catalytically reacted with ammonia and the high temperature vapor phase molecular oxygen in a fixed bed reactor to produce unsaturated nitriles, such as acrylonitrile and methacrylonitrile. It also exhibits increased activity for the oxidation of olefins in which olefins, such as propylene and isobutylene, are catalytically reacted with high temperature vapor phase molecular oxygen in a fixed bed reactor. produce unsaturated aldehydes, such as acrolein and methacrolein. In addition, the catalyst may be used in a fluidized bed reactor when employed as finely divided particles.

 In the process of the invention, the catalyst has a good workability and the catalytic performance is obtained with better reproducibility. When the catalyst is used to produce unsaturated nitriles or unsaturated aldehydes, the desired nitriles or aldehydes can be produced at a relatively low temperature in high yield and high space-time yield. In addition, the catalyst has high mechanical strengths and therefore does not pulverize when filled with a fixed bed reactor or when transported and does not disintegrate upon use. Thus, the catalyst has stabilized catalytic performance.

 It is crucial and indispensable in the process of the invention that: a suspension or a mixed solution consisting of compounds containing the respective constituent elements of the catalyst in proportions such that these elements satisfy the above general formula, is heated to be concentrated in a pasty product or dried into a powdery product; the dough product or the pulverulent product is incorporated in the form of 1 to 10% by weight, preferably 2 to 8% by weight relative to the dry weight of the pasty or powdery product, of a polyvinyl compound and / or of an organic compound nitrogen in the form of a solution in an organic solvent; shaping the obtained mixture into shaped particles; then the shaped articles are calcined.

 Compounds containing the respective constituent elements of the catalyst, which are used as starting materials in the process of the invention, include, for example, molybdenum-containing compounds such as molybdic acid, ammonium molybdate and trioxide. molybdenum; cobalt-containing compounds, such as cobalt nitrate, cobalt carbonate, cobalt oxide, cobalto-cobalt oxide, cobaltous hydroxide, cobaltic hydroxide, cobalt oxalate and cobalt; nickel-containing compounds such as nickel nitrate, nickel carbonate, nickel oxide, nickel-nickel oxide, nickel hydroxide, nickel hydroxide, nickel acetate, sodium oxalate, nickel and nickel chloride, iron-containing compounds such as ferrous nitrate, ferric nitrate, ferrous oxide, ferric oxide, ferrous hydroxide, ferric hydroxide, ferrous carbonate, ferrous chloride and ferric chloride; bismuth-containing compounds such as bismuth nitrate, bismuth trioxide, bismuth bichloride, bismuth trichoride, bismuth tentoxide, bismuth oxynitrate and bismuth hydroxide; aluminum-containing compounds such as aluminum nitrate, aluminum hydroxide and aluminum chloride; titanium-containing compounds such as titaniumic acid, titanium dioxide and titanium trichloride; vanadium-containing compounds such as metavanadic acid, ammonium metavanadate, vanadyl oxalate and vanadium pentoxide; tellurium-containing compounds such as telluric acid, tellurium dioxide and tellurium oxide; and alkali metal containing compounds such as nitrates, carbonates, chlorides and hydroxides.

 The compounds containing the respective constituent elements of the catalyst are dissolved or dispersed in water or an aqueous solution of acid or alkali to form a mixed solution or suspension. The preparation of such a mixed solution or suspension can be carried out at a temperature ranging from ordinary temperature to 90 ° C. The mixed solution or suspension is heated in a conventional manner to concentrate or dry to form a pasty product or powder.

 The indicated amount of a polyvinyl compound and / or a nitrogenous organic compound is incorporated in the above-mentioned pasty or pulverulent product in the form of a solution in an organic solvent and is then shaped into shaped articles and calcined. The solution of the polyvinyl compound and / or the organic nitrogen compound can be incorporated in an organic solvent, either the pasty product or the powdery product. It is, however, preferable to incorporate the solution of the polyvinyl compound and / or the nitrogenous organic compound into the powder product since the mixing operation can be easily performed and the resulting catalyst has good characteristics.

 The polyvinyl compound used in the process of the invention consists for example of polyvinyl alcohol, polyvinyl methyl ether, polyvinyl ethyl ether, polyvinylpyrrolidone, polyvinylcarbazole, polyvinyl acetal and polyvinylbutyl ether. Among them, polyvinyl alcohol, polyvinylpyrrolidone and polyvinylethyl ether are particularly preferred. The molecular weight of the polyvinyl compound is not particularly limited but is preferably in the range of about 5,000 to about 100,000.

