Preparation method of surface amino-modified mesoporous molecular sieve

Abstract

The invention relates to a preparation method of a surface amino-modified mesoporous molecular sieve, which comprises the following steps: by using diisocyanate molecules as a bridge, grafting the diisocyanate molecules through the reaction of Si-OH on the silicon dioxide molecular sieve surface and one uramido group in the diisocyanate diisocyanate, and grafting the amino group through the reaction of the other uramido group of the diisocyanate and one amino group in the ethylene diamine molecule, thereby finally obtaining the surface amino-modified mesoporous molecular sieve material. The preparation process can not damage the mesoporous orderliness of the molecular sieve, the pore sizes are uniformly distributed, and thus, the mesoporous molecular sieve can be used in the fields of catalysis, adsorption, separation and the like.

Description

technical field [0001] The invention relates to a method for preparing a surface amino-modified mesoporous molecular sieve, which belongs to the field of mesoporous materials. Background technique [0002] In 1992, the researchers of Mobile Company reported the M41S series mesoporous materials with high specific surface area and high order for the first time [Natrue, 1992, 359, 710]. Mesoporous molecular sieve materials with different pore structures and pore sizes, such as MCM-41, MCM-48, HMS, MSU-X, SBA-15, SBA-16, MAS-7 and other mesoporous molecular sieves with different surface texture properties . In recent years, the surface organic functional modification of mesoporous molecular sieves has become an important research direction, such as sulfhydryl, carboxyl, sulfonic acid, amino and organic hydrophobic modification. As an important organic functional group, the amino group is favored because the amino group is easy to be positively charged and is a basic group. It ...

AI Technical Summary

Problems solved by technology

The co-hydrolysis polycondensation method is to directly add amino-containing organosiloxanes to the system for preparing mesoporous molecular sieves, and obtain surface amino-modified mesoporous molecular sieves through co-hydrolysis polycondensation of silicon sources. However, the mesoporous molecular sieves obtained by this method The mesopore order of molecular sieves is not high, and the amount of functionalization is low

The post-grafting method is to modify the surface of mesoporous molecular sieves by reacting Si-OH on the surface of molecular sieves with amino-containing organosiloxanes, but this method first introduces -NH 2 Easily form hydrogen bonds with Si-OH, thereby preventing further amino modification of Si-OH