DE814138C - Process for carrying out catalytic reactions - Google Patents

Description

Process' for carrying out catalytic reactions It is known that one catalytic reactions, especially to improve hydrocarbon oils, in the presence of alumina, which is provided with catalytically active metal compounds is able to perform with success.

It has now been found that it is particularly advantageous to use a dead earth as a catalyst for the purposes mentioned, which is produced by precipitating alumina hydrate from an aluminum salt solution at temperatures above 80 'and a pil value between about 7 and 10 and subsequent heating and which is provided with metal compounds of metals of the 5th and 6th group of the periodic table, expediently together with those of the metals of the iron group. The alumina carriers produced in the aforementioned way have a high absorption capacity, a low bulk density and, in connection with the heavy metal compounds mentioned, a particularly high catalytic effectiveness. The oxides or sulfides of the metals of the 5th and 6th groups and of the iron group are preferably used. The catalysts are particularly effective in hydrogenation , at normal or elevated pressures and in refined pressure hydrogenation. Also for other catalytic reactions, e.g. B. fat hardening, production of olefins and aromatic hydrocarbons, the catalyst can be used.

For the hydrogenation of monounsaturated and polyunsaturated hydrocarbons and the refining or pretreatment of hydrocarbon oils or their fractions as well as waxes or fats, the undesirable oxygen, sulfur, nitrogen compounds and / or contain components that are easily polymerizable when heated, this has been proven Clay in compounds with oxides or sulfides of molybdenum or Tungsten on the one hand and nickel or cobalt on the other hand have proven to be particularly advantageous.

To produce the clay, the aluminum salt solution and the precipitant are poured into a suitably heated vessel or a suitably heated liquid without preheating. It is necessary here that temperatures above 8o ', z. From 85 to 100 ', and a pH between about 7 and 10 can be maintained. One can apply also temperatures above the boiling point of the reaction mixture at atm mosphärendruck by at in a closed vessel, for example under pressures of 5 and more, operates.

The precipitate is expediently still hot liquid, generally in any case at temperatures not below about 4 ° to 5o ', separated and then washed out. In contrast to the usual way at lower temperatures precipitated alumina hydrate precipitates, the precipitate can easily be in proportion Wash salt-free with hot water for a short time.

The alumina hydrate produced in this way can, after drying, preferably at i oo to i 50 ', be processed without difficulty in a press onto shaped articles which differ from alumina hydrate shaped articles produced in other ways by their particularly high hardness. By heating to above 300 ', in particular 300 to 600', solidly formed active alumina is obtained.

After soaking with solutions of compounds of the metals mentioned is again heated to above 3oo '. Is heating in the presence of hydrogen sulfide carried out, the corresponding sulfides are obtained.

The catalysts obtained in this way are particularly effective when they contain about 5 to 45 parts, expediently 10 to 30 parts, of an oxide or sulphide per 100 parts of alumina. of tungsten, molybdenum, chromium or vanadium and 0.5 to 10 parts, in particular 1 to 6 parts, of an oxide or sulfide of a metal of the iron group, in particular of nickel or cobalt.

In the pretreating or refining pressure hydrogenation of hydrocarbon oils, for which these catalysts are particularly suitable, a temperature of 380 to 460 'and throughputs of 0.5 to 2.5 kg of starting material per liter of catalyst space and hour are selected and the reaction is carried out in such a way that only a few low-boiling products are formed. The products obtained in this way have a good degree of purity. on and are for a subsequent catalytic, z. B. splitting further processing well suited.

Example An aluminum nitrate solution, the concentration of which corresponds to an Al 203 content of 8%, and a z5% ammonia solution are poured simultaneously into a vessel heated to 95 ' so that the mixture of the solutions in the vessel has a pH value of 7 . The still hot solution, together with the precipitate formed, is placed on a filter press and the filter cake is washed with water of 7o to 4 hours for 3 to 4 hours. The alumina hydrate obtained in this way, after drying, is crushed, pressed into pills and then heated to 300-350 '. The mass has a bulk density of 0.35 to 0.4o kg / l.

The formed clay is treated with an ammoniacal solution of tungstic acid and nickel sulfate soaked, dried at 140 'and in a stream of hydrogen sulfide 40o to 4500 sulphurised. The pills are then ground, re-pressed and inserted sulphurized the second time. The finished catalyst contains 70% alumina, 27 "/ o tungsten sulfide and 30/9 nickel sulfide.

A bituminous coal medium oil with i8% is passed over this catalyst Phenols, 2% organic nitrogen compounds and a little sulfur compounds together with hydrogen under a pressure of 25o at at 420 'and receives a refined Medium oil which can be further processed catalytically without problems, e.g. B. can split.

Claims (1)

PATENT CLAIM: Process for carrying out catalytic reactions, in particular for improving hydrocarbon oils, characterized in that an alumina is used as the catalyst; which is produced by precipitating alumina hydrate from an aluminum salt solution at temperatures above 8o ', a pH value between about 7 and 10 and subsequent heating, and that with metal compounds' of metals of the 5th and 6th groups of the Periodic Table, suitably together with those of the metals of Iron group, is provided.