The nitrogenous organic compound used in the process of the invention is constituted for example by aromatic amines such as aniline, N-methylaniline, N-ethylaniline, N, N-diethylaniline, N, N-dimethylaniline, N-benzylaniline, benzylamine, dibenzylamine, toluidine and diphenylamine; aliphatic amines such as methylamine, ethylamine, propylamine, dimethylamine, diethylamine, dipropylamine, trimethylamine, triethylamine and ethanolamine; amides such as formamide, acetamide, propionamide, butyramide, benzamide, nicotinamide, benzimide, N, N'-dimethylformamide, acetanilide and oxamide; nitrogen-containing heterocyclic compounds such as pyrrolidine, pyridine, 2-ethylpyridine, 2-methylpyridine, 4-methylpyridine, pyrrole, 3-methylpyrrole, 2-ethylpyrrole, 2-methylpyrrole, piperidine, 4-methylpyridine, methylperidine, 3-methylpiperidine, quinoline and morpholine; and lactams such as 2-pyrrolidone (γ-butyrolactam), 2-piperidone (6-valerolactam) and ε-caprolactam
The polyvinyl compounds and the organic nitrogen compounds can be used separately or in combination.

 The organic solvent used is not particularly limited provided that the polyvinyl compound and / or the nitrogenous organic compound can be dissolved therein. Examples of organic solvents are aliphatic monoalcohols such as methanol, ethanol, n-propanol, butanol and octanol; glycols such as ethylene glycol and propylene glycol; ketones such as acetone and methyl ethyl ketone; and esters such as ethyl acetate and ethyl propionate. Among them, aliphatic monoalcohols, glycols and ketones are preferable. The organic solvent can also be used alone or as a combination of solvents.

 Incorporation of the solution of the polyvinyl compound and / or the organic nitrogen compound in an organic solvent greatly improves the workability of the pasty or powdery product and therefore the resulting mixture can easily be shaped into shaped articles such as tablets, for example in the form of columns or spheres. When the tablets are calcined, the polyvinyl compound and / or the nitrogenous organic compound and the organic solvent are decomposed and / or volatilized to form a catalyst having many micropores in its surface portion. If an excessive amount of the polyvinyl compound and / or the nitrogenous organic compound is used, the catalyst obtained has poor mechanical strengths and is to a certain extent fragile or has a reduced catalytic activity. If the amount of the polyvinyl compound and / or the nitrogenous organic compound is too small, the desired effect can not be obtained. The suitable amount of the polyvinyl compound and / or the nitrogenous organic compound is in the range of 1 to 10% by weight, preferably 2 to 8% by weight based on the dry weight of the pasty or powdery product. The amount of the organic solvent may be in the range of 5 X to 40% by weight, preferably 5 X to 30% by weight, based on the dry weight of the pasty or powdery product. If the amount of the organic solvent is either if too low is too large, the workability, the yield and the space-time yield of the desired unsaturated aldehydes or nitriles are reduced.

 The incorporation of the solution of the polyvinyl compound and / or the organic nitrogen compound in an organic solvent improves the oxidation and ammoxidation activities of the olefins of the catalyst although the reason for this fact can not be clearly elucidated. It should be noted that the desired catalysts can not be obtained in the following cases: (1) when the polyvinyl compound or the nitrogenous organic compound is used without any organic solvent (polyvinylpyrrolidone and 2-pyrrolidone are respectively used in the comparative examples 2 and 9), (2) when using neither the polyvinyl compound nor the organic nitrogen compound but an organic solvent (ethylene glycol is used in Comparative Examples 3 and 8), (3) when using a solution of an organic substance other than the polyvinyl compound and the organic nitrogen compound in an organic solvent (using a solution of cellulose in ethanol in Comparative Example 4), (4) when neither the polyvinyl compound, the nitrogenous organic compound and the organic solvent (in Comparative Example 1), and (5) when the polyvinyl compound or the nitrogenous organic compound is used in the form of an aqueous solution ( uses respectively an aqueous solution of polyvinylpyrrolidone and an aqueous solution of 2-pyrrolidone in Comparative Examples 5 and 9).

