DE807814C - Process for the production of nickel and nickel mixed catalysts, in particular for the hydrogenation of organic compounds - Google Patents

Description

Process for the production of nickel and nickel mixed catalysts, in particular for the hydrogenation of organic compounds It is known that in Bred suitable form nickel is catalytically effective, in particular the addition from hydrogen to organic compounds, called hydrogenation, catalytically accelerated or even made possible in the first place. Technology makes of this important insight widely used, such as 13. in the hydrogenation of naphthalene to tetrahydro- and decahydronaplitlialin or from phenol, etc. A very large field of application The catalytic hydrogenation also represents fat hardening, d. H. the conversion of liquid, unsaturated fatty oils into more or less extensive saturated fats, no longer liquid at ordinary temperature. si »d. nickel can generally only have a catalytic effect if it is in finely divided form is used from a large surface. Such is used in technology in essentially achieved by two primarily used processes. After the older one Processes are basic nickel carbonate or oxide hydrate on a carrier substance, like kieselguhr or the like from nickel solutions, e.g. B. by alkalis, such as soda or alkali lye, dejected. The precipitate is filtered off, washed out and dried. The same must then at a relatively high temperature of about 400 ° by hydrogen are reduced and thus maintains the catalytically active activity.

In newer processes, nickel formate becomes in the way active nickel is produced that this compound in vacuum preferably in Mixture with the oil to be hydrogenated, decomposed at temperatures between Zoo and 25o ° and then stabilized by hydrogen. This way of working is technical easier to carry out than the aforementioned older method and therefore has this largely displaced.

Further proposals for the preparation of high activity catalysts use the results of modern research directions. So z. B. So-called. Raney nickel produced by being made of suitable powdered nickel-aluminum alloys Alkali leaches the aluminum is dissolved out, or metallic nickel, z. Am In the form of chips, it is alternately oxidized and reduced several times.

The aim of all procedures is to use suitable working methods to Fine distribution of the nickel with a large surface area necessary for catalytic effectiveness of a certain structure.

It has now been found that it is technically particularly advantageous Way highly effective unsupported and easily reducible nickel catalysts, in particular for the hydrogenation of organic compounds, obtained when crystallized nickel double salts or nickel complex salts with a dissolved precipitant in a topochemical way, d. H. by localized reaction, expediently under mechanical, the course of the Reaction of accelerating working through converted to insoluble nickel compounds will. This reaction is advantageously carried out so that the starting nickel salts through Soda solution or ammonium carbonate solution or with soda solution and carbon dioxide or Ammonium carbonate and carbon dioxide converted into basic or neutral nickel carbonate will.

Such topochemical reactions (conversion of a crystallized, soluble compound in the solution of a suitable precipitant) are on others Areas already known. It was z. B. an active alumina hydrate shown by certain properties (Alukol). But one could from this fact not readily deduce that by topochemical conversion of soluble nickel salts an active nickel catalyst would be formed in addition to basic or neutral carbonate. In fact, experiments have shown that z. B. topochemically from nickel sulfate crystals Basic or neutral nickel carbonate represented, regardless of whether it is soda or Ammonium carbonate solution alone or in conjunction with carbon dioxide as a precipitant was in no way considered a particularly effective hydrogenation catalyst represents useful nickel compound. In contrast, there are soluble double salts such as nickel ammonium sulfate Ni S 04 (N H4) 2 S 04 -6H20, nickel potassium sulfate Ni S 04.

'K2 S 04 - 6 H2 O or nickel sodium sulfate Ni S 04. Nag S 04 # 4 H2 O and the like. Suitable starting materials which, in a topochemical manner, in neutral or converted basic carbonates, easily reducible, particularly effective catalysts result.

In the topochemical representation, the reaction is carried out appropriately at room temperature, i.e. at 15 to 30 °; by choosing the degree of division the timing of the reaction can be influenced within certain limits. If you turn so z. B. the crystals in fine to gritty distribution, then the reaction has already ended after stirring for 2 to 3 hours. Using a practically quantitative yield can be obtained from alkali double salts, in particular when soda solution is used as the precipitant. at the use of nickel ammonium sulphate as a starting material or when with ammonium carbonate is precipitated, the yield of carbonate is naturally due to the presence of Ammonium ions not entirely quantitative. However, the nickel that has gone into solution can from the filtrate of the precipitation by appropriate evaporation and cooling easily as Nickel ammonium sulfate can be recovered.

As starting materials for the topochemical representation of effective nickel catalysts Instead of double sulfates, other double salts or complex salts can also be used be e.g. B. N ickelammoniumnitrate or N ickelammoniakkomplexsalze etc. These are generally not as easily accessible as nickel ammonium sulfate or nickel potassium sulfate.

The catalytic properties of the represented by topochemical reaction Catalysts are not just completely the contacts previously used in technology equal, but in certain cases even superior, e.g. B. called hydrogenation aromatic hydrocarbons. They jump on easily, d. H. they direct the transfer of hydrogen immediately one. Their handling is similar to that of nickel formate, with the advantage that there is no decomposition in a vacuum; they are mixed with the material to be hydrogenated and treated with hydrogen at temperatures around 24o °, this initially being primarily the nickel-containing compound is reduced, which then reduces the organic matter causes. After the hydrogenation product has been separated from the nickel catalyst, this is as usual, capable of further hydrogenation reactions.

