Preparation method for high purity magnesium oxide powder

Abstract

The present invention relates to a preparation method for high purity magnesium oxide powder, and belongs to the field of hydrometallurgy. The preparation method comprises the following steps: dissolving magnesium chloride by deionized water to prepare a magnesium chloride solution; according to the dissolution equilibrium principle, calculating precipitation starting pH values of various impurity ions, and determining the precipitation pH value ranges of the impurity ions of Fe, Al, and Si; adding an alkaline reagent, adjusting the pH value, neutralizing the precipitation, and filtering to remove the impurities such as Fe, Al, Si, and the like, wherein the filtrate is provided for a spare use; adding an alkaline reagent to the filtrate, neutralizing the precipitation of Mg, filtering andseparating to obtain the filter cake; placing the filter cake in an oven, holding a constant temperature of 120 DEG C, and carrying out drying to obtain Mg (OH) 2; carrying out calcination for 3 hours at the constant temperature of 920 DEG C, and carrying out crushing and screening to obtain the MgO powder. According to the present invention, the method of the present invention has characteristics of simpleness, easy batch production and low cost; the metal impurity ions in the prepared MgO powder meet the requirements of the PDP medium layer to the purity of the MgO material, and the high purity magnesium oxide powder of the present invention can be used for preparation of the MgO optical coating material.

Description

technical field

[0001] The invention relates to a preparation method of high-purity magnesium oxide powder. The method of the invention has low cost and belongs to the field of hydrometallurgy. The powder prepared by the invention can be used to prepare the MgO optical coating material used for the medium layer thin film of PDP (plasma display screen). Background technique

[0002] At present, there are many preparation methods for MgO, and there are related preparation studies on high-purity MgO, but there is no report on the separation of specific impurity ions for PDP. At present, high-purity MgO is rarely obtained in China, and mass production has not been realized. For the preparation of MgO coating material for PDP abroad, relevant studies on purity control have been carried out, but MgCl 2 There is no public report for the relevant purification technology of the raw material. The sensitive impurities in the MgO material for PDP are mainly metal impurity ions Ca, Si...