DE1442950C - Process for the production of an oxidation catalyst - Google Patents

Description

X:

The invention relates to a process for the production of anhydride burns and "carbon dioxide and water of an oxidation catalyst is formed by treating. Furthermore, this oxidation reaction proceeds with silicon dioxide or silicon dioxide containing considerable heat generation. Therefore material with a soluble vanadium compound and the possibility of a catalyst for the production of Other catalyst or carrier components in phthalic anhydride by gas phase oxidation of aqueous medium, drying of the paste-like naphthalene obtained, variously investigated. Such a mixture as well as burning above the decomposition oxidation catalyst consisted of vanadium penteine temperature of the vanadium compound under conversion pyxide, which was on a carrier such as pumice stone , treatment in vanadium oxide, which is characterized by aluminum oxide or silica gel, was applied Approximately a crushing with, formation of a pasty mixture of mixed catalyst from vanadium oxide and caernew hydrated, whereby ma, n constituents, which Jiumsulfat contained in silica gel, for the production are escaped during the firing, supplemented the pasty of phthalic anhydride used. The oxidation mixture forms, burns and, if applicable, these conditions are as follows: reaction ^{temperature of renewed hydration, molding and firing again- 15 370 to 400 0} C, space velocity (SV) (liter fetches. Air / hour and catalyst I) of 1000 and Mixed

The French patent specification 1 213 190 relates to the speed of 36 to 38 g / m ^a . The yield

Manufacture of an oxidation catalyst. While - here and in the following, the

this is based on dissolved Kaliuinsilkat, weight ratio of product obtained to incorporated solid SiO _{2 is} understood according to the invention as the starting 20 set starting material, with a

material used. such a yield definition 100% are exceeded

In the Swiss patent 336 361 is in the can - of phthalic anhydride is 103%.

Connection with the production of an oxidation- The STY value (product g / hour and catalyst I)

Although the use of hydrated catalyst is 37.2. Despite this being described as excellent SiO ₂ , the catalyst used for hydration, its low volume reduces

Measures, however, consist of a constant speed of its industrial value,

borrowed wet milling processes. In a process for the production of male

In US Pat. No. 2,809,939, acid anhydride is used by gas phase oxidation, if

position of a fluidized bed catalyst for the oxidation of benzene as a raw material with air at a high organic compounds, starting from potassium 30 reaction temperature of 450 to 520 ° C in the gas

silicate. described, while it is oxidized phase according to the invention, to consider that the

around a fixed bed catalyst, starting from solid benzene completely via benzoquinone and maleic acid

SiO ₂ , acts. anhydride burns and carbon dioxide and water

While the German Auslegeschrift 1 097 962 a emerges. The oxidation reaction takes place under the Bemer method for the production of catalytic converters due to the generation of heat. Consequently Impregnation concerns, it is according to the invention was the possibility of a catalyst for around a process for the preparation of catalysts by gas phase preparation of maleic anhydride Hydration and shaping. Oxidation of benzene has been studied variously.

The German patent 613 259 relates to a process.

drive for the production of a catalyst support, from dium pentoxide, on a support such as pumice stone,

going from silicic acid, aluminum oxide or corundum mixed with sesquioxyden, carried, used,

containing materials, whereas according to the A catalyst is considered to be excellent

present invention silicon dioxide as raw material from a mixed catalyst of vanadium oxide and

material for the production of an oxidation catalyst molybdenum oxide supported on aluminum oxide

is used. 45 and which is used for the production of maleic acid

By none of the given literature references is the anhydride used. The oxidation conditions

The reactivation treatments according to the invention are as follows: reaction temperature from 470 to

described or suggested. 490 "C, space velocity from 3000 to 5000 and

The catalyst according to the invention has a mixing speed of 30 to 35 g / m ³ . From-

Excellent effect in the production of 50% maleic anhydride is about 75%.

way of phthalic anhydride by gas phase - The disadvantages of this catalyst are

oxidation of naphthalene or o-xylene, of maleic - that the yield is low and that its catalytic

acid anhydride by gas phase oxidation of benzene service life short, e.g. B. is about six months.