 It is preferable that the mixture of the solution of the polyvinyl compound and / or the nitrogenous organic compound with the pasty or powdery product is shaped into shaped articles such as tablets in the usual manner by using, for example, a shaping machine. by compression, an extrusion machine or a rotary granulator, so that the tablets have a crushing strength of 1 to 4 daN per dried tablet.

When the tablets are calcined, their mechanical strengths are increased to such an extent that the tablets can be used in a fixed bed reactor. The calcination is preferably carried out in a gaseous atmosphere containing oxygen for example in air at a temperature of 4000 ° C. to 7000 ° C. and better still 450 ° to 65 ° C. for 3 to 20 hours and better still for 5 to 10 hours. If the calcination temperature is too high or too low, the catalytic activity is reduced.

 A typical example of the process of the invention is described below.

 A predetermined amount of a compound containing molybdenum, for example ammonium molybdate, is dissolved in water. A predetermined amount of a titanium-containing compound, for example, titanium dioxide, is dispersed, and predetermined amounts of a vanadium-containing compound and / or a tellurium-containing compound, for example, metavanadate, are dissolved successively. ammonium and / or telluric acid, in the ammonium molybdate solution to obtain the solution A.No dissolved in water or in an aqueous solution of nitric acid predetermined amounts of a compound containing cobalt and or a nickel-containing compound, a bismuth-containing compound, an iron-containing compound, an aluminum-containing compound and an alkali metal-containing compound, for example, nitrates of these metals to obtain solution B. The two solutions A and B are mixed together and they are heated with stirring to evaporate them to dryness. Next, the product is completely dried at a temperature of 1200.degree. C. to 2200.degree. C. for 5 to 20 hours, then spraying it into a powder and dissolving 1 to 10% by weight, based on the weight of the powder, of a polyvinyl compound or a nitrogen-containing organic compound at room temperature in 50 to 40% by weight of a solvent organic relative to the weight of the powder. The resulting solution is incorporated into the powder. The mixture is shaped into coils using a shaping machine, for example an extruder, so that the tablets have a crush strength of 1 to 4 daN per tablet. The tablets are calcined in air at a temperature of 400.degree. at 7000C, preferably from 450 to 6500C, for 3 to 20 hours, preferably 5 to 10 hours, to obtain the desired catalyst.

 In the preparation of the catalyst, a carrier can be used. As carriers, any known carrier having favorable effects on the oxidation or ammoxidation reaction involved, such as silica, diatomaceous earth, silicon carbide and carborundum, may suitably be used.

 In the oxidation or ammoxidation of olefins such as propylene and isobutylene which are carried out in the presence of the catalyst prepared by the process of inion, it is possible to use gaseous diluents which are essentially inert with respect to the oxidation or ammoxidation reaction involved. These diluents include, for example, water vapor, nitrogen gas and carbon dioxide gas. Among them, water vapor is preferred because it increases the selectivity to the desired product such as acrylonitrile, methacrylonitrile, acrolein or methacrolein and the durability of the catalyst. It is preferable to use steam from 0.1 to 5 moles and more preferably from 0.5 to 4 moles per mole of the olefin used.

 The oxidation or ammoxidation reaction of the olefins is generally carried out at atmospheric pressure although a slightly higher or slightly lower pressure may be employed. The reaction temperature is generally in the range of 300 to 5500C, preferably 320 to 5000C. The contact time is generally in the range of 0.2 to 20 seconds and preferably 0.5 to 15 seconds.

 Olefins used in catalytic oxidation or ammoxidation, such as propylene and isobutylene, are not necessarily highly purified.

Hydrocarbons which have no appreciable effect on the oxidation or ammoxidation of olefins under the particular reaction conditions, for example methane, ethane and propane, may be present in the olefin feed. The amount of these hydrocarbons preferably does not exceed 0.5 mole and more preferably 0.1 mole per mole of olefin.

 As oxygen used in the catalytic oxidation or ammoxidation reaction, pure oxygen and any oxygen-containing gas can be used. In particular, the air can advantageously be used. The relative proportion of oxygen in the olefinic feed of the catalytic oxidation or ammoxidation is generally in the range of 0.8 to 4 moles and preferably 1 to 2 moles per mole of olefin. The relative proportion of ammonia in the olefin feed of the catalytic ammoxidation is generally in the range of 0.5 to 3 moles and preferably 0.8 to 1.5 moles per mole of olefin.

