DE1181192B - Process for the production of formaldehyde by the oxidation of methane with oxygen or air - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Boarding school Class: C 07 c

German class: 12 ο -7/01

Number: 1181192

File number: H 38357IV b / 12 ο

Filing date: January 12, 1960

Opening day: November 12, 1964

From the German Auslegeschrift 1 050 753 it is known for the production of formaldehyde methane with oxygen or air with the addition of small amounts of nitrogen monoxide in the presence of to oxidize finely divided solids as catalysts, which are whirled up in the reaction zone and the gas mixture emerging from the reaction zone immediately in a second fluidized bed zone to stabilize the formaldehyde formed. As a solid catalyst, the be ίο known processes preferably used pumice stone and a substance as fluidized material in the quenching zone with good heat transfer properties that affect the reaction mixture, in particular the reaction product, has no catalytic or oxidizing effect, for example silicon carbide, aluminum oxide or sand.

It has been found that the formaldehyde yield and thus the efficiency increases of the known method by leaps and bounds, if the reaction in a fluidized bed of Italian pumice is carried out at about 580-670 ° C and between the reaction zone and serving to quench the reaction mixture fluidized bed _zone: copper wire mesh is arranged.

The invention relates to a process for the production of formaldehyde by the oxidation of Methane with oxygen or air with the addition of small amounts of nitrogen monoxide in the presence of pumice stone as a catalyst at elevated temperature, this in finely divided form in the Reaction zone is whirled up and the gas mixture emerging from the reaction space for stabilization the formaldehyde formed is immediately quenched in a second fluidized bed. The procedure is characterized in that the reaction takes place in a fluidized bed from Italian Pumice stone performed at about 580 to about 670 ° C and between the reaction zone and the quenching zone the fluidized bed zone serving the reaction mixture arranges a copper wire mesh.

While compared to the known method only by using a copper mesh instead of a ceramic sieve, but without the use of Italian pumice stone, an increase in yield cannot be achieved and when using Italian pumice stone as a reaction catalyst, but only without using a copper mesh compared to the known method If a slight increase in the yield is achieved, there is a sudden increase in the yield compared to that of the known process, if such a process for the production of formaldehyde
by the oxidation of methane with oxygen
or air

Applicant:

Hüttenwerk Oberhausen Aktiengesellschaft,

Oberhausen (RhId.)

Named as inventor:

Werner Brocke, Essen,

Heinz Gertges, Kamp-Lintfort,

Dr. Olaf Heinze, Oberhausen (Rhld.) - Easter eld

probably Italian pumice stone used as a reaction catalyst as well as a copper mesh to separate the reaction zone from the fluidized bed zone serving to quench the reaction mixture will.

The process was carried out in an experimental reactor made of a heat-resistant porcelain tube, in its contact vortex zone, which is filled with pumice stone and heated to the reaction temperature by indirect electrical heating, the reaction mixture, a methane-air mixture in proportion 1: 5, was introduced.

The diameter of the porcelain pipe was 20 mm and the length of the heated pipe section was 115 mm. The reaction catalyst contained therein had a particle size of 4 mm and a displacement volume of 12 cm ³ . The Italian pumice stone used to carry out the method according to the invention came from northern Sicily and had the following composition:

SiO ₂ 69.15 Vo

AL ₂ O ₃ 14.50 «/ ·

Fe ₂ O _3. , 1.70%

CaO 0.76%

Na ₂ O 3.85%

K ₂ O 5.85%

TiO _2. ! 0.10%

MnO 0.11%

409 727/449

3 4

Mg traces The contact dwell time based on the free

Co trace volume of the reaction space was 0.35 sec

Cr .......... announce traces.

_N - "German pumice was used as the reaction catalyst

¹ pure _{5 stg} j _{n ν6πνεη £} } _ε (· _{; to} separate the reaction space

Pb traces _of that used to quench the reaction mixture

Ag traces serving fluidized bed zone was a copper wire

Ti traces ^ne tz with the properties described above

_Cu tracks turns.

„_ Ίο At a reaction temperature of 475 ° C was

* ^Η tracks _a F _ORMA id _e hydausbeute of 16.0 g formaldehyde

V traces _per normal cubic meter of methane achieved. At a

Mo gave traces of reaction temperature between 560 and 570 ° C

Loss on ignition 3.98% ^eme formaldehyde yield of 26.2 g and at

15 a reaction temperature between 660 and 680 ° C

In the comparative experiments, a pumice stone had a formaldehyde yield of 49.2 g formaldehyde of German origin used. per normal cubic meter of methane.

