AU5173799A

AU5173799A - Method for making acrolein from propylene by redox reaction

Info

Publication number: AU5173799A
Application number: AU51737/99A
Authority: AU
Inventors: Gilles Descat; Eric Etienne; Charlotte Pham; Jean-Pierre Schirmann; Michel Simon
Original assignee: Atofina SA
Current assignee: Arkema France SA
Priority date: 1998-08-21
Filing date: 1999-08-18
Publication date: 2000-03-14
Also published as: FR2782512A1; EP1105364A1; KR20010079661A; FR2782512B1; ID29798A; BR9913133A; JP2002523386A; MXPA01001869A; CA2351632A1; CN1313844A; WO2000010955A1

Description

WO 00/10955 PCT/FR99/02005 PROCESS FOR THE MANUFACTURE OF ACROLEIN FROM PROPYLENE BY REDOX REACTION The present invention relates to the manufacture 5 of acrolein from propylene by oxidation according to a redox reaction. The invention also relates to the use of a solid mixed oxide composition as redox system in the said reaction. At the present time acrolein is industrially 10 produced by vapour phase catalytic oxidation of propylene. All the attempts to improve this process have hitherto been concerned with the development of catalysts which give the highest possible conversion of propylene and the highest possible selectivity for the 15 desired acrolein. Thus, French Patent No. 2 093 773 describes the manufacture of acrolein by vapour phase catalytic oxida tion of propylene with molecular oxygen in the presence of an oxide catalyst in which the composition of the 20 catalytic elements, expressed as atomic ratio, is the following: C02.0-20.oFeo.

1 i 510 W - .

0 Mo2 -1i sSio s-is. oZo. os-1.0 with W + Mo = 12.0 and Z denoting an alkali metal. This catalyst can be prepared by mixing aqueous 25 solutions of ammonium molybdate and of ammonium paratungstate, adding solutions of cobalt nitrate, of iron nitrate and of bismuth nitrate to the aqueous mixture and then adding an aqueous solution of an alkali metal hydroxide or carbonate and then colloidal silica 30 as a source of silicon, by moulding the substance obtained and by calcining it at 350-600*C in a stream of air. US Patent No. 3 855 308 describes the preparation of acrolein by vapour phase catalytic 35 oxidation of propylene with molecular oxygen in the presence of an oxide catalyst in which the composition -2 of the catalytic elements, expressed as atomic ratio, is the following: Co 2

.

0

-

2 .oFeo..

1 o.oBio. 1.

1 0 .oWO.5- 1 0 Mo 2 .o- 1 1 .sSiO.s 1 s.

