A kind of porous silicon oxide and its synthesis process

Abstract

The invention provides porous silica and a synthesis process thereof. According to the porous silica, the composition is amorphous silica, the size of particles is 7-15 microns, the particles consist of 20-60nm silica primary particles, the specific surface area is 50-180m<2> / g, the porous silica has the characteristic of graded pore distribution and has the pore size of 5-40nm, and pores with the pore size of 9-12nm and pores with the pore size of 40-50nm are of centralized distribution. The synthesis process of the porous silica comprises the following steps: (1) firstly, uniformly mixing silica sol and distilled water, then, adding white carbon black, and stirring under ultrasonic conditions, so as to obtain a mixture; (2) adding an inorganic base into the mixture obtained in the step (1) under the condition of stirring until the inorganic base is completely dissolved, and then, drying the mixture; (3) roasting the mixture obtained in the step (2), washing and drying, thereby obtaining the porous silica. According to the process provided by the invention, expensive organic template agents are not used, operating steps are simple and feasible, and the production cost is low.

Description

technical field [0001] The invention belongs to the field of synthesis of porous inorganic materials, in particular to a porous silicon dioxide material and a preparation method thereof. Background technique [0002] Porous silica materials have broad application prospects in the fields of catalysis, adsorption, separation, biomaterials, energy and the environment. At present, the technology for the preparation of porous silica materials is very mature, and is still developing. For example, mesoporous silica, also known as mesoporous molecular sieve materials, is a research hotspot, and there are many types prepared, such as M41S series, SBA15 etc. The synthesis of mesoporous molecular sieves requires several substances such as surfactant, water, silicon source, acid or alkali, among which surfactant as template is the most critical factor. Due to the in-depth research, many theories have also been proposed, such as the liquid crystal template mechanism, the rod self-assem...

AI Technical Summary

Problems solved by technology

This method is similar to the process of zeolite acid-base post-treatment to create secondary pores. Since the pores are formed by acid-base corrosion of silica gel, the loss of silicon will inevitably occur, and the higher the porosity, the greater the loss of silicon, which not only causes waste of raw materials, also cause serious pollution

[0008] At present, most of the existing preparation methods of porous silica materials use expensive organic substances as templates or organic additives, and the operation steps are relatively step-by-step. chamber to industrial production

And the existing technology still needs to be improved in the preparation of special materials, such as the control of particle size and shape, the control method of pore size distribution and pore size, there is still a huge room for improvement

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