DE1667073A1 - Improved catalyst for reforming hydrocarbons with water vapor - Google Patents

Description

Patent registration

for

The Gas Council, 4-5 G-rosvenor Place, London S.W. 1, England

"concerning

Improved catalyst for reforming hydrocarbons with "" water vapor

The invention relates to catalysts for reforming of hydrocarbons with water vapor and processes for their production.

British Patent 1,039,206 describes and claims Catalyst masses effective in reforming hydrocarbons with steam; these Catalysts contain «(1) nickel oxide, (2) triurane octoxide U-iOg, (3) potassium hydroxide, potassium oxide and / or potassium carbonate, and (4) a carrier containing alumina or alumina and magnesia.

109822/1841

British patent application 26 946/66 (German patent application N 30 709 IVa / i2q (our reference P-3156-1)) describes and claims a substantially halogen-free catalyst mass, which is used in the reforming of hydrocarbons in Presence of water vapor at elevated temperature to generate gas mixtures containing hydrogen and carbon oxides, is effective? this catalyst mass contains: (1) nickel, nickel, ^ oxide and / or a precursor for this, (2) Uranosouranioxyd U ^ Og and / or uranium trioxide and / or a precursor therefor and (3) a Carrier containing aluminum oxide and / or an alkaline earth oxide.

Both property rights describe and claim procedures for the production of these catalysts.

It has now been found that a catalyst of the type mentioned with the advantageous properties mentioned above can be prepared by going to the catalyst support before ™ Adding the uranium and nickel compounds a small amount Adding alkali compounds.

According to the present invention is therefore a method for Production of a catalyst mass for the reforming of Hydrocarbons provided with water vapor, the Catalyst mass contains «(1) nickel oxide and / or a precursor for this, optionally together with elemental nickel, (2) uranium aouranoxide. and / or uranium trioxide and / or a precursor

10 9 8 2 2/18 ^ 1

" ³ " ■ -T667073

for uranium dioxide and / or uranium trioxide, (3) a catalyst carrier containing aluminum oxide and / or alkaline earth metal oxide and (4) an alkali compound other than halogen-containing in an amount less than $ 0.5 »expressed as weight of the alkali metal, based on the weight of the total catalyst mass this process is characterized by the deposition of the alkali compound and / or a precursor for this purpose, as defined above, on the catalyst support before the addition of the uranium and nickel compounds to the carrier.

Under the term Uranosouranioxyd used here is that Mischoxyd U, Og meant that in some publications also known as triuranoctaoxide (zj, "Handbook for Chemical Society Authors ", page 22, published by the Chemical Society 1960).

The term "pre-stage" as used herein in relation to a Alkali compound refers to all other alkali compounds except halogen-containing, which either under the action from heat or under the conditions of deformation of hydrocarbons with water vapor into the alkali compound decompose, for which they represent a preliminary stage.

The combination of the alkali compound with the catalyst support is achieved by deposition of the compound or its precursor carried out on the surface of the support * A deposition is expediently achieved by the catalyst support

10 9822/1841

"" "ru-67073-

treated with an aqueous solution of the alkali compound or its precursor.

The temperature at which the deposition is carried out should preferably be 40 to 150 ⁰ G, ₌ 60 to 100 ⁰ G, and more preferably 75 to 85 G ^0. If necessary, the process can be followed by washing a carrier φ impregnated in this way with water. Another embodiment of this last procedure consists in treating the carrier impregnated with an alkali compound with a further solution from which one or more other active compounds of the catalyst mass are deposited on the catalyst carrier. For example, alumina in spherical or granular form can be immersed in an aqueous solution of the alkali compound, for example potassium nitrate or acetate or hydroxide, then taken out, drained off and placed in a solution of mixed uranium and nickel salts, 65B. Uranium and nickel nitrates and / or acetates or other carboxylates. When the impregnated alumina is transferred into a second solution, part of the alkali compound is leached from the surface of the alumina into the second solution, the required amount of alkali compound remaining on the alumina surface.

When the alkali compound on the surface of the catalyst support is depressed, the production of the catalog

109822/184

lysatormasses according to the present invention take place in several ways ¹ , some of which are described in British patent application 26 946/66 (German patent application N 30 709 IVa / i2g (our reference; P-3156-1) ί.

As stated earlier, after the deposition of the Alkali compound with solutions of nickel and uranium salts, either together or individually, which causes the deposition of the active components on the catalyst. The uranium and nickel salts must be those that either during calcining or under reforming conditions decompose with steam to metal oxides or elemental nickel. If necessary, the deposition follows in Solution calcining to produce the metal oxides. Suitable salts for such a separation are nitrates, Carboxylates, preferably acetates, which decompose to oxides under controlled conditions, and highly active catalysts result, as it is in the British patent specification 27 579/66 (German patent application α 50'432 iVa / 12g (our Character * P-3157-1)) is bad. According to another embodiment the uranium can be present in the solution as ammonium diuranate. The process can comprise one or more stages, in which the uranium oxide present in a series of one or subjected to several oxidation-Hödüktionäzykien under controlled temperature conditions. This way of working causes increases the activity of the catalyst. This procedure is

10902 2/1841

Subject of earlier British application 27 578/66 . (■ German patent application G 50 433 IVa / i2g, our reference: P-3158-1).

■ It is preferred that the method according to the invention The catalyst carrier used is alumina and that the alkali compound is a compound of lithium or potassium. The alkali compound is preferably in the form of the oxide or a preliminary stage for this. The preliminary stages include Hydroxides, nitrates * Acetates, trusses and tartrates, carbonates or bicarbonates, although many other "soluble metal salts" can also be used. The alkali compounds however, must not contain halogen * and the process of Invention does not include a process using alkali halogen salts contains.