0 Tlo.Oos- 3 .OZo-3.o 5 with W + Mo = 12.0 and Z denoting an alkali metal or alkaline-earth metal. The raw, materials employed for forming the catalyst may be the oxides of the various metals, but also, depending on circumstances, the nitrates, carbonates or 10 hydroxides. In the case of Mo and W, the salts of acids, such as ammonium molybdate and ammonium tungstate, are recommended. Thus, according to this US patent a catalyst is prepared by mixing aqueous solutions of ammonium molybdate and of ammonium paratungstate 15 respectively, by adding solutions of cobalt nitrate, of iron nitrate and of bismuth nitrate respectively, and then an aqueous solution of alkali metal hydroxide or carbonate and then colloidal silica as a source of silicon, by concentrating the system by evaporation, by 20 adding a support if necessary and by following with an evaporation, a mixing of the resulting substance and a calcination at 350-600 0 C. Japanese Patent Showa 45-125 359 describes a vapour phase process for the manufacture of acrolein by 25 catalytic oxidation of propylene with air or oxygen in the presence of a catalyst of formula: NiaCobFecBidMeeHhMofOg in which: - a = 0-20, b = 0-20 with a + b between 0.5 and 20, 30 c = 0.5-8, d = 0.1-7, 0 < e5 2, h = 0-0.3, f = 12, g = 36-90; - Me is one out of Sn, Zn, W, Cr, Mn and Ti; and - H is at least one out of K, Rb and Cs. To prepare this catalyst, aqueous solutions of Ni, Co, 35 Fe, K (and/pr Rb, Cs), Bi and Me compounds may be added to an aqueous solution of a molybdenum compound -3 (ammonium molybdate, molybdic acid or molybdenum oxide), then a support such as alumina, silicon carbide and silica (silica sol or silica gel) may be added and then the resulting mixture is heated to dryness, is calcined 5 at approximately SOO 0 C and is converted into pastilles. French patent No. 2 534 904 describes a catalyst for the manufacture of unsaturated aldehydes, especially acrolein and methacrolein, by vapour phase oxidation of propylene, of isobutylene or of tertiary butanol with a 10 gas containing molecular oxygen. This catalyst is represented by the general formula: BiaWbFeModA.BfCAOx in which: - A represents nickel and/or cobalt; 15 - B represents one or more elements chosen from alkali and alkaline-earth metals and thallium; - C represents one or more elements chosen from phosphorus, arsenic, boron, antimony, tin, cerium, lead and niobium; 20 - D represents one or more elements chosen from silicon, aluminium, zirconium and titanium; and - a, b, c, d, e, f, g, h and x represent the atomic proportions of the individual elements, and if d is taken as e 1ual to 12: 0.1 5 a : 10; 0.5 < b 5 10; 25 0.1 c 9 10; 2 e,. 20; 0.001 : f S 10; 0 5 g 5 10; 0 5 h : 30; and - x is the amount of oxygen bound to the other elements and depends on their oxidation states, bismuth being introduced in the form of an oxide 30 obtained beforehand by calcining, between 600 and 9000C, a mixture of a bismuth compound and a tungsten compound. The Applicant Company has now discovered that acrolein can be manufactured 'by. gas phase oxidation of propylene in the absence of -molecular oxygen by reacting 35 propylene with a particular solid mixed oxide -4 composition which acts as a redox system and supplies the oxygen necessary for the reaction. The advantages of this new process, using the redox route and no longer the catalytic route, are the 5 following: - the limitation of the overoxidation of the products formed, which takes place in the presence of molecular oxygen; according to the present invention, since the operation is carried out in 10 the absence of molecular oxygen, the formation of CO (carbon monoxide and carbon dioxide), degradation products, is reduced, and this allows the selectivity for dcrolein to be increased, as shown hereinafter by the Comparative Example 4; 15 - the selectivity for acrolein remains good when the degree of reduction of the solid composition increases; - once it has undergone a reduction and a gradual loss of its activity, the solid composition can be 20 easily regenerated by heating in the presence of oxygen or of an oxygen-containing gas after a certain period of use; after the regeneration the solid recovers its initial activity and can be employed in a new reaction cycle; 25 - the separai-n -ofthe stages o reduction of the solid composition and of its regeneration makes it possible: - to increase the selectivity for acrolein; and - to increase the partial pressure of propylene, 30 such a partial pressure of propylene feed no longer being limited by the existence of an explosive region of the propylene + oxygen mixture. The subject-matter of the present invention is 35 therefore firstly the use of a solid mixed oxide composition of formula (I); -5 M0 2 BiaFebCOcNidS ieKfCrgOx (I) in which: - a is between 0.5 and 5, limits included, - b is between 0.1 and 10, limits included, 5 - c is between 0.5 and 10, limits included, - d is between 0 and 10, limits included, - e is between 0 and 15, limits included, - f is between 0 and 1, limits included, - g is between 0.1 and 2, limits included, and 10 - x is the quantity of oxygen bonded to the other elements and depends on their oxidation states, in the manufacture of acrolein by propylene oxidation, the said solid composition reacting with the propylene according to the redox reaction (1): 15 solidoxid 2 ze 8 + propylene -+ solidraucad + acrolein (1) . The oxides of the various metals forming part of the composition of the mixed- oxide of formula (I) can be employed as raw materials in the preparation of this composition, but the raw materials are not restricted to 20 the oxides; other raw materials which may be mentioned are: - in the case of molybdenum, ammonium molybdate and molybdic acid, - in the case of bismuth, iron, cobalt and nickel, 25 the nitrates, carbonates and hydroxides, such as bismuth nitrate, ferric nitrate, cobalt nitrate and nickel nitrate, - in the case of chromium, chromium nitrate, and - in the case of potassium, potassium hydroxide, 30 carbonate or nitrate, and, in general, any compounds capable of forming an oxide by calcination, namely metal salts of organic acids, metal salts of inorganic acids, metal complex compounds, organometallic compounds and the like. 35 The source of silicon generally consists of colloidal silica.