or of anihraquinone by gas phase oxidation ^ In the process for the production of anthra

by Anthra / cn. 55 is quinone by gas phase oxidation, if anthracene

(It is very general in a process for producing raw material for gas phase oxidation with air Positioning of phthalic anhydride by gas phase high reaction temperatures of 390 to 450 "C oxidation in lictracht that is used, for example, to consider that the application of naphthalene as a raw material for thrazen completely through anthraquinone, phthalic acid an- (iasphasenoxidation with an oxygen-containing gas fiohydride and maleic acid is burned and that at high reaction temperatures of 400 to 450 C carbon dioxide and water are formed. This oxidation that Naphthalene completely to form naphthoquinone, phthalic reaction takes place with remarkable heat evolution acid anhydride and maleic anhydride burned off. As a result, the possibility became one and that charcoal, oxide and water are formed or a catalyst for the production of anthraquinone various times in the gas phase oxidation of o-xylene as the crude phase oxidation of anthracene material with such a gas at high reac- examined. Such an oxidation catalyst betionsleinperaturen from 450 to 480 "C the o-xylene is composed of vanadium pentoxide, supported entirely on a support to phthalic anhydride and maleic acid substances such as pumice stone or aluminum oxide. An as

An excellent catalyst consists of a carrier component that can be used as well as

Mixed catalyst of vanadium pentoxide, potassium- the essential component silicon dioxide, z. B.

sulfate and iron oxide and is worn on pumice stone. Metal oxide, such as magnesium oxide, aluminum oxide

In the production of anlhraquinone, the oxy- or titanium oxide and the like are inorganic compounds,

dation conditions follow: reaction temperature 5 such as sulfates, phosphates or carbides, or natural

from 380 to 395 ° C, space velocity of 1500 products, such as diatomaceous earth, Japanese acid clay,

and mixing speed of 21 g / m ³ . The yield listed pumice stone or refractory hyalite. When

of anthraquinone is about 95 to 97%. The post-catalyst ingredients will be used as the main component

Parts of this catalyst consist in that yield a vanadium compound and as an auxiliary component

and STY value are low and that the purity of the io to improve the catalyst is a compound

Raw material at least 97% ^s> n must. Of potassium, calcium, titanium, chromium, manganese, iron,

Furthermore, each of the cobalt, nickel, copper, zinc, molybdenum, palladium, and catalysts listed above has such a high refractive index that it can hardly be described as silver, cadmium, tin, cerium or platinum or a tough, solid catalyst. organic salt, such as / the sulfate or phosphate, Under the term refractive index used here is used 15, which are added as effective ingredients the ratio (percentage) of the number of broken ones. ... ·, '...
Catalyst test samples to the total number of tested The catalyst prepared according to the invention beProben to understand if an impact test so sits not only a strong activity and is solid, that a shaped catalyst is carried out but there will be a yield and a center of a glass tube of 25 cm Height and 12mm 20 purity of the reaction product is achieved, which is brought higher diameter and a metal weight than by any catalyst which has not been activated in the above manner of 5 g from a height of 25 cm on the catalyst. Especially to be dropped. mention is that the life of the catalyst

These known, usual disadvantages are due to the fact that it is long and that the STY value is very high.

the highly active and solid catalysts according to the invention. The following examples serve to further explain

Sator overcome if it is made so that the invention sion.
SiHciumdioxyd as raw material is hydrated too

a hydrate (SiO ₂ · / 1H ₂ O, where / 1 is the number 1 or 2 B cis ρ ie 1 1
means), then a vanadium compound to that

Hydrate added or the silica hydrated 30 5.35 g vanadium pentoxide were in 33 ecm one

is suspended while the vanadium compound is added solution with 16% sulfuric acid. While

is, resulting in a pasty mixture that the suspension was heated to 60 to 70 "C,

optionally other carriers and / or catalysis 3 liters of sulfur dioxide were blown in to a

Sator ingredients are added to the pasty mixture to give vanadyl sulfuric acid solution. To this

and the mixture above the decomposition temperature 35 solution, 50 g of silica gel, 25 g of potassium

the vanadium compound, in which the compound sulfate, 25 g ammonium sulfate, 0.5 g potassium phosphate

manure is converted into vanadium oxide, burned and added. The mixture was mixed thoroughly

Furthermore, in order to increase the catalytic activity, and 20 ecm of water were added to the mixture. The

the possibly escaping constituents in the mixture was kneaded until it was pasty, and to

If necessary, add 40 tablets of 5 mm in diameter and 5 mm in length to the burned mixture

and the silica in the mixture is formed hydrated. The tablets were dried and were

is, so that the mixture is pasty and the pasty is ^{burned at 360 0} C for 12 hours, so that the

