CS212584B1 - Method of continuous production of metaktolein and/or metacrylic acid - Google Patents

Abstract

The invention relates to continuous production methacrolein and / or methacrylic acid, which is carried out by tert-butyl oxidation organic compounds by oxygen or oxygen-containing gas in the gas phase at 200-550 ° C, usually in the presence aqueous vapor and / or inert gas, in the presence of a type catalyst Mo Bi, Fe X. Si K.O, a b cd e f g ' where X is at least one of the elements selected of the group consisting of antimony elements cobalt, nickel, titanium, manganese, copper, thallium and jndium, a, b, c, d, e, f, g, mean! the atomic ratios of these elements, where a is 1 to 16, b is 0.1 to 3, c is 0.1 to 4, d is 0.1 to 8, e is 0.1 to 3, f is 0.01 to 0.5 and g has a value which is determined in dependence on power and atomic ratios others. elements.

Description

The invention aa relates to the continuous production of gas phase methacrolein and / or methacrylic acid on the basis of widely available petrochemical feedstocks using selective oxidation catalysts.

It is known (Seaboth H., Freiberg J., Lficke B .: Chem. Techn. 30. 465 (1978); U.S. Pat.

423 329; me p. U.S. Pat. 52-9651, 47-22756) oxidation of isobutene to methacrolein and in the second stage to methacrylic acid, on multi-component oxide catalysts, in particular based on molybdenum, antimony, cobalt, iron, potassium, bismuth, phosphorus, chromium, silica, silicon.

A disadvantage is the need for pure isobutene as a starting material. When the butadiene-pyrolysis of the C 1 -fraction is used, besides methacrolein, 1,3-butadiene and Saler compounds are also formed.

A varied mixture makes it difficult to isolate and can adversely affect catalyst life. Process for the simultaneous production of 1,3-butadiene and methacrolein by oxidation of butene mixtures with molecular oxygen in the presence of a catalyst of the formula MOjgBi

-Be _f

-10% 5% .010.1

-8 ^{Fe Co} 012 1240 ^Nl 0-1, Th

Where Q is phosphorus, arsenic, boron, cerium; R is potassium, rubidium, cesium;

0,1-12 x is the number of oxygen atoms corresponding to the powers of other elements, it solves another way [jap. U.S. Pat. 51 - 27859 (1976)], and in addition to the problems already mentioned, homogeneity of the catalysts is not sufficiently addressed.

However, in recent times, a number of brief, respectively. superficial information! on the production of methacrolein, methacrylic acid methyl methacrylate by oxidation of tert-butyl alcohol, which was previously obtained by the selective hydration of isobutene from the de-butadiene pyrolysis C 1 fraction [Hasnike T., Matsuzawa H .: Hydrocarbon Process. 52, No 2, 105 (1979); Davis J. C .: Chem. Eng. 82, No. 15, 17 (1978); Chem. Eng. News 56. No 19, 16 (1978)), wherein the oxidation of tert-butyl alcohol in the presence of water vapor is carried out in two steps.

However, any catalyst data is missing. However, in one case [jap. U.S. Pat. 51 113807 (1976) 3 are also known for the high temperature production of methacrolein, methacrylic acid and / or 1,3-butadiene from a gas mixture containing oxygen, tert-butyl alcohol or isobutylene and / or n-butenes by passing through a catalyst of the general formula h i wherein X - b, Cs and / or T1; Y = Se, Zn, Nb, V, Ru; a = 12; b = 0.2 to 20; c, d, e, f =

0,2 to 12,. = 0.01 to 4, wherein, for example, a gas mixture consisting of 5 vol.

tert-butanol, 12 vol.% oxygen, 48 »v. nitrogen, 35 vol.% water vapor pressure at a temperature of 360 C ^J 9 contact inb <; 3.6 s, the overall yield of methacrolein and methacrylic acid was 34% mel.

In the second case, the data on the low temperature oxidation of tert-butyl alcohol and tert-butyl tert-butyl ether and methacrolein (cf. author's certificate 202 470) on the elements and the components respectively. compounds of elements IX. groups, V.b, VI.b and VII.b of the Periodic Table of the Elements.