The subject-matter of the present invention is a process for the manufacture of acrolein from propylene, according to which process gaseous propylene is reacted with a solid composition of formula (I) as defined 5 above, while operating at a temperature of 200 to 600"C, especially from 25P to 450"C, at a pressure of 1.01 x 10' to 1.01 x 106 Pa (0.1 to 10 atmospheres), especially of 5.05 x 104 to 5.05 x 105 Pa (0.5-5 atmospheres), and with a residence time of 0.01 second to 90 seconds, 10 especially of 0..1 second to 30 seconds, in the absence of molecular oxygen, thus carrying out the redox reaction (1) as indicated above. In accordance with particular embodiments of the present invention the gaseous propylene may be 15 introduced as a mixture with an inert gas such as nitrogen and/or with water (water vapour). During the redox reaction (1) the solid composi tion undergoes a reduction and a progressive loss of its activity. This is why, once the solid composition has 20 changed to the reduced state, regeneration of the said solid composition is conducted according to reaction (2) solidreducea + 02 -> solid 7 stzed (2) by heating in the presence of an excess of oxygen or of 25 an oxygen-containing gas at a temperature of 250 to 500 0 C, for the time necessary for the reoxidation of the solid composition. After the regeneration, which may be performed in temperature and pressure conditions that are 30 identical with or different from those of the redox reaction, the solid composition recovers an initial activity and can be employed in a new reaction cycle. The redox reaction (1) and the regeneration can be conducted in a two-stage device, namely a reactor and 35 a regenerator which function simultaneously and in which -7 two charges of solid composition alternate periodically; the redox reaction (1) and the regeneration can also be conducted in the same reactor by alternating the reaction and regeneration periods. 5 The preparation of- acrolein according to the invention is performed according to a stoichiometric and not catalytic reaction. The following examples illustrate the present invention without, however, limiting its scope. In the 10 formulae shown in these examples x is the quantity of oxygen bonded to the other elements and depends on -their oxidation states. The conversions, selectivities and yields are defined as follows: 15 number of moles of prppylene which have reacted conversion (M) .

x 100 number of moles of propylene introduced 20 selectivity for number of moles of acrolein formed acrolein () = X 100 number of moles of propylene which have reacted 25 selectivity for number of moles- of acrylic acid formed acrylic acid (I) X 100 number of moles of .propylame which have reacted EXAMPLE 1 30 (a) Preparation of a solid of formula Mo 1 2 Bi2Fe 3

.

7 Ni 2 .SCo 4

.

7 SiiKo.oaCro.sOX 205.8 g of Co(N0 3 )2-6H 2 0, 113.8 g of Ni(NO2)2-6H20, 224.9 g of Fe(NO 3

)

3 -9H20 and 1.22 g of KNO2 are dissolved in 420 ml of distilled water at ambient temperature. 35 76.7 g of Bi(NOs) 3 -5H 2 0 are dissolved, also at ambient temperature, in 100 ml of distilled water acidified with 16.67 ml of HN0 3 at a concentration of 68 % by volume.

30.1 g of Cr (NO 3 )'9H20 are dissolved in 20 ml of distilled water, also at ambient temperature. 318.7 g of

(NH

4 ) 6 Mo,0 2 44H 2 0 are dissolved in 900 ml of distilled water at 400C. 5 The solution containing the bismuth and that containing the chromium are poured successively, with stirring, into the solution containing Co, Ni, Fe and K. The resulting solution is next poured, still with stirring, into the solution containing the molybdenum. 10 23.7 g of colloidal silica (at a concentration of 40 mass%) are then sprinkled into it. The resulting mixture is heated to 800C for 1.5 hours and is then dried for 12 hours at 140"C. The solid obtained is calcined for 6 hours at 500"C in air. The various metals 15 are present in this solid in the atomic ratios shown in the title of this example. (b) Preparation of acrolein from propylene by redox reaction 200 mg of this solid are charged into a tubular 20 reactor at 340*C and are then purged with a continuous stream of 11.5 ml/min of helium. 2 x 106 mol of propylene are injected onto the solid in order to conduct the redox reaction of the propylene and the solid. The propylene conversion is 93.3 %, with 25 selectivities for acrolein and acrylic acid of 78.0 % and 2.5 % respectively. EXAMPLE 2 After the reaction of Example 1 (b) has been conducted, the same solid is subjected again to four 30 successive propylene injections in the same test condi tions as in Example 1. The performances obtained are reported in Table 1.

