DE1419672B - Use of shaped supported catalysts for detoxification and deodorization of industrial and heating exhaust gases - Google Patents

Description

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The invention relates to the use of Trager- with metal oxide located thereon, for. B. Vanadium catalysts to detoxify and deodorize pentoxide

Industrial and heating exhaust gases, which in particular is the same in the German patent specification

containing organic compounds and carbon oxide, 630 414 a catalyst for the same purpose

through afterburning. 5 known, the aluminum oxide-rich carrier material

In numerous technical processes there is one that is activated by metal salts
The task of removing organic substances by means of warmth. The two processes mentioned relate to the effect of removing products, whereby it ultimately relates to the catalytic afterburning of destination, sublimation or partially incinerated car exhaust gases contain pyrolyzation, which occurs during industrial pyrolysis, carbonization or also cracking of the organic, carbonization or cracking processes , Pp. 20 and 21, supplement to "Applied objects, not only the solvent components, chemistry"), but the concentration of such separators, including the lower-boiling components of the film, is far lower here than in the informer and the other paint additives with more dust emissions

or less pronounced decomposition, so that the exhaust gases

from a paint drying or baking oven a variety of analyzers for the oxidative detoxification of industrial waste

of fission products, condensation and polymeriza-

tion products, for example phenols, formaldehyde 20 lysatorsystemen can be derived, which

and polymeric formaldehyde, ketones, isocyanates and especially for the detoxification of car exhaust fumes.

contain a wide variety of alcohols. Apart from poses are

of the fact that these waste products pass through

the pipelines react with one another and solid - predominantly the oxidation of unburned carbon

separations can form which the pipelines are supposed to carry 25 hydrogen and carbon monoxide,

clog more or less quickly, such waste must be catalysts for cleaning industrial

gases are extremely harmful to health, especially exhaust gases, many of them often heavy

special because of their carbon oxide content also toxic oxidizable organic compounds, z. B. Pheno-

and in some cases represent an intolerable gel or polynuclear aromatic compound, which moreover m

odor pollution. 30 high concentrations can occur, with

Similar circumstances also exist where conditions have to be implemented which differ from the

Molded parts made of metal or oxides with the addition of lytic afterburning of car exhaust

Binding agents are pressed and the binding agent conditions are known to differ greatly,

removed prior to further processing of the compacts. Although the present invention is based on one

must become. Such binders, which are known, for example, from German patent 630 414

consist of oils, synthetic resins, adhesives, the th type of catalyst will also create them

"Burned off" before sintering This also creates the conditions under which it is difficult to

if foul-smelling and sometimes poisonous exhaust gases. Metal-coated supported catalytic converters for post

can be used in many heating processes, especially in the case of oil-fired combustion of industrial exhaust gases,

gen, the incomplete combustion leads to the formation 40 These basically exist then that with such

of soot-containing waste products that have a strong loading

represent strain. its present state of manufacture, rather

For this reason, a thorough, technical, rather in the form of forms of certain special

nically simple and reliable detoxification and desofic surface and certain pore volume

Doring of such exhaust gases is an urgent concern of the 45 used

Technique is It is known for this purpose, the invention therefore relates to the use of a catalytic post-combustion gases to lower molded supported catalysts whose transmitter throw Thus, from German Patent Specification 558,940 least superficial strength of η- or γ- alumina, a method known, in which mercaptans by means of a BET surface area between 100 and 300 m ² / g of an unspecified, exclusively composed of 50 and a pore volume of 0.2 to 0.5 ml / g, ent-CuO catalyst in the presence of corresponding to a pore diameter of 20 to 300 Å oxygen should be burned. Insofar as there are catalysts on the surfaces of which vanadium oxide, chrome lysers, precious metals are used, e.g. platinum oxide, bismuth oxide, copper oxide, cobalt oxide, silver or palladium, these contacts are dangerous in many practical cases, nickel oxide, manganese oxide or iron oxide a premature 55 0.1 to 10 percent by weight individually or in a mixture term poisoning by impurities are applied, at temperatures between 200 and so that their service life leaves something to be desired 800 ⁰ C, for afterburning industrial and and frequent regeneration or more frequent heating exhaust gases, which are harmful and / or odor-replacing the expensive material necessary, contain annoying flammable compounds
can 60 According to a preferred embodiment of the

There are already a number of catalysts to be found as carriers inert substances, such as aluminum requirement prevent the oxidation of car exhaust fumes, which are associated with aluminum oxide, beat has been used

So from the German Auslegeschrift 1074 325 The catalyst supports can, for example, m shape

known to remove hydrocarbons 65 from compacts with a diameter of about

from exhaust gases from internal combustion engines used by cataly- 1.5 mm and a length of 5 to 10 mm

table afterburning to use catalysts,

The carrier for the heavy metal oxide does not have to be in

Claims (3)

