A hydrogen sulfide purification method includes removing a lithium raw material by using a cyclone, from a mixed gas containing unreacted hydrogen sulfide and the lithium raw material which is generated in a process of producing lithium sulfide by a reaction of hydrogen sulfide and the lithium raw material.

Lithium sulfide is provided having, in an X-ray diffraction pattern as measured using an X-ray diffraction apparatus using CuK1 rays, a diffraction peak A at the position of 2=31.21.0 and a diffraction peak B at the position of 2=23.01.0, and a value of I.sub.b to I.sub.a of from 0.012 to 0.045, where the I.sub.a is an intensity of the diffraction peak A and the I.sub.b is an intensity of the diffraction peak B. Furthermore, a value of I.sub.c to the I.sub.a is preferably 0.024 or less, where the I.sub.c is an intensity of a diffraction peak C that is at the position of 2=21.31.2.

A method for preparing high-purity lithium sulfide by using industrial-grade butyllithium includes the following steps: step A: under an inert gas condition, thoroughly mixing 1.5-2.5 g of lithium chloride, 0.5 L of an industrial-grade n-butyllithium solution (2.5 mol/L) and 1.5-2.5 L of n-hexane to obtain a mixed solution, and charging the mixed solution into a sealed container; step B: under the sealed condition, firstly introducing H.sub.2S gas into a gas-washing bottle through a submerged pipe at a rate of 10.5 L/h, then introducing into the mixed solution through the submerged pipe, controlling the reaction temperature at 25-40 C., and continuously stirring for reaction for 4-6 h to obtain a reaction slurry; and step C: under an inert gas condition, filtering the reaction slurry with a G3 sand core funnel to obtain a crude lithium sulfide solid wet material.

A method for preparing high-purity lithium sulfide by using industrial-grade butyllithium includes the following steps: step A: under an inert gas condition, thoroughly mixing 1.5-2.5 g of lithium chloride, 0.5 L of an industrial-grade n-butyllithium solution (2.5 mol/L) and 1.5-2.5 L of n-hexane to obtain a mixed solution, and charging the mixed solution into a sealed container; step B: under the sealed condition, firstly introducing H.sub.2S gas into a gas-washing bottle through a submerged pipe at a rate of 10.5 L/h, then introducing into the mixed solution through the submerged pipe, controlling the reaction temperature at 25-40 C., and continuously stirring for reaction for 4-6 h to obtain a reaction slurry; and step C: under an inert gas condition, filtering the reaction slurry with a G3 sand core funnel to obtain a crude lithium sulfide solid wet material.