Mixture is then shaped and fired and vanadyl sulfate is converted into vanadium oxide,

if necessary repeatedly hydrated, shaped and possessed the tablets thus obtained

is burned. 45 already has catalytic activity. However, were

As silicon dioxide, either silicon dioxide is used according to the invention to specifically target this catalyst themselves or materials which deactivate silicon dioxide, the tablets on 100 meshes of 2.5 cm each hold, for example, powdered carrier substances, naturally broken, 5 g silica gel and 10 g ammonium gel Carriers or shaped carriers use sulfate to ground 100 g of the broken catalyst. As a vanadium compound, a compound 50 is used as a supplement to those listed above used, which gives vanadium oxide on burning, z. B. combustion escaped constituents added that Vanadium pentoxide or ammonium metavanadate. Mixture well mixed, 15 ecm and 55 ecm one

To increase the catalytic activity, the solution of 16% sulfuric acid is added to the mixture

Fired product continues to be hydrated or added, the mixture kneaded to get the silicon

individual cases repeatedly hydrated, then formed and then hydrated 55 dioxide of the carrier component

burned, the preparation of the hydrate being made pasty and in tablets of 5 mm diameter

of the invention, e.g. B. processed in a heated and pressed knife and 5 mm length. The tablets

State by adding water to the powder of the were dried and then at 360 "C during

Catalyst is carried out, so that the silicon is burned for 12 hours, with an activated catalyst

Dioxide can be hydrated. If in this case 60 sator resulted.

an organic or inorganic acid as hydra- 1 liter of this activated catalyst was in a

The accelerator used is the hydration reaction tube, which is immersed in a molten salt bath

ization accelerates and can be given even at normal pressure was immersed. If a gas mixture with.

be performed. As usable inorganic an amount of 40.6 g of crude naphthalene with a

Acids are z. B. sulfuric acid, hydrochloric acid, phosphorus 65 purity of 96% per m * air in the gas phase with

acid and the like. As usable organic a space velocity of 1960 in the cataly-

Acids are z. B. low fatty acids or oxalic acid, satorschicht at a temperature of 365 ° C of the salt.

Maleic acid or succinic acid listed. The bath was oxidized to give crude phthalic acid

anhydride with a purity of 97.4% in one out anhydride with a purity of 96.2% in one

prey of 103.2% (STY 80.0). Yield of 101.8% (STY 81.9).

For comparison with gas phase oxidation under For comparison with gas phase oxidation under

Use of the above, non-use of the above non-active

activated catalyst, 1 liter of the non-activated catalyst became 1 liter of the non-activated

fourth catalyst placed in a reaction tube, catalyst placed in a reaction tube, which in

which was immersed in a molten salt bath, immersed in a molten salt bath, and

and a mixed gas in an amount of 36.6 g, a mixed gas in an amount of 36.2 g crude

crude naphthalene with a purity of 96% per m ³ naphthalene with a purity of 96% per m ^{3 of} air in

Air in the gas phase with a space velocity io of the gas phase with a space velocity of

of 1000 in the catalyst layer at a temperature of 1000 in the catalyst layer at a temperature

Oxidized at 365 ° C in the salt bath. With the exception of "365 ° C the salt bath is oxidized, being crude

The space velocity is essentially correct phthalic anhydride with a purity of 94.6%

all conditions with those obtained when using the active in a yield of 99.6% (STY 34.1)

fourth catalyst. The application of a 15 was made.

higher space velocity (around 1960) at B ice η ie 1 3
non-activated catalyst is forbidden here and in

the following examples, since then a partial 22.0 g vanadium pentoxide were in 40 ecm one

combustion of the material suspended with an increase in the temperature solution with 16% sulfuric acid. While

door takes place what to melt the in the catalyst so the suspension was heated to 60 to 70 ° C,

containing vanadins and thus the loss of 13 liters of sulfur dioxide were blown in to reduce a

Catalyst activity leads. For this reason, a vanadyl sulfuric acid solution should be prepared. To this

an exact adjustment of this reaction condition solution was 10 g of silica gel, 0.60 g of potassium

movement (namely space velocity) not possible; sulfate and 114 g of aluminum oxide added and that

instead, mixing thoroughly using the non-mixture. 50 ecm of water were

activated catalyst added the optimal conditions to the mixture. The mixture became again

respected with regard to its reaction. The heated in a to 60 ³ C and then kneaded well to

Yield of 101% (STY 35.4) obtained raw making it pasty while letting it cool

Phthalic anhydride was 95.4% pure. would. The pasty mixture was in tablets of

_n . . . 30 4 mm diameter and 4 mm length processed. the

Example 1 Tablets were dried and then at 355 ° C

6.88 g ammonium metavanadate, 50 g silica gel, calcined for 12 hours, whereby the vanadyl