3 4 all of them are made of aluminum oxide; they go into action without the effect being able to subside rather, in turn, be composed of the totality of the catalytic post-combustion unit a core made of any material, including inert material, could be tested. The exhaust fumes came out and a coating of the active alumina. after the contact bed colorless and odorless from, in For example, for the purposes of the invention, the pipelines were not settled Aluminum hydrosilicates that are delivered with a through. On the other hand, the catalytic post-thermal process became odei chemical decomposition aluminum combustion unit not used, so came out of the oxide-forming aluminum compound impregnates gas discharge pipes with foul-smelling, blue-gray mist are proven to be suitable. out For the contact to work properly, io B e ι sd ι e 1 2
it is essential that in the method according to the invention the contact bed at a temperature of at least Under similar conditions, the exhaust gases were kept 200 ⁰ C, but that on the other hand, detoxifies the tem- of a paint baking oven and does not exceed 800 ⁰ C desodoperatur. As with the burned. It was used as a carrier the same aluminum oxide voltage is produced in contact with heat, provided that the 15 is used, as described in the example! the contact exhaust gases are not too diluted, but an additional domestic mixture did not require the following composition; with very dilute exhaust gases - ,. . _{i1im . ^ ₁₀ ,
However, it may be necessary to place the chromium oxide contact bed on an aluminum support. .. 43% to be heated at least alternately in order to achieve the optimal Janadmmoxid au aluminum support. ... 24 ₀ temperature of 800 ⁰ C by means of passing air through the oxide content was all contact components or other Verdunnungs- or cooling gases, except for silver oxide at 5%, based on the weight can be prevented by the contact bed. An excess of 25 alumina support and oxide. The silver-containing device at the stated temperature turned into an in-contact component containing 1.5% Ag ₂ O and resulted in activation of the contact. Direction of gas passage on the mixed Appropriately, the remaining contact components during post-incineration are arranged as the uppermost layer in the contact, which can be felt in the contact. The temperature of the furnace exhaust gases was, as is known, through a heat exchange 30 on entry into the contact ^{bed 450 0} C, which made the concentration usable, e.g. through such a tration of flammable components was so high that heat exchange the air for a lacquer drying furnace or in a contact bed Temperature increase occurred The stoving furnace had to be preheated. The invention will be kept at 650 ^° C. on the outlet side with the aid of the following examples, will be explained further. 35 The zyhnderformig arranged contact bed had a freely flowable diameter of 30 cm. Example 1 61 catalysts were used at a throughput of about 20 m ³ gas / hour used during a permanent For the afterburning of exhaust gases from an experiment of 11 weeks, this contact-burning furnace, in which the compacts were freed from a binder consisting of oil and 40 beds, about 900 kg of solvent and dextrin paint residue, were completely burned. After the dismantling, no sedimentation whatsoever was used in the catalyst of the following assemblies in the pipes after the contact bed. At the end of the test period, vanadium oxide on aluminum oxide support 70%, ^no decrease in the catalyst efficiency, was discernible. Copper oxide on aluminum oxide support 6.5% ^{45 The} gases escaping without purification smelled cobalt oxide on aluminum oxide support. 6.5% phenol and intensively for burning caused in bismuth oxide on Aluminiumox.dtrager 7%? En ^{en Au and} S ^'m nasopharyngeal space In addition, nickel oxide on alumina exchanger 5% they caused in the vicinity of the exit point a manganese oxide on alumina exchanger 5% Air turbidity The one from the post-combustion unit 50 escaping gases were practically nefarious The concentrations are for vanadium, air remained clear, the phenol content was also increased Copper and cobalt oxides each between 6 and 8%> checked for trace analysis. For this purpose a befur the remaining 0.8%, based on the total amount of gas through a test tube with a sum of oxide and aluminum oxide. Solution of alcohol borax and 2,6-dichloroquinone _{The Al 2} O ₃ used as the carrier had passed a BET- 55 chloride imide, the phenol still in a concentration surface of 180 m ² / g, em pore volume of tration 1 20 million indicated by blue coloration 0.45 ml / g and consisted of extruded parts of about (HoubenWeyl "Msthoden der organic 1.5 mm diameter and 5 to 10 mm long fur chemistry", Vol. 2, S 369, Gsorg Thiems Verlag, Stuttgart hourly throughput of about 400 m ³ exhaust gas gart, 1952) used 301 catalyst from the contact were coupled to the gas withdrawing gas bed 60 via no Piienol nacheintnttsseite at an average temperature of 200 ⁰ C pointed be, while gas samples before dsr con- and on the gas outlet side on such a clock unit a momentary, deep Blue color was kept at 300 ^° C. The contact bed had one effect Height of 12 cm and a cross section of 0.25 m *. Claims. Since the concentration of combustible substances is 65 strongly fluctuated depending on the furnace operation, 1 use of shaped support catalysis a partial additional heating of the contact bed was gates, the support of which was at least superficially made of η- necessary A test unit was 18 Wo- or γ- aluminum oxide with a BET surface between 100 and 300 m ² / g ^{un (} i a pore volume of 0.2 to 0.5 ml / g, corresponding to a pore diameter of 20 to 300 Å, exist on the surfaces of vanadium oxide, chromium oxide, bismuth oxide, copper oxide, cobalt oxide, silver oxide , Nickel oxide, manganese oxide or iron oxide of 0.1 to 10 percent by weight are applied individually or in a mixture, at temperatures between 200 and 800 ⁰ C for the afterburning of industrial and heating exhaust gases that contain harmful and / or ao odorous combustible compounds 2 Use of supported catalysts according to claim 1 with inert substances, such as aluminum hydrosiphons, which are coated with aluminum oxide, as a carrier 3 Use of supported catalysts according to claim 1 or 2 from compacts with a Diameter of about 1.5 mm and a length of 5 to 10 mm