The invention is illustrated by the following non-limiting examples and comparative examples. In the examples and comparative examples, the percentage conversion of propylene or isobutylene, the percentage of selectivity to acrylonitrile, methacrylonitrile, acrolein or methacrolein and the percentage yield of acrylonitrile, methacrylonitrile, acrolein or methacrolein are defined as follows.

<tb><SEP> moles <SEP> of <SEP> propylene <SEP> or <SEP> of iso
<tb> X <SEP> of <SEP> conversion <SEP> of <SEP> butylene <SEP> consumed
<tb><SEP> x <SEP> 100
<tb> propylene <SEP> or <SEP> of <SEP> moles <SEP> of <SEP> propylene <SEP> or <SEP> of iso
<tb> isobutylene <SEP> butylene <SEP> provided
<tb><SEP> moles <SEP> of desired <SEP><SEP> product
<tb> Percentage <SEP> of <SEP> ~ <SEP> produced <SEP> x <SEP> 100
<tb> selectivity <SEP> in <SEP> the <SEP> moles <SEP> of <SEP> propylene <SEP> or <SEP> of iso
<tb> product <SEP> desired <SEP> butylene <SEP> consumed
<Tb>

<SEP> moles <SEP> of desired <SEP><SEP> product
<tb><SEP><SEP>SEP><SEP><SEP><SEP> Ratio <100
<tb> desired product <SEP><SEP> = <SEP> moles <SEP> of <SEP> trotylene <SEP> or <SEP> x <SEP> 200
<tb><SEP> moes <SEP> of <SEP> orovlene <SEP> or <SEP> of iso
<SEP> butylene <SEP> provided
<Tb>
In the Examples and Comparative Examples, the crush strengths of the tablets and catalysts are determined as follows. A sample is placed on a flat test stand and then a load is applied to it. The scale (expressed in daN) for which the sample is crushed is measured with a Kiya-type hardness tester. The crush strength expressed in daN per tablet or catalyst is the average value of the charges measured for 50 samples.

Example 1

 166.1 g of ammonium molybdate (NH4) 6Mo7024.4H2O are dissolved in 200 ml of water maintained at 800 ° C.

2.2 g of telluric acid gH6TeO67 and 37.6 g of titanium dioxide gTiO are added with stirring in the ammonium molybdate solution.

 136.9 g of cobalt nitrate 2'Co (N03) 2.6H20J, 54.8 g of nickel nitrate [Ni (NO3) 2.6H20], 76.1 g of ferric nitrate [Fe (NO3) 39H2O] are dissolved and 70.5 g of aluminum nitrate [Al (NO3) 3.9H2O] in 250 ml of water maintained at 800C. In 10 ml of a 15% aqueous solution of nitric acid, 9.12 g of bismuth nitrate gBitNO 3) 3.5H 2 O are dissolved. The solution containing Co-Ni-Fe-Al and the bismuth nitrate solution is added dropwise to the above dispersion containing Mo-Te-Ti, with stirring.

 The mixture thus obtained is heated with stirring to evaporate to dryness. 100 g of the solid product obtained are pulverized. 3 g of polyvinylpyrrolidone having a molecular weight of about 40,000 in 30 g of ethanol are dissolved.

The resulting solution is incorporated into the powder and the mixture is kneaded using a kneader for about 10 minutes, then extruded using an extrusion machine to obtain tablets having a diameter of 4 mm and a length of 4 to 4 mm. 8 mm. The tablets are dried at 150 ° C. for 5 hours and then calcined in air at 55 ° C. for 5 hours to obtain a catalyst. The catalyst has a composition represented by the formula MolOCogNiZFe2Biol2TeOI1Ti5A12 in which oxygen is not present and the indices extract the atomic ratios of the respective elements (it is likewise hereinafter).

 8 ml of the catalyst thus prepared was filled with a U-shaped glass reaction tube having an inner diameter of 8 mm. A gaseous mixture of propylene, ammonia, air and water vapor with a molar ratio of the four ingredients of 1: 1 is passed through the catalyst-packed reaction tube maintained at 400 ° C. 11/2 at a flow rate of 320 ml / min. The contact time is 1.5 seconds. When 2 hours have elapsed after the start of the reaction, the reaction product is analyzed.