In both cases, however, there are problems with the low homogeneity of the catalyst and the resulting lower service life. On the other hand, the preparation of a homogeneous multi-component oxide catalyst [cf. aut. certificate, 85 016 (1979)], but only for the oxidation of olefins in the gas phase, in particular propene to acrolein and isobutene to methacrolein.

Thus, the advantages of the known processes take advantage of and the problems of producing methacrolein and / or methacrylic acid from petrochemical raw materials are solved by the method of the present invention.

According to the invention, a process for the continuous production of methacrolein and / or methacrylic acid by oxidation of tert-butyl organic compounds alone or together with isobutene, oxygen or oxygen-containing gas in the gas phase at 200 and 550 ° C, usually in the presence of water vapor and / or gas, under the catalytic action of a multi-component oxidation catalyst based on molybdenum, bismuth and iron, such that the reaction is carried out with a catalyst of the type Si Si, i.e. Si KpO and cd efg where Mo, Bi, Fe, Si, K o molybdenum, bismuth, iron, silicon, potassium and oxygen,

X is at least one of cobalt, antimony, nickel, titanium, manganese, copper, thallium and indium, and a, b, c, d, e, f, g are atomic ratios of those elements where a is , up to 16, b is 0.1 to 3, c is 0.1 to 4, S is 0.1 to 8, e is 0.1 to 3, f is 0.01 to 0.5 and g has a value that The tert-butyl alcohol, diisobutenes, tert-butyl alkyl ether of 2 to 5 alkyl and isobutanol are used as tert-butylated compounds as reaction to the valence and atomic ratios of the other elements.

The advantage of the process according to the invention is the raw material availability and the easy possibility of obtaining tert-butyl alcohol, primarily in the form of aqueous solutions from a mixture of C-4-olefins by selective hydration of isobutene on sulfonated resins (cf. Aut. Certificate 173 934) and other acids, even from crude. pyrolysis of C 1 -fraction (Czechoslovakian Certificate 199 849) without the need to concentrate tert-butyl alcohol.

Furthermore, the possibility of simple production of isobutyl tert-butyl ether, the ether being a donor of up to 2 molecules of the intermediate isobutene. Another advantage is the low energy consumption and the ease of heat dissipation due to in situ water generation. Then high selectivity but desired products.

An advantage is also an efficient homogeneous multicomponent catalyst in the preparation of which the use of a combination of citric acid or tartaric acid, ammonium hydroxide and nitric acid ensures mainly due to the complexity of keeping the multi-component mixture in solution until the paste is thickened and dried or the solution is evaporated. drying room.

The easy maintenance of constant operating conditions guarantees perfect homogeneity of the catalyst and reliable reproducibility of the production of the catalyst in tubular quantities.

In addition to oxygen, air or other oxygen-containing gas, such as carbon dioxide with oxygen, low oxygen nitrogen, and the like, it is desirable to increase the activity of these gases by ozonization, additives, resp. preliminary partial formation of atomic oxygen.

The tert-butylated organic compounds of the present invention include, in particular, tert-butyl alcohol, aqueous tert-butyl alcohol solution, isobutyl tert-butyl ether, sec-butyl tert-butyl ether and n-butyl tert-butyl ether, propyl tert-butyl ether, isopropyl tert-butyl ether, amyl tert-butyl ethers.

Furthermore, diisobutenes and isobutene-isobutanol precursor can also be added. The inert gas function can be filled primarily with water vapor, carbon dioxide, nitrogen, argon, helium, to a lesser extent carbon monoxide.

In the preparation of the catalyst, it is important not only to maintain the process, but above all to the presence of citric acid or tartaric acid, or a mixture of both. Similarly effective but more expensive is malic acid and other polybasic organic acids and hydroxy acids.

The oxidation products obtained are generally isolated. The main products, methacrolein and methacrylic acid are either the final product or a monomer, but most often methacrolein leads to dooxidation to methacrylic acid by some known methods and the acid

2) 2584 methacrylic for esterification alcoholate, Si addition, optionally polyaddition of oxiranes and alkyloxiranes. The isobutane formed is most commonly recirculated or isolated. Similarly, most commonly unconverted starting materials are recirculated.

