Method for preparing complex chemical compound

Abstract

The invention relates to a preparation method of a complex chemical compound, which is characterized in that: degradable dispersion medium is added into the conventional coprecipitated product system, the isolation effectiveness produced by the dehydration and the decarburization of the dispersion medium at a special situation is utilized to prevent the aggregation of grains, thus, the reaction activity of the prepared complex chemical compound can meet the requirements of preparing luminescent materials with high performance based on the special specific surface area, and the grain sizes, the particle size distribution, the morphology, the luminous performance, the coating performance, the anti-deterioration performance and other specifications of the prepared luminescent material can meet optimizations. The preparation method of the complex chemical compound has the advantages of fast and controllable preparation process, easy realization of scale production and favorable product homogeneity.

Description

technical field [0001] The invention relates to a preparation method of a composite compound, in particular to a preparation method of a composite compound with specific specific surface area and dispersion index which can be used as a light-emitting material precursor. Background technique [0002] The specific electronic structures of Eu, Tb, Dy, Gd, Ce, and Mn elements make it possible to obtain a variety of functional materials by adjusting the matrix material and synthesis conditions. Especially when used as luminescent material activator ions, the emission spectrum can cover a wide range from ultraviolet to near infrared. At the same time, because the corresponding luminescent material has the advantages of high luminous intensity and high color rendering, it has been used in lighting and display etc. The field has been widely used, and the corresponding TV and energy-saving lamps have become an indispensable part of people's daily life. [0003] With the continuous d...

AI Technical Summary

Problems solved by technology

In actual operation, these conditions are very harsh and difficult to control. Once any one of the conditions changes, the batch of products will be difficult to settle and cannot be filtered, often causing great loss and waste.

For oxalate, although the product is easy to filter, the particle size is relatively coarse, and the particle size of the prepared luminescent material is also relatively large.

[0009] 2) The solubility products of rare earth ions and other ions in the system are often quite different, and it is difficult to control the homogeneous product during precipitation

[0011] If there are non-rare earth metal ions in the system, this phenomenon is even more serious, and the performance of the heterogeneous precipitate is unstable in actual use, and it is difficult to obtain compounds with accurate stoichiometric ratios.

[0012] 3) There is a difference in the local concentration of the precipitant in the precipitation reaction, resulting in a large difference in the particle size of the precipitate

Therefore, the statistical results often show a wide particle size distribution, which means that the dispersion coefficient of this product is relatively large.

[0014] 4) The washing process of precipitation needs to consume a lot of water and cause pollution at the same time

The washing process of the filter cake consumes a lot of water, and the solution after washing is often discharged without treatment due to the low ion concentration or cost problems, which is easy to cause pollution

In fact, on the premise that no impurities are introduced into the reaction vessel, the amount of impurities introduced in the subsequent steps is very small. Although the washing process can eliminate the impact of impurity ions as much as possible, the waste of water resources and pollution caused by this process cannot be underestimated.

[0016] 5) The filter cake drying and roasting process is prone to agglomeration, resulting in the reduction of the specific surface of the product

[0017] In order to obtain a dry co-precipitate, the filter cake is often dried and other treatments at present. It was found that the product compaction phenomenon is serious, and the specific surface area of ​​the product is less than 0.3. When used to prepare luminescent materials, it is easy to have large particle size and wide distribution. The phenomenon

This phenomenon can seriously affect the particle morphology and size of the final product if the precipitation conditions are not well controlled