 The results of the analysis appear in Table I. The spatio-temporal yield of acrylonitrile is 323.3 g / l.h. The crush strength of the tablets measured before calcination and that of the catalyst are respectively 1.8 and 5.7 daN.

 The preparation of the catalyst is repeated ten times. The catalysts obtained have substantially the same characteristics as those indicated above.

Examples 2, 3 and 4.

 According to the procedure described in Example 1, catalysts having the compositions indicated in Table I are prepared and their performance in the ammoxidation of propylene is evaluated. In the preparation of the catalysts of Examples 3 and 4, ammonium metavanadate NH4Vo37 is used instead of telluric acid. All other conditions remain virtually the same.

 The results of the catalytic ammoxidation are shown in Table I.

ATBLEAUI
Ex. Catalyst Composition (Atomic Ratio) Conversion of Selectivity to Yield
N propylene (%) acrylonitrile acrylonitrile spatio
Mo Co Ni Fe Bi Te V Ti Al (%) (%) time in acrylonitrile (g / lh) 1 10 5 2 2 0.2 0.1 - 5 2 98.2 86.9 85.3 321.3 2 10 5 2 2 0.2 0.1 - 5 - 98.0 86.3 84.6 320.6 3 10 5 2 2 0.2 - 0.1 2 - 98.5 84.9 83.6 316.9 4 10 7 1 2 0.1 - 0.1 7 1 98.6 85.7 84.5 320.3
Exemols 5 to 9.

 According to the procedure described in Example 1, catalysts having the same composition as that of the catalyst described in Example 1 are prepared and their performance in the ammoxidation of propylene is evaluated.

In each of these examples, 3 g of the vinyl compound and 30 g of the organic solvent are used, which are indicated in Table II instead of 3 g of polyvinylpyrrolidone and 30 g of ethanol, all the other conditions remaining practically the same.
The results are shown in Table II.

TABLE II
Eg Solvent Polyvinyl Solvent Conversion of Selectivity to Yield in
Organic propylene (%) acrylonitrile acrylonitrile (%) (%) polyvinylpyrrolidone methanol 97.8 85.5 83.7 polyvinylpyrrolidone ethylene-98.5 86.8 85.5 glycol 7 polyvinyl alcohol ethanol 97.7 85.2 83.2 8 polyvinyl ether acetone 98.1 85.4 83.8 ethyl 9 polyvinylcarbazole methanol 98.2 85.9 84.4
Comparative Example 1

 According to the procedure described in Example 1, a catalyst having the same composition as the catalyst described in Example 1 is prepared and its performance in the ammoxidation of propylene is evaluated. In this comparative example, neither polyvinylpyrrolidone nor ethanol is used and tablets having a diameter of 5 mm and a height of 5 mm are prepared using a compression molding machine instead of an extrusion machine, all other conditions remaining virtually the same.

 The crush strength of the tablets measured before calcination and that of the catalyst are respectively 1.8 daN and 2.3 daN. The results of the catalytic ammoxidation are shown in Table III.

Comparative examinations 2 to 5.

 According to the procedure described in Example 1, catalysts having the same composition as the catalyst described in Example 1 are prepared and their performance in the ammoxidation of propylene is evaluated. In these comparative examples, the additives shown in Table III are used in the amounts shown in Table III in place of polyvinylpyrrolidone and ethanol. In Comparative Example 2, tablets were prepared using a compression molding machine as described in Comparative Example 1. All other conditions remain substantially the same.

 The results of the catalytic ammoxidation are shown in Table III.

TABLE III
Ex. Akkitive and quantity (% by weight) Conversion Selectivity Yield Comp. propyl acrylo- acrylophosphate
Nene (%) nitrile (%) acrylonitrile nitrile (%) (g / lh) 1 No additive 90.3 83.8 75.7 286.9 2 polyvinylpyrrolidone: 3 90.1 84.9 76, 4,289.6 3 ethylene glycol: 90.7 84.5 76.6 290.5 4 cellulose: 3 + ethanol: 90.9 82.1 74.6 282.8 5 polyvinylpyrrolidone: 3 + water: 30 88, 84.3 74.5 282.4 Example 10.

Using the same catalyst as that prepared in Example 1, a catalytic ammoxidation of an olefin is carried out under the same conditions as those described in Example 1. Isobutylene is used instead of propylene and the reaction temperature is 3700C, all other conditions remaining virtually the same
The conversion of isobutylene is 98.5%.

