The invention discloses a preparation method of high content insoluble
sulfur (IS). In the preparation technology, the procedures of extraction, washing, suction
filtration and
drying are continuously finished in the same drier, wherein the extraction is carried out under the protection of adding CS2 and N2; after extraction, mother solution is pumped off; CS2 is added twice for washing and then suction
filtration; then, jacket hot water is used for heating and
drying; the material is obtained after
water cooling; the extraction and
drying are carried out under rotation; suction
filtration and drying are carried out under the
vacuum pressure of 0.01 to 0.03MPa; a cavity of the drier is closed; and the drier only has one dynamic seal. By adopting the technological specification of the method, the materials is not transferred in the production without leakage; safety environmental requirements are satisfied; moreover, washing and suction filtration are carried out twice;
vacuum drying is carried out; each technological condition and technological parameter are selected reasonably and mutually matched; remaining insoluble
sulfur is reduced, thereby preventing IS from reducing into the insoluble
sulfur; accordingly, the content of IS is enhanced. Indicated by a test, in IS
powder prepared by the invention, the content of IS is not less than 98%.