25 g of potassium sulfate, 25 g of ammonium sulfate and 0.5 g of sulfate was converted into vanadium oxide. The tablets

Phosphoric acid were combined and found- by itself showed catalytic activity. To however

Mixed up. According to the invention, this non-activated catalyst was added to this mixture

a solution of 16% sulfuric acid and 20 ecm specifically to activate the tablets

Water added. The mixture was broken to produce 200 meshes each 2.54 cm, 40 ecm one

well kneaded into a paste. The pasty mixture was added to a solution of 16% sulfuric acid and then

to tablets 5 mm in diameter and 5 mm in length 50 ecm of water to 100 g of the broken catalyst

processed. The tablets were dried and added. The mixture was ^{heated to 6O 0} C and

then baked at 360 ° C for 24 hours, then kneaded well while cooling

the ammonium metavanadate to the vanadium oxide to hydrate the silicon dioxide of the carrier component

was convicted. The tablets were already self-sizing. It was then made into a paste and added to

a catalytic activity. However, tablets were made of 4 mm in diameter and 3 mm in length

according to the invention the non-activated catalyst 45 formed, whereupon the tablets are dried and then

to activate specifically, the tablets were fired on 100 meshes at 355 ° C for 12 hours,

each 2.54 cm broken and 0.62 g ammonium-m-vana- which resulted in an activated catalyst,

dat, 5 g of silica gel and 12 g of ammonium sulfate are good When a liter of this activated catalyst in a

mixed with 100 g of the broken catalyst, reaction tube, which is in a molten salt

around which 50 bath was immersed during the above-mentioned firing, was given and a mixed gas

to replace escaped components, and then with an amount of 41.6 g of o-xylene per m ^{a of} air in the

70 ecm of water was added to the mixture, the Ge gas phase with a space velocity of 2500 in

mixed at a temperature of 155 ° C and one of the catalyst layer at a temperature of

Pressure of 5 kg / cm ^{2 was} oxidized well by 410 ⁰ C of the salt bath for 10 hours, the result was crude

kneaded to form the silicon dioxide of the carrier component- 55 phthalic anhydride with a purity of 96.2%

partly to hydrate, then processed to a paste containing 2.2% maleic anhydride in

'and tablets with a diameter of 5 mm and 5 mm with a bulge of 98.4% (STY 98.4).

Shaped length. The tablets were dried and for comparison with the gas phase oxidation under \

then fired at 360 "C for 12 hours, using the non-active ones listed above

was obtained by the activated catalyst. 6o fourth catalyst was 1 liter of the non-aclivicrtcn f

1 liter of this activated catalyst was in a catalyst in a reaction tube, which is in an I.

Reaction tube, which was immersed in a molten salt ·· molten salt bath, and f

bath was immersed, given and a gas mixture, a mixed gas with an amount of 32.4 g of o-xylene per m ^3,. |

with an amount of 41.4 g of crude naphthalene with air in the gas phase at a space velocity of |

a purity of 96% per m clwa ^a air in the gas 65 of 1540 in the catalyst layer at a tem- |

phase is oxidized at a space velocity of 2020 in the peralur of 410 "C of the salt bath, whereby

Katalorschichl at a temperature of 365 "C crude phthalic anhydride with a purity of

of the saline bath is oxidized, with crude phthalic acid - about 94.2% with a content of 4.2% maleic acid -

anhydride was obtained in a yield of 89.6% (STY 42.1). .

Example 4

7.5 g of vanadium pentoxide were heated and dissolved in 75 ecm of a solution with 26.4% oxalic acid, resulting in a vanadyl-oxalic acid solution. On the other hand, 3.5 g of ammonium phosphomolybdate was heated and dissolved in 75 ml of a solution containing 25.2% oxalic acid, thereby giving a solution of the ammonium phosphomolybdate in oxalic acid. This solution and the above-mentioned vanadyl oxalic acid solution were mixed together. 5 g of silica gel and 120 g of aluminum oxide were added to this mixed solution. The mixture was mixed very well and kneaded well at 60 ° C. so that it became pasty. The pasty mixture was processed into tablets 5 mm in diameter and 5 mm in length. The tablets were dried and then calcined at 400 ⁰ C for 10 hours, with the vanadium oxide in Yanadyloxalsäure was transferred. The tablets already showed catalytic activity. However, in order to specifically activate this non-activated catalyst according to the invention, the tablets were broken to 200 meshes each 2.54 cm, 100 ecm of a solution with 5% oxalic acid were added to 100 g of the broken catalyst, the mixture which was heated ^{to 60 ° C} , kneaded well to hydrate the silica of the carrier component. It was made into paste, and tablets of 5 mm in diameter and 5 mm in length were molded therefrom, which were dried and then calcined at 400 ° C. for 10 hours, thereby giving an activated catalyst.

