A kind of preparation method and application of dialdehyde base cellulose salenmx catalyst

Abstract

The invention discloses a preparation method of a dialdehyde cellulose Salen MX catalyst. The method includes the steps of: 1) substituting the hydroxyl groups of 2nd and 3rd positions of cellulose into aldehyde groups, and adding ortho-aminophenol to perform a reaction at 50-70 DEG C for 2-4 h, filtering the reaction product to obtain a brown precipitate; 2) repeatedly washing the brown precipitate with ethanol, and drying the brown precipitate at room temperature to obtain a dialdehyde cellulose Salen MX ligand; 3) adding a transition metal compound and the dialdehyde cellulose Salen MX ligand to ethanol at the same time, performing a stirring reaction for 12-18 h at 40-70 DEG C under protection by N2, adding anhydrous LiCl, feeding air, and performing stirring reaction for 24-36 h at 30-50 DEG C; 4) filtering the reaction product to obtain a dark-brown precipitate, repeatedly washing the dark-brown precipitate with ethanol and water, and drying the dark-brown precipitate at room temperature to obtain the dialdehyde cellulose Salen MX catalyst. The dialdehyde cellulose Salen MX catalyst has excellent application prospect in the fields of catalyzing epoxidation of natural monoterpenes and copolymerization of epoxy compounds, is simple in preparation method, can be repeatedly used for more than eight times, is prepared with regenerable supporter, is high in yield and selectivity, and has advantages in industrial production of olefin catalytic epoxidation.

Description

technical field [0001] The invention relates to a catalyst technology supported by a natural polymer polymer material, in particular to a preparation method and application of a dialdehyde-based cellulose SalenMX catalyst. Background technique [0002] SalenMX catalysts have become the most studied catalysts in recent years because of their high catalytic efficiency, narrow molecular weight distribution, and easy modification. SalenMX can be used for the epoxidation of olefins, the copolymerization of epoxy compounds, etc., but the SalenMX catalyst is often dissolved in the solvent during the reaction, which is difficult to recycle. The catalyst is directly deactivated under high temperature conditions and is easy to generate Defects such as oxygen-bridged dimer μ-oxo-Mn(Ⅵ). Therefore, researchers began to focus on loading SalenMX on various carriers to achieve heterogeneity. There are three types of supports for heterogeneous catalysts: inorganic supports, organic monomer...

AI Technical Summary

Problems solved by technology

Inorganic carriers often have disadvantages such as harsh preparation conditions, small loading capacity, and easy detachment of catalysts; the synthetic monomers used in organic monomer polymerization polymer carriers often have certain toxicity, and the biggest defect is that the monomers are not renewable, such as polyaniline- Salen[patent number: CN201410137775.3], polypyrrole-Salen, etc.

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