Preparation method of rare earth halide

Abstract

The invention provides a preparation method of rare earth halide. The method comprises the following steps: heating LnX3.nNH4X powder in a rare earth oxide crucible to obtain rare earth halide LnX3, wherein the rare earth element in the LnX3.nNH4X powder is the same as the rare earth element in the rare earth oxide crucible, Ln is selected from La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Sc and Y, X is halogen, and n is more than 0 and less than or equal to 12. According to the preparation method provided by the invention, the high-purity, anhydrous and oxygen-free rare earth halide can be obtained; and the anhydrous high-purity rare earth halide obtained by the method can be used for growing high-purity blocky single crystals or fibrous single crystals with excellent scintillation performance.

Description

technical field [0001] The invention relates to the technical field of new inorganic materials, in particular to a preparation method of rare earth halides. Background technique [0002] Metal halides are very important chemical raw materials and are widely used in the fields of catalysis, luminescence, and functional materials. In particular, the anhydrous and oxygen-free high-purity rare earth halides in metal halides are important raw materials for the preparation of scintillation crystals, but due to their strong hygroscopicity and easy oxidation at high Water halides are both important and difficult. [0003] At present, the commonly used high-purity anhydrous halide preparation methods mainly include two routes: [0004] 1) Get LnX in solution 3 with NH 4 A mixture or complex of X, and then the solution is concentrated and dehydrated under certain conditions to obtain LnX 3 · nNH 4 X powder solid, then heated in a quartz crucible to remove excess NH 4 X to obtai...

AI Technical Summary

Problems solved by technology

[0007] 1) At the stage where the temperature is higher than 400°C, as the temperature reaches 400°C, NH 4 X gradually transforms into gaseous NH 3 And HX, where HX is a strongly acidic and corrosive gas, will react with the quartz crucible, and the degree of reaction will become more serious with the increase of temperature, thus introducing the Si element in the crucible into LnX 3 , causing LnX 3 pollution

[0008] 2) The most commonly used quartz (SiO 2 ) when the crucible reaches a temperature above 500°C, some of the hydroxyl groups are released and combine with LnX 3 react to generate LnOX, thus causing LnX 3 elevated oxygen levels