The selectivity to methacrylonitrile is 84.7%. The yield of methacrylonitrile is 83.4%.

Ex. Ll.

 Using the same catalyst as that prepared in Example 1, a catalytic oxidation of propylene is carried out under the same conditions as those described in Example 1. No ammonia is used and the reaction temperature is 3500.degree. C, all the other conditions being practically the same.

 The conversion of propylene is 98.8%. The acrolein selectivity is 94.1%. The yield of acrolein is 93.0%.

Example 12.

 Using the same catalyst as that prepared in Example 1, the catalytic oxidation of an olefin is carried out under the same conditions as those described in Example 1. Isobutylene is used instead of propylene and not use ammonia, all other conditions remaining virtually the same.

 The conversion of isobutylene is 96.1%.

The selectivity for methacrolein is 82.7%. The yield of methacrolein is 79.5%.

Comparative Example 6

 According to the same procedure as that described in Example 11, catalytic oxidation of propylene is carried out using the same catalyst as that prepared in Comparative Example 1, all other conditions remaining substantially the same.

The conversion of propylene is 92.4%. The acrolein selectivity is 87.5%. The yield of acrolein is 80.9
Example 13

According to the procedure described in Example 1, a catalyst is prepared and the catalytic ammoxidation of propylene is carried out. In the catalyst preparation stage, 0.47 g of potassium nitrate gKN037 is also used for the preparation of the mixed solution containing the constituent elements of the catalyst, so that the catalyst obtained has the composition represented by the formula Mo10Co5Ni 2Fe2BiO, 2Te0, 1Ti5Al2K0,05
All other conditions remain virtually the same.

 The conversion of propylene is 98.4%. The acrylonitrile selectivity is 87.1%. The yield of acrylonitrile is 85.7%.

Example 14.

 According to the procedure described in Example 1, a catalyst having the same composition as the catalyst described in Example 1 is prepared and the catalytic ammoxidation of propylene is carried out. In the catalyst preparation stage, 2-pyrrolidone is used instead of polyvinylpyrrolidone.

 The results of ammoxidation are shown in Table IV. The spatio-temporal yield of acrylonitrile is 324.0 g / l.h. The compressive strength of the tablets measured before the calcination and that of the catalyst are respectively 1.8 daN and 5.5 daN. The preparation of the catalyst described above is repeated ten times. The catalysts obtained have substantially the same catalytic characteristics as those of the catalyst described above.

Examples 15, 16 and 17

 According to the procedure described in Example 14, the catalysts having the compositions indicated in Table IV are prepared and their performance is evaluated in the ammoxidation of propylene. In the preparation of the catalysts of Examples 16 and 17, ammonium metavanadate [NH4VO3] is used instead of telluric acid.

All other conditions remain virtually the same
The results of the catalytic ammoxidation are shown in Table IV.

TABLE IV
Ex. Catalyst composition (atomic ratio) Conversion of Selectivity to Yield in Yield
N propylene (%) acrylonitrile acrylonitrile spatio
Mo Co Ni Fe Bi Te V Ti Al (%) (%) time in acrylonitrile (g / lh) 14 10 5 2 2 0.2 0.1 - 5 2 99.1 86.3 85.5 324.0 15 10 5 2 2 0.2 0.1 - 5 - 98.5 86.0 84.7 321.0 16 10 5 2 2 0.2 - 0.1 2 - 99.3 86.4 85.8 325 2 17 10 7 1 2 0.1 - 0.1 7 1 99.3 85.5 84.9 321.8
Examples 18 to 32.

 According to the procedure described in Example 14, catalysts having the same composition as that of the catalyst described in Example 14 are prepared and evaluated. performance in the ammoxidation of propylene. In each of these examples, use is made of 3 g of the nitrogenous organic compound and 30 g of the organic solvent which are given in Table V instead of 3 g of 2-pyrrolidone and 30 g of ethanol, all the other conditions remaining substantially the same. same.

 The results are shown in Table V.

