A kind of preparation method of nano silicon dioxide

Abstract

The invention discloses a preparation method of nano silicon dioxide. On the basis of the existing sol-gel technology, after dissolving ethyl silicate in organic solvent and water, the sol is prepared by controlling the pH, temperature and stirring speed of the solution, when the sol particle range is within 1-10nm Finally, the stencils with hydroxyl groups are vertically put into the solution at a certain interval, and then taken out and washed with water at the same time after a certain interval to obtain nano-silica. The preparation method obtains less impurity content in the nano silicon dioxide, avoids the use of a dispersant, and uses less organic solvent in the preparation process, and the preparation method is simple to operate and greatly shortens the coagulation time.

Description

technical field [0001] The preparation of nano silicon dioxide belongs to the preparation technology of inorganic nano materials, and specifically relates to a method for preparing nano silicon dioxide on the basis of sol-gel technology with ethyl silicate as a silicon source. Background technique [0002] Nano silica is amorphous white powder, which is a non-toxic, odorless and non-polluting non-metallic functional material. Nano silica has small size effect, surface interface effect, quantum size effect and macro quantum tunnel effect and special Optical and electrical properties, high magnetoresistance, non-linear resistance, and high strength, high toughness, and good stability at high temperatures, nano-silica can be widely used as catalyst carriers, separators, and adsorbents and chemical biosensing materials. [0003] At present, there are many patents for preparing nano-silica on the basis of sol-gel technology, such as CN101891209A, which uses citric acid, tetraeth...

AI Technical Summary

Problems solved by technology

[0004] In the current patents on the use of sol-gel technology to prepare nano-silica, in order to prevent the agglomeration of the prepared silica, it is necessary to add a dispersant to obtain the required nano-silica, which will inevitably cause problems in the prepared silica. Silica is mixed with certain impurities, and in order to dissolve these dispersants, the amount of organic solvent will increase relatively