To separate the reaction vortex zone from the The test time was at all temperatures

this immediately following cooling vortex - between about 9Va and 10 minutes,
The bed was used to carry out the inventive 20 Compared to Experiment 1 in which a copper wire mesh with a mesh reaction zone was used to separate the process from the fluidized bed zone made of an alloy and used ^{to quench the reactivity of 64 / cm 2 and a wire thickness of 0.25 mm} 99.84% copper, 0.10% ceramic sieve was used, results in tin and traces of iron. For comparative experiments using a copper mesh for this purpose, a ceramic screen was used. 35 at the lower temperatures a slightly

As a fluidized material to quench the formed, improved formaldehyde yield, while with the formaldehyde in the cooling fluidized zone, the indirectly highest test temperatures, a somewhat poor formaldehyde yield was achieved with water due to a formaldehyde yield around the reaction tube,
put snake cooler was cooled, sand served

with a grain size of 0.1 mm and a test 3

displacement volume of 4 cm ³ . With further, here through the experimental reactor, a mixture

Experiments not listed were carried out as fluidized material of 6 liters of methane, 30 liters of air and 0.111 NO per hour Silicon carbide is also passed into the cooling vortex zone with one.

Grain size of 0.06 mm and aluminum oxide with The contact dwell time, based on the free

A grain size of 0.03 mm was used, with the volume of the reaction chamber being 0.35 seconds in 35, both cases the displacement volume being 4 cm ^3. Italian pumice was used as the reaction catalyst. The test results obtained in this way with the composition given above differ only marginally from the results used below to separate the reaction zone from the tests carried out with sand as a cooling fluid to quench the reaction mixture. 40 fluidized bed zone was a ceramic sieve ver

turns.

Experiment 1 at a reaction temperature of 470 ° C

a formaldehyde yield of 9.6 g formaldehyde

The experimental reactor produced a mixture of normal cubic meters of methane. With a reaction of 6 liters of methane per hour, 30 liters of air and 0.111 NO 45 tion temperature of 580 ° C, the formaldehyde (that is 0.3% NO, based on the throughput of yield 15.0 g, and at a reaction temperature the mixture ) directed. The contact dwell time, at 685 ° C, the formaldehyde yield was 75.4 g based on the free volume of the reaction space, formaldehyde per normal cubic meter of methane,
was 0.35 seconds. The trial time was around 10 in all cases

German pumice was used as the reaction catalyst for 50 minutes.

stone and to separate the reaction space from the opposite of experiment 1, in which the reaction

Cooling vortex zone uses a ceramic sieve. catalyst German pumice stone was used,

At a reaction temperature of 460 to 470 ° C., the use of Italian pumice stone resulted in a yield of 11.8 g of formaldehyde per reaction catalyst with the lower reaction standard cubic meters of methane. A slightly reduced reaction temperature and a higher reaction temperature of 570 to 575 ° C resulted in a slightly increased formaldehyde yield of 19.5 g per normal cubic formaldehyde yield,
meter of methane, and at a reaction temperature

a formaldehyde test 4 was carried out between 675 and 680 ° C

yield of 63.8 g of formaldehyde per normal cubic 60. The experimental reactor produced a mixture meters of methane achieved. of 6 liters of methane, 301 air and 0.111 NO per hour

The duration of the experiment was conducted at all temperatures.

between 9V2 and 10 minutes. The contact dwell time based on the free

_ΛΤ , _ volume of the reaction space, was 0.35 sec-

^{Announce attempt 2} 6 ₅ .

A mixture was produced by the experimental reactor. Italian pumice was used as the reaction catalyst.

of 61 methane per hour, 301 air and 0.11 NO stone with the properties described above and directed. to separate the reaction zone from the

quench the reaction mixture serving fluidized bed zone a copper wire mesh, as described above, used.

At a reaction temperature between 470 and 475 ° C., the yield was 16.7 g of formaldehyde achieved per normal cubic meter of methane. At a reaction temperature between 575 and 578 ° C was the formaldehyde yield is 149.2 g and at a reaction temperature between 670 and 685 ° C 188.0 g of formaldehyde per normal cubic meter of methane.

The test time was about 10 minutes in all cases.

By using both Italian pumice stone as a reaction catalyst and a copper wire mesh to separate the reaction zone from the one used to quench the reaction mixture In the fluidized bed zone, a formaldehyde yield is achieved which is higher even at low reaction temperatures than under the conditions of experiments 1, 2 and 3, while at higher reaction temperatures the formaldehyde yield jumped increases to values that are a multiple of those that would occur under the conditions of experiments 1, 2 and 3 could be achieved.

As can be seen from the above test descriptions, the known method and the Process according to the invention under completely identical experimental conditions with one another compared.

Claims (1)

Claim: Process for the production of formaldehyde by the oxidation of methane with oxygen or Air with the addition of small amounts of nitrogen monoxide in the presence of pumice stone as a catalyst at elevated temperature, the catalyst being whirled up in finely divided form in the reaction zone and that from the reaction space escaping gas mixture to stabilize the formed form aldehyde immediately in a second fluidized bed is quenched, characterized in that the Reaction in a fluidized bed made of Italian pumice stone at about 580 to about 670 ° C and between the reaction zone and that serving to quench the reaction mixture Fluidized bed zone arranges a copper wire mesh. Considered publications:
German patent specifications No. 756 487, 1050 752. 409 727/4 «11.64