Table V
Eg Organic nitrogen compound Organic solvent Conversion Selectivity Yield
N propylene acrylonitrile (%) nitrile (%) (%) 18 aniline ethylene glycol 98.2 86.1 84.6 19 ethylene glycol ethylene glycol 97.4 84.3 82.1 20 dipropylamine ethanol 97.9 84.7 82.9 21 triethylamine ethanol 98.0 85.2 83.5 22 N-methylaniline methanol 98.2 86.3 84.7 23 2-plperidone ethylene glycol 98.5 84.9 83.9 24 e-caprolactam methanol 98, 0 85.2 83.5 25 pyrrolidine acetone 97.7 85.4 83.4 piperidine methanol 97.1 85.6 83.1 27 2-ethylpyrrole ethanol 98.0 86.0 84.3 28 3-methylpiperidine ethenol : 15 + ethylene glycol: 97.9 85.8 84.0 29 acetamide propanol 97.2 84.5 82.1 benzimide octanol: 10 + ethanol: 98.7 84.9 83.8 31 nicotinamide methanol 98, 4 85.1 83.7 32 N, N'-dimethylformamide ethylene glycol 97.6 84.6 82.6 Compound 7 to 12.

 According to the procedure described in Example 14, catalysts having the same composition as the catalyst described in Example 14 are prepared and their performance in the ammoxidation of propylene is evaluated. In these comparative examples, the additives shown in Table VI are used in the amounts shown in Table VI instead of polyvinylpyrrolidone and ethanol.

In Comparative Example 7, the tablets are prepared using a compression molding machine as described in Comparative Example 1. All other conditions remain substantially the same.

 The results of the catalytic ammoxidation are shown in Table VI.

TABLE VI
Ex. Additive and quantity (% by weight) Conversion Selectivity Yield Comp. from propylene to acrylo- acrylospatio
N (%) nitrile (%) nitrile (%) acrylonitrile (g / lh) 1 No additive 90.3 83.8 75.7 286.9 7 2-pyrrolidone: 3 91.4 84.7 77 , 4,293.3 4 cellulose: 3 + ethanol: 90.9 82.1 74.6 282.8 8 2-pyrrolidone: 3 + water: 30 89.1 83.2 74.1 280.8 9 2- pyrrolidone: 15 + ethanol: 89.2 86.1 76.8 291.1 aniline: 0.5 + ethyleneglycol: 91.8 84.0 77.1 292.2 11 benzene: 3 + ethyleneglycol: 30 97 7 84.6 77.6 294.1 12 acetic acid: 3 + ethanol: 92.0 84.3 77.6 294.1 Example 33.

 Using the same catalyst as that prepared in Example 14, the catalytic ammoxidation of an olefin is carried out under the same conditions as those described in Example 14. Isobutylene is used instead of propylene and the temperature of reaction is 370 ° C, all other conditions remaining virtually the same.

The conversion of isobutylene is 99.0%
The selectivity to methacrylonitrile is 84.4%. The yield of methacrylonitrile is 83.6%.

Example 34

 Using the same catalyst as that prepared in Example 14, the catalytic oxidation of propylene is carried out under the same conditions as those described in Example 14. Ammonia is not used and the reaction temperature is 3500C, all other conditions remaining virtually the same.

 The conversion of propylene is 92.2%. The selectivity to acrolein is 83.7%. The yield of acrolein is 93.0%.

Example 35

 Using the same catalyst as that prepared in Example 14, the catalytic oxidation of an olefin is carried out under the same conditions as those described in Example 4. Isobutylene is used instead of propylene and does not use ammonia, the other conditions remaining almost the same.

 The conversion of isobutylene is 96.7%.

The methacrolein selectivity is 82.0 S. The yield of methacrolein is 79.3%.

COMPARATIVE EXAMPLE 13.

 According to the procedure described in Example 34, the catalytic oxidation of propylene is carried out with the same catalyst as that prepared in Comparative Example 1, all other conditions remaining substantially the same.

 The conversion of propylene is 91.9%. The selectivity to acrolein is 87.0%. The yield of acrolein is 80.0 t.

Example 36.

According to the procedure described in Example 14, a catalyst is prepared and the catalytic ammoxidation of propylene is carried out. In the catalyst preparation stage, 0.47 g of potassium nitrate KNO 2 is also used for the repair of the mixed solution containing the constituent elements of the catalyst, and the catalyst thus obtained has the composition represented by the formula
Mo10Co5Ni2Fe2Bi0,2Te0,1Ti5Al2K0,05
All other conditions remain virtually the same.

 The conversion of propylene is 98.6%. The acrylonitrile selectivity is 87.0%. The yield of acrylonitrile is 85.8%.

