Preparation method of high activity oxidized nanocrystalline cellulose based titanium dioxide

Abstract

The invention discloses a preparation method of nano titanium dioxide with a high catalytic activity. The preparation method comprises the following steps: preparing raw materials: a butyl titanate precursor and diformyl nanocrystalline cellulose, which is obtained through an oxidization treatment; optionally adding a thickening agent and a surfactant, preparing a butyl titanate solution and a diformyl nanocrystalline cellulose solution, mixing two solutions under high speed sheering to obtain a uniform mixture, and subjecting the mixture to a gelation and high temperature calcination treatment to obtain the target product. According to the preparation method, oxidized nanocrystalline cellulose rich in diformyl groups is taken as the basic material, and under the effects of auxiliary materials such as thickening agent, surfactant, and the like, during the process of hydrothermal-freeze drying and gradient-heating calcination, the n-butyl titanate precursor is induced to carry out crystallization so as to form wheat-ear-shaped nano titanium dioxide crystal particles. The crystal particles can be well dispersed in water, thus the efficiency on processing the pigments in wastewater is effectively improved, and the provided titanium dioxide can degrade more than 98.5% of methyl orange within 12 minutes, in the best case.

Description

technical field [0001] The invention relates to a preparation method of nanometer titanium dioxide, in particular to a preparation method of highly active oxidized nanocrystalline cellulose-based titanium dioxide, and belongs to the technical field of preparation of inorganic non-metallic nanomaterials. Background technique [0002] In recent years, as the world's environmental problems have become increasingly serious, photocatalysis has become an important means of degrading environmental pollutants. Titanium dioxide has been widely used in the field of photocatalysis due to its advantages of low price, non-toxicity and good stability. In the early studies, most of the suspension systems were composed of titanium dioxide powder and wastewater, but the suspension system often had disadvantages such as easy agglomeration of solid particles and poor catalyst efficiency. The catalyst has a low probability of collision with the target molecule. Therefore, how to prepare a tit...

AI Technical Summary

Problems solved by technology

[0010] In the above invention patents 1-4, there is no mention of the use of nanoscale cellulose in the preparation of titanium dioxide composites, while invention patents 5-6 use nanofibers or nanocrystalline cellulose, but invention patent 5 does not It does not involve the preparation of nano-titanium dioxide particles with special forms, and the invention patent 6 does not use high-temperature calcination steps, and its prepared products are square or needle-shaped

In addition, none of the invention patents 5-6 mentioned the degree of improvement in the catalytic activity of the prepared nano-titanium dioxide products

[0011] In addition, the preparation results around nano-TiO2 crystals in the prior art show that the dispersion of ordinary granular TiO2 in the application system is poor, and it cannot be fully contacted with the target to achieve a sufficient reaction, which is also to a large extent limits the scope of application of its finished product

Images