In setting the molar ratios of the feedstocks, not only maximum selectivity is important, i.e. short contact times (from fractions of a second to 5 pigs), but also high production and oxidation safety, so it is important to respect the known explosion limits of gases and vapors.

Further details of the method of the invention as well as other advantages are evident from the examples.

Example 1

In a 500 cm ^ of distilled water was dissolved 40 g of citric acid monohydrate, 11 g of Co (N0 _{3) second} DH 3 O, 4.8 g Fe (NO ₃ ) ₃ . 9H ₂ O, 3.4 g Li (NO ₃ ) ₂ . 6H ₂ O.

Further, in 200 cm @ dilute nitric acid (conc. 42% wt.) Was dissolved 5.8 g of Bi _{(NO3) 3.} The 5 H ₂ O and the two solutions are combined together and with aqueous NH 4 OH O conc.

55 wt. 25.4 g of ammonium heptamolybdate tetrahydrate and 0.03 g of KOH dissolved in 200 cm &lt; 3 &gt; of water are added.

The solution thus obtained is evaporated under constant stirring on a water bath until formation. The paste is then dried for 5 hours at 120 ° C and finally put into a muffle oven with the following temperature program: 1 hour at 200 ° C, 1 hour at 250 ° C, 1 hour at 300 ° C, 2 hours at 350 ° C, 1 h at 400 ° C and 2 h at 420 ° C.

The obtained catalyst precursor consisting (in mass 55) of 7.3 molybdenum oxide, 9.8 bismuth oxide, 10.0 cobalt oxide, 3.4 iron oxide, 3.1 nickel oxide is tabletted into 1 x 3 mm cylindrical tablets. and then calcined for 6 h at 450 ° C.

•with

From the catalyst thus prepared, 10 cm are placed in a drawn-glass reactor of 800 mm in length and 10 mm in internal diameter. Under the layer and above the catalyst layer, Rashig books of refractory glass are placed in 10 cm increments. After the reactor has been heated to the desired temperature, an aqueous tert-butyl alcohol solution is fed to the reactor head together with air so that mol. oxygen: tert-butyl alcohol: water ratio = 1.2: 1: 12.3 and catalyst loading with tert-butyl alcohol 0.075 g. cmj ^^. h ^- '.

The reaction product is collected in a cooled separator, respectively. in a freezer, analyzes and separates, eventually leading to dooxidizing and processing, whether to alkyl methacrylic esters or polyoxyalkylene glycol monomethacrylates.

The results of the one-stage oxidation are shown in Table 1.

Table 1 co p

O

H

Λ >>

P

X »β

C

XD

P β

£>

OJ β

> O

WHAT

ÍH ω

p <0 • H 3 N H

O £ £ 3> o β 44 O * —I W CO

CO «i>

β o

«

ΛΉ XD Φ CJH CO o t *

044 ttf CO CO P Φ f f-4 Θ co «-» co β # P ¹ - · • rt β> β • rt

H O Φ N CO · Η

O xd β 3 CO β <—t> H? JS

OH «—i & 0 Φ co m φ> j

N (0 fl β * g • rt β O> β H • hxd >> >> P P Ph

344 Φ 43 fl Η O P Φ n ω W-h 0 o

XD β fl t »β

ΟΌ hOP fl Φ Φ o β fl N

WHAT

CO β

P r — I £ 3½> β * - * • HXU

P P

3 Φ 43 K O Φ N w -h

O Ό >>

* Φ 43 β Φ Ό Ό Ο h h h h h h h h Ph Ph Ph Ph Ph Ph Ph Ph Ph P P P P P P

3 ja i h o Φ N CO P

300 96 48 48.5 29.8 8.9 0.8 12.1 31 1 92 68 45.1 33.7 7.2 0.9 12.6 322 96 80 37.9 36.8 4.8 0.8 19.8 342 99 89 29.4 36.6 5.3 1.0 27.7 361 98 94 31.1 30.9 2.4 0.9 34.7

Example 2

At the catalyst temperature of 350 ° C, isobutyl tert-butyl ether and water vapor air are fed to the reactor head with the catalyst specified in Example 1, so that mol. the ratio of isobutyl tert-butyl ether: oxygen: water vapor = 1: 1.1: 9.9 and the catalyst loading with isobutyl tert-butyl ether is 0.425 g. cm ^^. . h ^-1 .

