IRON SULFIDE AND PROCESS FOR PRODUCING THE SAME

摘要

The invention relates to an iron sulfide characterized in that it comprises from 85 to 100 wt% FeS2, from 5 to 0 wt% Fe1-X S (X:0 to 0.2), from 5 to 0 wt% Fe3O4 and from 10 to 0 wt% FeSO4 as determined by X-ray diffractometry, and that the secondary particles thereof each made up of primary particles having a particle diameter of from 10 to 400 nm have a 5O% volume-cumulative particle diameter of from 20 to 300 .mu.. The invention also relates to a process for producing an iron sulfide characterized by comprising the steps of introducing (a) an iron sulfate comprising, as a main component, ferrous sulfate monohydrate having a d50 of from 20 to 300 .mu. and (b) not less than stoichiometric amount of at least one sulfur compound selected from elemental sulfur in a powder, melt or vapor state and hydrogen sulfide into the fluidized bed of a fluidized burning furnace and then fluidizing, burning, and reacting the ingredients at a temperature of from 350 to 630.degree.C, excluding 630.degree.C, a superficial velocity of 0.1 m/sec or higher, and a pressure of 1 atm or higher using air as a fluidizing gas for utilizing sulfur combustion to supply heat necessary for maintaining the reaction temperature. The iron disulfide yielded has a high purity and is in a granular form having excellent handleability. It can be reduced into submicron particles by a simple disaggregating operation. The fine particles, when used, e.g., as a -51- catalyst for coal liquefaction, exhibit high activity in hydrogenation reaction to enable high-yield oil production from coal. The acid gas generating in the production is recovered as sulfuric acid and elemental sulfur respectively through oxidation and reduction. The sulfuric acid can be used for producing iron sulfate together with scrap iron or the like. Thus, a non-polluting resource-saving production process is possible in which by-products are reused as starting materials. -52-