Process for producing microcrystalline alpha-alumina by microwave calcination

A process for producing microcrystalline alpha-alumina by microwave calcination, wherein, comprising the following steps:

• S1. adding a composite mineralizer to an alumina rave material and nixing uniformly, to obtain a mixture;
• S2. putting the mixture obtained in the step S1 into a ball mill for ball milling, to obtain a milled alumina powder;
• S3. adding a certain proportion of a microwave absorbent into the milled alumina powder obtained in the step S2 and stirring evenly, and then extruding by a press, to obtain an alumina green body;
• S4. drying the alumina green body obtained in the step S3, to adjust a moisture content of the alumina green body;
• S5. feeding the alumina green body dried in the step S4 into a microwave kiln, then heating the microwave kiln to a set temperature, and calcining for a certain period of time, to obtain an alpha-alumina clinker;
• and
• S6. pulverizing the alpha-alumina clinker obtained in the step S5, to obtain the microcrystalline alpha-alumina.