The reaction product was condensed in a condenser and a separator. The conversion of isobutyl tert-butyl ether is 96.2%, the conversion of the formed isobutyl alcohol is 84% and the conversion of the formed isobutene is 23%. The selectivity of reacted isobutene to methacrolein is 32.1%, to methacrylic acid 15.9%, to acetone 36.0% and to carbon dioxide 14.6%

Example 3

Under otherwise similar conditions to Example 2, but at 380 ° C, the catalyst (mole ratio) isobutyl tert-butyl ether: oxygen: water vapor = 1: 1.5: 20.3 is fed to the catalyst under constant catalyst loading. isobutyl tert-butyl ether 0.373 g. ·)> '·

The conversion of isobutyl tert-butyl ether is 95-12%; conversion of isobutyl alcohol 77% and isobutene 18%. The selectivity of reacted isobutene to methacrolein is 30%, to methacrylic acid 18.2%, to acetone 43 $ and to carbon dioxide 8%.

Example 4

To 240 cm @ ^{5 of} distilled water, 28 g of tartaric acid, 5.5 g of antimony trichloride, 3.2 g of ferric nitrate, 1.9 g of copper nitrate, 7.0 g of cobalt nitrate and 0.3 g of titanium tetrachloride (solution I) are added. .).

A further solution (solution II) was prepared by dissolving 3.9 g of bismuth nitrate in dilute disubric acid.

A third solution (solution XII) is prepared by dissolving 12.8 g of ammonium heptamolybdate and 55 cm ⁵ of ammonium hydroxide with conc. 24 wt.

Gradual pouring of all three solutions gives a total catalyst solution having a pH value of 6 to 8, which is concentrated by evaporation into a paste at 70 to 80 ° C and dried for up to 12 hours at 120 ± 15 ° C and 1 to 3 hours at 160 ° C. Low: 14 ° C. This is followed by calcination in the temperature range of 170 to 430 ° C in a muffle furnace with gradual heating (from 170 ° C) - with a temperature rise of 40 to 80 ° C / h. The catalyst powder is then heated at a temperature of 420 to 440 ° C for 3 to 12 hours. Finally, it is mixed with kaolin in an amount of up to 6% by weight. and compressed into tablets, e.g., 1 x 3 mm cylindrical. 16 g of catalyst (Catalyst B) are obtained.

Example 5

In 200 cm @ 3 of water, 16 g of citric acid, 4.4 g of cobalt nitrate, 1.9 g of ferric nitrate, 1.4 g of nickel nitrate are dissolved. A solution of 2.4 g of bismuth nitrate in dilute nitric acid is then added and the pH of the solution is adjusted with 32 cm @ 3 of ammonium hydroxide with conc. 24 wt. to 7 to 8.

* Ί

In particular, a further solution is prepared by dissolving 10.2 g of ammonium heptamolybdate and 0.012 g of potassium hydroxide in 80 cm @ 3 of water.

Then the two solutions are decanted, 1.8 g of silica sol with conc. 30% wt. and the total solution is then concentrated into a paste at 60-80 ° C with vigorous stirring or may be dried at 130-160 ° C in a spray drier.

The paste is dried for 3 to 12 hours at 120 to 30 ° C and then for 1 to 3 hours at 150 to 170 ° C.

Both products are calcined and calcined with a programmed temperature increase: up to 2 h at 180 to 200 ° C from 0 to 2 h at 230 to 250 ° C; 0 to 2 h at 280 to 300 ° C; 0.5 to 2 h at

320-340 ° C; 0.5 to 5 h at 360 to 380 ° C; 0.5 to 2 h at 380 to 400 ° C and 3 to 12 h at 410 to 430 ° C.