-9 Table 1 Injection Propylene Selectivity Selectivity No. conversion for acrolein for acrylic (%) (%) acid (%) 1 88.9 76.8 3.0 2 76.1 76.8 3.3 3 64.5 71.3 3.6 4 56.5 66.7 3.2 EXAMPLE 3 5 After the reducing treatment of Example 2 the solid is regenerated for 1 hour in air at 340 0 C and then replaced under a flow of helium. Four successive new injections of 2 x 10~6 mol of propylene are directed onto the solid in order to conduct the redox reaction of the 10 propylene and the solid. The performances obtained are reported in Table 2. Table 2 Injection Propylene Selectivity Selectivity No. conversion for acrolein for acrylic (%) (%) acid (%) 1 93.0 80.6 3.9 2 84.0 76.7 3.2 3 65.1 70.9 3.5 4 51.6 67.1 2.9 15 EXAMPLE 4 (comparative): Preparation of acrolein by the catalytic route 200 mg of a solid prepared according to Example 1 are charged into a tubular reactor at 340 0 C and are then purged with a continuous flow of 11.5 ml/min of - 10 air. Five injections containing 2 x 10~' mol of propylene are directed onto the solid, which in this case is the catalyst of the reaction. The propylene conversion is 94.6 % with selectivities for acrolein and acrylic acid 5 of 75.2 % and 3.2 % respectively.

Claims

1. Use of a solid mixed oxide composition of formula (I): Mo

2 Bia Feb COc Nid Sie Kf CrgOx (I) 5 in which: - a is between 0.5 and 5, limits included, - b is between 0.1 and 10, limits included, - c is between 0.5 and 10, limits included, 10 - d is between 0 and 10, limits included, - e is between 0 and 15, limits included, - f is between 0 and 1, limits included, - g is between 0.1 and 2, limits included, and x is the quantity of oxygen bonded to the other 15 elements and depends on their oxidation states, in the manufacture of acrolein by propylene oxidation, the said solid composition reacting with the propylene according to the redox reaction (1): solid.iaisea + propylene -+ sOlidreuced + acrolein (1). 20 2. Process for the manufacture of acrolein from propylene, characterized in that gaseous propylene is reacted with a solid composition of formula (I) as defined in Claim 1, while operating at a temperature of 200 to 600*C, at !a pressure of 1.01 x 10 4 to 25 1.01 x 10' Pa (0.1 to 10, atmospheres) and with a residence time of 0.01 second to 90 seconds, in the absence of molecular oxygen, thus carrying out the redox reaction (1) as indicated in Claim 1.

3. Process according to Claim 2, characterized in 30 that the gaseous propylene is introduced as a mixture with an inert gas such as nitrogen and/or with water.

4. Process according ho either of Claims 2 and 3, characterized in that the redox reaction (1) is conducted at a temperature 6f 250 to 450*C. 35

5. Process according to one of Claims 2 to 4, characterized in that the, redox reaction (1) is conducted at a pressure of 5.05 x 10 - 5.05 x 10s Pa (0.5-5 atmospheres). 12

6. Process according 'to one of Claims 2 to 5, characterized in thit the redox reaction (1) is conducted with a reidence time of 0.1 second to 30 seconds. 5

7. Process according to one of Claims 2 to 6, characterized in that once the solid composition has changed to the reduced state, the regeneration of the said solid composition is conducted according to reaction (2): 10 solidreduced + 02 -+;solidxiaiz.d (2) by heating in the pre ence of an excess of oxygen or of an oxygen-containing gas at a temperature of 250 to 500 0 C, for the time neI esary. for the reoxidation of the solid composition. 15

8. Process accor ng to Claim 7, characterized in that the redox reaction (1) and the regeneration are conducted in a two-stige device, namely a reactor and a regenerator which function simultaneously and in which two charges of solid composition alternate periodically. 20

9. Process according to Claim 7, characterized in that the redox reaction (1) and the regeneration are conducted in the same reactor by alternating the reaction and regeneration periods. I