The application of the topochemical reaction for the purposes of the invention is not restricted to the production of catalysts with a simple composition; it can also be used in an equally advantageous manner for the production of mixed catalysts. It is known that catalysts of this type which contain two or more metal compounds are often more effective than catalysts of simple composition or are capable of influencing the catalytic reaction in a certain direction. So have z. B. Nickel contacts that contain copper have a higher catalytic effectiveness than simple nickel contacts. Accordingly, you can use the inventive method for the preparation of mixed nickel catalysts z. B. perform in such a way that the nickel double salts or nickel complex salts of the implementation in the mixed with other crystallized metal double salts or metal complex salts will. Furthermore, for the same purpose in certain modification of the above-mentioned working also wise mixed crystals of nickel double salts or nickel conilex salts with other metal double salts or Met111 complex salts or? Ui- Schungen of various such mixed crystals of the Implementation are subject to. The starting material for this training Guide to the method according to the invention for the topochemical production of such 'mixed catalysts appropriate z. 13. crystallized Nickel potassium and copper potassium sulfate serve that after mixing with each other the togochemical Be subjected to dissolution or as mixed Crystalline nickel-copper-potassium sulphate deposited get implemented. It was found that that this mixed catalyst is particularly high is effective when the ratio of nickel to copper .1 to 8 parts of nickel to i part of copper. Here- is achieved by (let the catalytic transfer generation of hydrogen particularly easily goes. Thus, fatty oils are easily ratur uni i _3o- hydrogenated without pressure, while the so far Iwkaruiten catalysts temperatures around i 8o be applied. The technical advantages of togochemical manufacture position of simple and compound Nickel and nickel catalysts are available mainly based on the fact that it is easily accessible I) ol>1> cl salts are used that the reaction at room temperature in an easy-to-create Apparatus can be carried out and that the h @ älll »products easily by simply washing them out finite water from the soluble reaction products can be freed. For the catalytic effect sainkeit of the togochemical reaction produced by the method according to the invention neutral or basic carbonates can be use of suitable double salts or mixed Crystals not only have a particularly desirable fine Distribution of the catalyst metals can be achieved, but it also becomes a certain surface and crystal structure thing, which is also beneficial. EXAMPLE 1 100 g of fine to granular nickel ammonium sulfate are gradually introduced into a solution of 480 g of sodium carbonate in water at about 20 ° with thorough stirring. After the nickel ammonium sulfate has been introduced, the mixture is stirred for a further 2 to 3 hours. A moderate green precipitate of basic nickel carbonate is formed which, after the reaction has ended, is suctioned off through a suction filter and washed free of sulfate about 6 to 8 times with about 1/2 a liter of warm water each time. After drying at 80 to too °, 28o g of light green togochemical basic nickel carbonate with a nickel content of 47% (yield about 87%) are obtained. The basic nickel carbonate obtained in this way is a highly active catalyst for the hydrogenation of aromatic organic compounds for fat hardening, etc.

Example2 217 g of fine to granular nickel sodium sulfate are dissolved in a solution of 10 g of sodium carbonate in 2 liters of water at about 20 to 25 ° with thorough stirring, and then stirred for a further 2 hours after the addition. Light green basic nickel carbonate is formed, which is filtered off with suction, washed and dried as in Example i. Yield 66 g with so to 5 1% nickel (98 to roo% of theory). Beispie13 125 g of fine to granular nickel sodium sulfate are, as described in Examples 1 and 2, reacted with a solution of 168 g of sodium hydrogen carbonate (sodium bicarbonate) in water and treated further in the same way as described in Examples 1 and 2. Yield 35 g of neutral nickel carbonate with 44 to 45% nickel (97 to 100% of theory). The product thus obtained, like those described in Examples i and 2, is a very easily reducible, very active catalyst for many types of hydrogenation of organic compounds. For example, 218 g of fine, granular potassium nickel sulfate are converted into a solution of tob g of soda in 2 liters of water, as described in Examples 1 to 3, and treated further in the same way as described in Examples 1 to 3. Yield 56 g of basic nickel carbonate finite 49 to 50% nickel (98 to 100% of theory). EXAMPLE A mixture of 218 g of potassium nickel sulfate and 30 g of potassium copper sulfate are added to a solution of 75 g of soda in 1.25 l of water, as described in Examples i to 4, and, as described above, converted to basic nickel-copper carbonate . There are 62 g of basic carbonate with 40% Ni and 6.2% Cu, which after reduction with hydrogen at 210 ° a highly active catalyst z. B. represents for fat hardening. Example 6. 225 g of copper-nickel-potassium sulfate with 10.34% Ni and 1.55% Cu are, as described above, added to a solution of 75 g of soda in 1.25 liters of water and, as in Examples i to 5 described, treated further. 63 g of basic copper-nickel carbonate are formed.

Claims (2)

PATENT CLAIMS: t. Process for the production of nickel and nickel mixed catalysts, in particular for the hydrogenation of organic compounds, characterized in that crystallized nickel double salts or nickel complex salts with a dissolved precipitant in a topochemical manner, i.e. 1i. can be converted into insoluble nickel compounds by means of a localized reaction, z-, n-corner with mechanical working through. 2. Production of catalysts according to claim t, characterized in that the nickel double salts or nickel complex salts of the reaction in a mixture with other crystalline sated lfetall <l <lllielsalzen lizw. Metal complex salt. 3. Process for the production of catalysis goals according to claim i wild 2. draws, lall \ lischl_A-istall of nickel double salt lizw. Nickel complex salts with others Nletall double salts lizw. Metal complex salts or parts of various such mixed Crystals are subjected to disintegration.