A kind of cobalt catalyst and its preparation method and application

Abstract

The invention discloses a cobalt catalyst and a preparation method and application thereof. The preparation method of the cobalt catalyst disclosed in the present invention comprises the steps of reacting cobalt salt and optional auxiliary metal salt with polyvalent carboxylic acid in an alcohol solvent to obtain an organometallic cobalt complex, and then mixing the organometallic cobalt complex with a silicon-based sol- A gel precursor and a saturated monobasic acid having a carbon number of 2-4 are reacted to obtain a silica sol containing an organometallic cobalt complex, and then the silica sol containing the organic complex is subjected to steps such as liquid ammonia treatment. The catalyst provided by the invention is used for the catalytic hydrogenation of 3-cyano-3,5,5-trimethylcyclohexanone (IPN) to prepare 3-aminomethyl-3,5,5-trimethylcyclohexylamine ( IPDA), the highest conversion rate of IPN can reach 100%, and the highest selectivity to IPDA can reach more than 98%.

Description

technical field [0001] The invention belongs to the field of catalysts, and relates to a cobalt catalyst and a preparation method and application thereof, in particular to a framework cobalt catalyst and a preparation method and application thereof. Background technique [0002] 3-Aminomethyl-3,5,5-trimethylcyclohexylamine (isophorone diamine, IPDA for short) is a raw material for the preparation of isophorone diisocyanate (IPDI), polyamide, etc. Epoxy hardener. Isophorone diamine is usually composed of 3-cyano-3,5,5-trimethylcyclohexanone (isophorone nitrile, IPN for short), NH 3 and H 2 It is prepared by ammoniation and hydrogenation under the action of hydrogenation catalyst. Commonly used hydrogenation catalysts are framework Co (Raney Co) catalysts. [0003] Raney Co catalyst is a catalyst that has been commercialized. For example, the US Published Patent Document US6087296A discloses its preparation method as follows: using metal Co and Al as the alloy main body, ...

AI Technical Summary

Problems solved by technology

The disadvantage of the preparation method of this catalyst is: the yield of the target particles is not high (about 50%) during the crushing process of the alloy, and the others are all unusable alloy powders; meanwhile, the active layer of the catalyst is only about 5 μm, and most alloys Only as the substrate of the active layer, the metal utilization rate is extremely low, and the cost of the catalyst is very high; and a large amount of lye wastewater containing sodium metaaluminate will be generated during the activation process, and the treatment cost is high

The preparation process of the catalyst in this method is cumbersome and needs to be coated with a fluidized bed, and the strength of the activated hollow sphere particles is not high enough, which affects the later use

[0007] U.S. Patent US6337300B1 discloses that 15% polyoxymethylene copolymer is used as a binder, Co-Al alloy powder is molded, dried, baked at 800°C for 125min, and then activated with 20% NaOH solution at 80°C 120min prepares catalyst; This catalyst is used for IPN ammoniation hydrogenation and prepares IPDA, and IPN transformation rate is 99.9%, but IPDA selectivity only has 89.7%, makes hydrogenation product yield lower; In addition, catalyst particle crushing strength (Breaking Strength ) is only 120N / particle, and the utilization rate of cobalt in the catalyst is low, which increases the cost of the catalyst and is not conducive to the efficient utilization of resources; at the same time, a large amount of lye wastewater containing sodium hypochlorite will be generated during the activation process, and the treatment cost is high

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