CS257459B1 - Involvement of cobalt recovery from the cyclohexene oxidation process - Google Patents

Abstract

The connection for recovering cobalt from the reaction mixture consists in that it contains extractors of the reaction mixture and the hydrolyzed reaction mixture, the outputs of which are connected to a mixer further connected to a magnetic water conditioner and an ion exchange filter.

Description

The invention relates to a circuit for the poor recovery of cobalt from the process of oxidation of cyclohexane to cyclohexanone and cyclohexanol.

The oxidation of cyclohexane to cyclohexanone and cyclohexanol by air takes place in the presence

24Co ions as catalyst. After the oxidation of cyclohexane, cobalt is not recovered and, through the by-products of the reaction, it reaches the incineration plant in the ashes for the ash-flue-gas sludge. The by-product of cyclohexanone production is soda, which contains cobalt. This negatively affects its quality and thus the possibility of use. This leads to irreversible losses of cobalt and the environment is polluted with valuable raw material.

The principle of the invention for the recovery of cobalt from the cyclohexane oxidation process according to the invention is that it consists of a reaction mixture extractor and a hydrolyzed extraction mixture extractor whose aqueous phase outlets are connected in a mixer whose outlet is connected to a magnetic water treatment inlet. is connected to an ion exchange filter inlet. A pressure air supply is also connected to the ion exchange filter.

The present invention makes it possible to recover cobalt from the cyclohexane oxidation process in the form of regeneration solutions from ion exchange filters.

Using the circuitry of the present invention, it is possible to obtain up to 95% of the cobalt fed to the homogeneous cyclohexane oxidation reactor. The advantage of the circuitry according to the invention is that it uses positional energy for its function. The attached figure is a schematic circuit diagram for the recovery of cobalt from the cyclohexane oxidation process, where the reaction mixture extractor JL operates at 60-90 ° C and the hydrolyzed reaction mixture extractor 2 at 80-120 ° C. The extraction agent is water in both cases. As the extractor 2 of the hydrolyzed reaction mixture, an aqueous organic phase separator from the separation of distillation residues after acid hydrolysis can be used, at the same time the extraction of cobalt from the organic residues into the aqueous phase takes place. In Extraction 2 for + 2, the second stage of extraction of Co ions takes place with water.

As an extractor 2 of the hydrolyzed reaction mixture, an exj continuous rotary centrifuge for liquid phases can be used. The extraction agent is the aqueous phase of the centrifuge.

The mixing of the extracting agents from extracts 1 and 2 takes place in the mixer 3, which in the simplest case can also be an expanded pipe. The ion exchange filter 5 consists of one and most preferably three columns packed with a strongly acidic cation exchanger, where the cobalt is captured in the form of Co ions. From this it is obtained in a known manner as ion exchanger regenerate 7.

The wiring can also be applied separately with the individual extractors. When applying only the extractor! about 50 to 60% of the cobalt fed to the oxidation is obtained. In the connection according to FIG. even with a second extraction stage in the hydrolyzed blend extractor 2, the cobalt extraction rate increases to 90-95% of the amount fed to the oxidation.

Example 1

Extraction water obtained from the extraction of the reaction mixture containing cobalt at a concentration of 70 mg / l (300 m extr of extraction mixture is extracted with ^7H 2 ^{O, temperature} 78 ° C) is passed through a magnetic water purifier and from there to an ion exchange tower filled with saliva. cation exchange. The cation exchange resin is saturated with cobalt and, after regeneration, the regenerate also contains Co at a concentration of 30 g / l. A total of 55% of the cobalt introduced into the reaction mixture is obtained. Cobalt in extraction waters has not been proven.

Example 2 of the extraction water from the extraction of the reaction mixture containing Co 80 mg / l was combined with

A m of extraction water from the extraction of the hydrolyzed reaction mixture with a cobalt content of 60 mg / l. 95% of the cobalt fed to the reaction mixture was obtained.

Claims (4)

Extraction water from the extraction of the hydrolyzed reaction mixture with a cobalt content of 60 mg / l was obtained. 95% of the cobalt dispensed into the reaction mixture was obtained. SUBJECT OF THE INVENTION 1. Involvement of cobalt recovery from cyclohexane to cyclohexanone acyclohexanol oxidation, characterized in that it consists of an extractor (1) of the reaction mixture and an extractor (2) of the hydrolyzed reaction mixture, the outlets of which are connected through the mixer (3) to the input of the magnetic water treatment (4), the outlet of which is connected to an inlet to an ion exchange filter (5), to which a pressurized air supply is also connected. 2. Connection according to claim 1, characterized in that a phase separator after acid hydrolysis of the distillation residues is used as the extractor (2) of the hydrolyzed mixture. 3. Connection according to claim 1, characterized in that a rotary continuous centrifuge is used as the extractor (2) of the hydrolyzed reaction mixture. 4. Connections according to claim 1, characterized in that the ion exchange filter comprises three parallel-connected columns filled with a strongly acidic cation exchanger. 1 drawing