While a concentration of less than 0.5 ^ alkali compounds is permissible, it is preferred that the concentration of between 0.05 and 0.3 fi, or more preferably between 0.1 and 0.2 $> is, all percentages are expressed as the amount of alkali metal present, based on the total weight of the catalyst *

A disadvantage of using the alkali compound in catalysts for reforming with steam is blocking of the active sites on the catalysts. By manufacturing

103822/1841

" ⁷ " iS67ö73

of a catalyst according to the present invention are the reactive sites or a substantial part of them are released for reforming with steam. At the same time, the presence of alkali compounds helps to prevent the deposition of carbon on the surface of the catalyst, with such deposition as is believed to result from the residual acidity of the alumina surface or its parts. As a result, the service life will be of the catalyst when made according to the process of the present invention.

Another benefit of using small ones Amounts of alkali compounds on the support surface according to the present invention is that reduced There is a tendency for the alkali compound to evaporate and in to migrate other parts of the reaction system. Experience has shown that evaporation or migration of the alkali compounds in other parts of the reaction system give rise to serious difficulties in practicing the Reforming process can give. The influence of such Connections at temperatures such as those applied to stainless steel vessels and components of the system is, is or can in many cases give rise to increased stress corrosion of stainless steel.

To make the method of the present invention more understandable To make, an embodiment of the method will now be described.

109 822/1841

example

Six liters of fonerde- (corundum) grains (4 - 6 mm in diameter) are soaked for half an hour in a 1 $ strength by weight potassium hydroxide solution "The grains are taken out from the solution and dried no longer than 200 ⁰ O at. You will then half an hour with a melt of nickel "-Ur any ini were soaked _t PeilUranyInitrat was prepared by melting together 5 parts Niokelnitrat with an '!. The granules are removed from the melt and allowed to proceed for 45 minutes before being caleiniert four hours in a stream of air at 400 ⁰ C. The nickel-uranyl cycle was then repeated until the required nickel concentration was reached. The final composition of the catalyst was $ 17 nickel, $ 13.7 urane, and $ 0.11 potassium. The catalyst was first put into operation in a stainless steel reaction tube as follows «

The reactants of light straight run gasoline (virgin naphtha? Endsiedepunkts 185 °), water vapor and lean gas were the reaction vessel (0.2 cubic feet) at an inlet temperature of 52Ö ⁰ G and at speeds of 3 g gasoline per hour, 19.5 kg (43 lbs. ) Water vapor per hour and 8.5 m (300 cubic feet) lean gas per hour supplied, with the reaction under a pressure of about 15 atti (220 psig »)

Equilibrium value of took place. There were / about 600 c »v. manufactured »The system

109822/1841

ran 600 hours under these conditions. Then the reaction rate was changed to generate town gas. The new amounts were 2.23 grams of gasoline per hour, about 20 kg (44 lbs.) Of water vapor per hour, about 9.9 w * (350 cubic feet) of lean gas per hour at about 13.5 atmospheres (200 psig). Equilibrium gases of approximately 500 cv were generated. It was driven a further 600 hours under these conditions.

The activity of the catalyst was at the end of the above Working hours practically unchanged. Next was a deposition of carbon on the catalyst is negligible.

An examination of the reforming sys- tem revealed no trace. Corrosion of the kind that normally occurs when using catalysts containing more than $ 0.5 of alkali.

The invention also includes a catalyst composition made by the process of the invention. The nickel content of the catalyst composition is preferably between 2 and 80 % and the uranium content between 5 and 30%, both expressed as the weight of the metal, based on the total weight of the catalyst composition.

The invention also comprises a process for reforming hydrocarbons with steam, as carried out in the presence of a catalyst prepared by the process according to the invention .

1 0 9 8 2 2/18 A 1- Check patient -

Claims (6)

Claims 5 1. Process for the production of a catalyst mass for the reforming of hydrocarbons with steam, the contains the following components «(1) nickel oxide and / or a Pre-stage for this, possibly together with elemental nickel? (2) Uranoso-uranium dioxide and / or uranium trioxide and / or a precursor for uranoso-uranium dioxide and / or uranium trioxideί (3) a catalyst carrier containing aluminum oxide and / or an alkaline earth oxide? (4) an alkali metal compound other than one halogen-containing, whereby the alkali compounds or their as defined precursor and the uranium and nickel compounds are deposited on the carrier, characterized in that, that the alkali compound before the addition of the uranium and nickel compounds deposited to the carrier on the catalyst carrier is, and that the amount of alkali compound in the catalyst mass to less than 0.5 #, expressed as the weight of the Alkali metal, based on the weight of the total catalyst mass, is measured. 2. The method according to claim 1, characterized in that the addition of the alkali compound is effected by the catalyst support with an aqueous solution of the alkali compound or its preliminary stage defined above, whereupon the treated catalyst is washed if desired or necessary. 109822/1841 3 * Method according to claim 2 _f, characterized in that the washing is effected ,,, by the catalyst support with a solution 'vqib. one or more other components of the catalyst mass treated * 4. The method according to claim I. to 3, characterized in that that the alkali compound to amounts of 0.05 to 0.3 #, expressed as the weight of the alkali metal, based on the weight of the total catalyst mass, 5 »Method according to claim 1 to 4, characterized in that that the alkali compound to amounts of 0.1 to 0.2 f &, expressed as the weight of the alkali metals, based on the weight of the total catalyst mass, is measured. 6. Use of a catalyst composition, prepared according to the Process according to Claims 1 to 5 for the formation of Hydrocarbon. 109822/1841