Abstract: A method for producing a water absorbent resin, the method including a polymerization step, a drying step, a classification step, and a surface crosslinking step. The classification step carried out before or after the surface crosslinking step requires use of a tapping material and a metal sieve mesh, in which the tapping material being heated at 40° C. to 100° C. is installed below the metal sieve mesh, and the metal sieve mesh has an area of 1 to 10 m2/sheet. The classification step further requires introducing a classification aid particle, which has a specific gravity different from that of the water absorbent resin, to the metal sieve mesh; and monitoring the presence or absence of damage to the metal sieve mesh.

Abstract: In manufacturing ethylene oxide by catalytic vapor phase oxidation of ethylene, a process comprising adding, as liquid, an organic halide as a reaction inhibitor into the ethylene raw material gas flow is provided. According to this process, ethylene oxide can be manufactured stably and in high selectivity.