Alpha-alumina carrier of silver catalyst for ethylene epoxidation as well as preparation method and application of alpha-alumina carrier

The invention relates to an alpha-alumina carrier of a silver catalyst for ethylene epoxidation as well as a preparation method of the alpha-alumina carrier. By adding a certain proportion of micron-scale alpha-alumina crystalline grains and silicon-containing aid compounds in a preparation process of the carrier, the prepared alpha-alumina carrier of the silver catalyst has relatively good porosity, specific surface area and pore structure, pores with the pore diameters of 0.5-1.5 microns are 40%-60% (volume) in pore distribution, and pores with the pore diameters of 5-10 microns are 10%-30% (volume) in pore distribution. The invention further relates the silver catalyst prepared from the alpha-alumina carrier and application of the silver catalyst in production of ethylene oxide through ethylene epoxidation. The silver catalyst prepared by dipping, drying and activating a constitution solution containing a silver compound, an organic amine compound, an alkali metal aid, an alkaline earth metal aid, a rheniu