Aluminum-containing cocatalyst

Abstract

The invention discloses an aluminum-containing cocatalyst which is used as a cocatalyst in a copper-based catalyst system in synthesis reaction of organic silicon monomers, preferably synthesis reaction of dimethyldichlorosilance. The aluminum is uniformly distributed and combined in a carrier, so that the aluminum-containing cocatalyst has the advantages that uniform mixing of the aluminum and silicon in a fluidized bed is facilitated; oxidation films on the surfaces of silicon powder and contacts are removed and the reaction activities of the silicon powder and the contacts are improved; the unnecessary loss of the aluminum in industrial production is reduced. Compared with a method in the prior art for adding the aluminum into a fluidized bed reaction system by using particle metallic aluminum powder, the aluminum-containing cocatalyst also has the advantages that aluminum components are low in contents of harmful impurities and high in purity; the aluminum-assisted catalytic components can be uniformly added into a synthesis reaction system during synthesis of the organic silicon monomers; the utilization efficiency of the aluminum can be improved; the oxidization films on the surfaces of the silicon powder and the contacts can be well removed; the improvement of the activity of the synthesis reaction is facilitated; the space time yield of the fluidized bed is improved; the cost of the industrial production is reduced; the aluminum-containing cocatalyst has remarkable economical benefits.

Description

technical field [0001] The invention relates to the synthesis reaction of organosilicon monomers, in particular to the field of co-catalysts in copper-based catalytic systems in the synthesis reaction of dimethyldichlorosilane, and more specifically relates to an aluminum-containing co-catalyst. Background technique [0002] Dimethyldichlorosilane, also known as dimethyl or M2 in industry, is one of the most important organosilicon monomers, and its consumption accounts for more than 90% of the total amount of monomers. It is a downstream product for the preparation of organosilicon. Important raw materials such as silicone oil, silicone rubber, silicone resin and silane coupling agent. [0003] Dimethyldichlorosilane is chemically synthesized from metal silicon powder and methyl chloride in a fluidized bed at a temperature of about 300°C by adding a catalyst (including a main catalyst and a cocatalyst). The synthesis reaction belongs to gas-solid - Solid multi-phase contac...

AI Technical Summary

Problems solved by technology

Because the amount of aluminum added in the fluidized bed reaction system is not much, and because these aluminum, silicon powder and copper powder added to the industrialized fluidized bed are often difficult to achieve very uniform mixing, the cocatalyst aluminum component is difficult Give full play to the catalytic effect, so that the synthesis reaction in the fluidized bed cannot reach the best state, especially when the activity of silicon powder is not good, and Al needs to be added to improve the activity of the contact body. This situation is more common.

In addition, when the state of the industrial fluidized bed is unstable, some aluminum powder, especially the ultrafine particles in the aluminum powder, are easy to be carried out from the local channel flow or unevenly distributed in the bed, which will make the reaction unable to reach the optimum level. The effect is not good, and the role of aluminum as a cocatalyst cannot be fully exerted