When 1 liter of this activated catalyst was poured into a reaction tube immersed in a molten salt bath and a gas with an amount of 32.4 g benzene per m * air in the gas phase at a space velocity of 3200 in the Catalyst layer was oxidized at a temperature of 450 ° C. of the salt bath, maleic anhydride was obtained in a yield of 89.6% (STY 92.9).

For comparison with the gas phase oxidation using the non-activated catalyst listed above, 1 liter of the non-activated catalyst was placed in a reaction tube which was immersed in a molten salt bath and a gas mixture with an amount of 28.0 g benzene per m »air in the Gas phase oxidized with a space velocity of 2700 in the catalyst ^{layer at a temperature of 450 0} C of the salt bath, maleic anhydride with a yield of 82.4% (STY 62.3) being obtained.

Example p

10.5 g of vanadium pentoxide was dissolved in 20 cc of a solution containing 16% sulfuric acid suspended 6 liters of sulfur dioxide was blown into the suspension while it was heated to 60 to 70 ⁰ C, to prepare a vanadyl-sulfuric acid solution or a solution A. 0.282 g of ferric chloride was dissolved in 10 ecm of water, resulting in solution B. In addition, 0.70 g of potassium sulfate was dissolved in 10 ecm of water, resulting in solution C. To the mixed solution of solutions A, B and C were added 10 g of silica gel and 114 g of aluminum oxide. The mixture was mixed thoroughly and further 30 ecm of water was added to the mixture. The mixture was ^{heated again to 60 °} C., then kneaded well while cooling and processed into tablets 4 mm in diameter and 4 mm in length. The tablets were dried and then calcined at 330 ⁰ C during Yl hours so that the vanadyl sulfate was transferred to Vanadinoxyd. The tablets themselves already had catalytic activity. However, according to the invention, these were not activated

allowed to activate ίο catalyst specifically, the tablets broken to 200 stitches per 2.54 cm, 50 cc of a solution containing 5% hydrochloric acid and 20 cc of water to 100 g of the crushed catalyst was added, the mixture to 6O ⁰ C is heated, then allowed to cool and thoroughly kneaded to hydrate the silica of the catalyst component. It was a paste was made and tablets 4 mm in diameter and 4 mm in length were formed, which were dried and then baked at 330 ° C for 2 hours

ao, whereby the activated catalyst was obtained.

When 1 liter of this activated catalyst was placed in a reaction tube immersed in a molten salt bath and a gas

The mixture with an amount of 31.6 g of raw anthracene with a purity of about 92.0% per m * of air in the Gas phase at a space velocity of 3200 in the catalyst layer at a temperature of 395 ° C of the salt bath was oxidized, resulted in crude

Anthraquinone with a purity of 94.6% in one Yield of 98.6% (STY 94.3), which is 4.2% Phthalic anhydride, 0.2% maleic anhydride and

Contained traces of unreacted substance.

For comparison with the gas phase oxidation below

Using the non-activated catalyst listed above, 1 liter of the non-activated catalyst was placed in a reaction tube which was immersed in a molten salt bath, and a gas mixture with an amount of 26.0 g of anthracene with a purity of about 98% J ^e m ^a air in the gas phase at a space velocity of 2200 in the catalyst layer at a temperature of 395 ° C of the salt bath oxidizes, with crude anthraquinone with a purity of 90.4% in a yield of 94.2% (STY 48.7) was obtained, which is 7.2% phthalic anhydride, 0.6% maleic anhydride and 1.2% unreacted substance contained

Claims (1)

Claim: Process for the preparation of an oxidizing catalyst by treating silicon dioxide or silica-containing material with a soluble vanadium compound and others Catalyst or carrier components in an aqueous medium, drying the pasty mixture obtained and burning above the decomposition temperature of the vanadium compound with conversion to vanadium oxide, thereby indicates that the shaped firing material obtained in this way is rehydrated after comminution to form a pasty mixture, where ingredients that have escaped from the burning sensation are added to the pasty mixture «5 forms, burns and, if necessary, this again Performs hydrating, sculpting and burning repeatedly 209 Ä32730