Claims (16)

 A process for preparing a catalyst useful in the oxidation and ammoxidation of olefins, said catalyst having a composition corresponding to the general formula  Mo in which Mo is molybdenum, Co is cobalt, Ni is nickel, Fe is iron, Bi is bismuth, X is at least one metal selected from vanadium and tellurium, Ti is titanium, Al is is aluminum, Y is an alkali metal, 0 is oxygen and each index a, b, c, d, e, f, g, h, i and j is a number expressing the atomic ratio of the corresponding elements and when a = 10, b = 0 to 10, c = 0 to 10, b + c = 1 to 10, d = 0.1 to 7, e = 0.01 to 3, f = 0.01 to 1, g = 1 to 15, h = 0 to 10, i = 0 to 4 and j is a number satisfying the average valence of the elements and in the range of 33.2 to 104.5, said process comprising the steps of  heating a suspension or mixed solution consisting of compounds containing the constituent elements of the catalyst in proportions such that the constituent elements of the catalyst present in the suspension or mixed solution ~ satisfy said general formula, to concentrate or dry the suspension or mixed solution;  incorporating into the pasty product or powder obtained a solution of at least one compound chosen from polyvinyl compounds and organic compounds nitrogen-containing in an organic solvent, the amount of said compound being in the range of 1% to 10% by weight relative to dry weight of the pasty or powdery product  shaping the resulting mixture into shaped articles; then  calcine shaped articles.  2. The method of claim 1, wherein the polyvinyl compound is selected from polyvinyl alcohols, polyvinyl ethers, polyvinylpyrrolidones and polyvinylcarbazoles.  3. Process according to claim 1, wherein the nitrogenous organic compound is chosen from aromatic amines, aliphatic amines, amides, nitrogenous heterocyclic compounds and lactams.  The process according to claim 1, wherein the nitrogenous organic compound is selected from aniline, N-methylaniline, ethylamine, dipropylamine, triethylamine, acetamide, nicotamide, benzimide, N, N'-dimethylformamide, pyrrolidine, 2-ethylpyrrole, piperidine, 3-methylpiperidine, 2-pyrrolidone, 2-piperidone and ε-caprolactam.  5. Process according to any one of claims 1 to 4, wherein the amount of said compound chosen from polyvinyl compounds and nitrogenous organic compounds is in the range of 2 to 8% by weight relative to the dry weight of the product. pasty or pulverulent pulp.  6. Process according to any one of claims 1 to 5, wherein said organic solvent is selected from aliphatic monoalcohols, glycols, ketones and esters.  7. A process according to any one of claims 1 to 6, wherein the amount of said organic solvent is in the range of 5 to 40% by weight based on the dry weight of the pasty or powdery product.  8. Process according to claim 1, wherein a solution of aniline in ethylene glycol is incorporated into the pasty or powdery product.  The process according to any one of claims 1 to 8, wherein said mixture of the pasty or powdery product and the solution of the compound selected from polyvinyl compounds and nitrogenous organic compounds is shaped into shaped articles such that the articles The shaped articles obtained have a crush strength of 1 to 4 daN per tablet.  10. A process according to any one of claims 1 to 9, wherein the shaped articles are calcined in a gaseous atmosphere containing oxygen at a temperature of 4000C to 7000C for 3 to 20 hours.  11. A process according to any one of claims 1 to 9, wherein the shaped articles are calcined in a gaseous atmosphere containing oxygen at a temperature of 4500C to 6500C for 5 to 10 hours  A process for preparing an unsaturated nitrile from an olefin which comprises bringing a mixture of olefin, anuoniac and oxygen into contact with the catalyst prepared in accordance with the vapor phase at an elevated temperature. the process of any one of claims 1 to 11.  The process according to claim 12, wherein the molar ratio of ammonia to olefin in the mixture is in the range of 0.5 / 1 to 3/1 and the molar ratio of oxygen to olefin in the mixture is in the range of 0.8 / 1 to 4/1.  14. A method according to one of claims 12 or 13, wherein said mixture further contains 0.1 to 5 moles of steam per mole of olefin.  The method of any one of claims 12 to 14, wherein said mixture is contacted with said catalyst at a temperature of 3000C to 5500C for 0.2 to 20 seconds.  The process of any one of claims 12 to 15, wherein said olefin is propylene or isobutylene and said unsaturated nitrile is acrylonitrile or methacrylonitrile.