The catalyst powder is then mixed with kaolin (3% by weight) and compressed into tablets which are optionally passed over a period of 2 to 24 hours at a temperature of 410 to 430 ° C. 11.2 g of catalyst (Catalyst C) are obtained.

Example 6

The procedure is similar to that of Example 4, except that solution I is prepared by dissolving 30 g of tartaric acid in 260 cm @ 3 of distilled water and adding 5.5 g of antimony trichloride, 3.2 g of ferric nitrate, 1.9 g of copper (II) nitrate, 5 g of cobalt (II) nitrate, 2 g of manganese (II) chloride, 0.3 g of thallium nitrate and 0.1 g of indium nitrate. 16.2 g of catalyst (Catalyst D) are obtained.

Example 7

Catalyst B prepared according to Example 4 or Catalyst C prepared according to Example 5 or Catalyst D prepared according to Example 6 can be added to the apparatus specified in Example 1 in an amount of 10 cm 2. An aqueous solution of tert-butyl alcohol is fed to the reactor head. with air and steam, so mol. ratio of oxygen: tert-butyl alcohol:

water: 1.4: 1: 14 and the catalyst loading with tert-butyl alcohol of 0.09 g. cm ^ _t . h ^_1 .

Depending on the type of catalyst and temperature, the following results are obtained (Table 2):

Table

Catalyst (type)

Reaction temperature ( ^C C)

Conversion of tert-butyl alcohol («)

Isobutene conversion («)

Selectivity (%) of reacted isobutene to:

si

VI

Λ o

<0

Φ i

Φ • and ω

Θ m

+>

Φ o

what

AND 310 96 76 55 30 8 0,5 6,5 (B) 340 99 92 45 39 7 1 8 C 341 99.5 93 46 38 6 1 8 D 340 99.6 94 45 40 7 1 7

Example 8

The procedure is as in Example 2, except that the catalyst C prepared according to Example 5 · Mol is used as the cleavage-oxidation catalyst. The ratio of isobutyl tert-butyl ether: oxygen: water vapor is 1. 2.1. 12.2 and the catalyst loading with isobutyl tert-butyl ether (at 380 ° C) reaches 0.3 g. cm ' ³ . h ^-1 .

Cat

The conversion of the formed isobutyl alcohol is 94%, the conversion of isobutyl tert-butyl ether is 99% and the conversion of the formed isobutene 38%. The selectivity of reacted isobutene to methacrolein is 41%, to methacrylic acid 22%, to acetone 26% and to carbon dioxide 11%.

Example 9. The procedure is similar to that of Example 8 except that a mixture of diisobutenes (21% 2,4,4-trimethyl-2-pentene and 79% 2,4,4-trimethyl-1-pentene) is used instead of isobutyl tert-butyl ether. at 0.3 g. ^c ®j _C g ^ · h. The conversion of diisobutenes reaches 98% and the selectivity of reacted isobutene to methacrolein 42% and to methacrylic acid 24%.

Claims (1)

Process for the continuous production of methacrolein and / or methacrylic acid by oxidation of tert-butyl organic compounds alone or together with isobutene, oxygen or oxygen-containing gas in the gas phase at 200 to 550 ° C, usually in the presence of water vapor and / or inert gas, with catalytic of a multi-component oxidation catalyst based on molybdenum, bismuth and iron, characterized in that the reaction is carried out with a catalyst of the type Mo Bi. Fe X.S1 _the K "0" ab cd EGF wherein Mo, Bi, Fe, Si, K and O represent molybdenum, bismuth, iron, silicon, potassium and oxygen, X is at least one of cobalt, antimony, nickel, titanium, manganese, me3, thallium, and indium, and a, b, c, d, e, f, g are atomic ratios of these elements, wherein a is 1 to 16, b is 0.1 to 3, c is 0.1 to 4, d is 0.1 to 8, e is 0.1 to 3> f is Q., 01 to 0.5 and g have a value that The tert-butyl alcohol, diisobutenes, tert-butyl alkyl ether of 2-5 carbon atoms and isobutanol are used as tert-butyl compounds.