Patent ID: 6056935
Filing Date: 2000-05-02
Classification: B01J,C01G,C10G

Abstract:
Iron sulfide, comprising:from 85 to 100 percent by weight FeS.sub.2,from 0 to 5 percent by weight Fe.sub.1-x S, wherein x is a number ranging from 0 to 0.2,from 0 to 5 percent by weight of Fe.sub.3 O.sub.4, andfrom 0 to 10 percent by weight of FeSO.sub.4 ;wherein said iron sulifide comprise primary and secondary particles,wherein said primary particles have a particle diameter ranging from 10 to 400 nm, andwherein said secondary particles have a 50 percent volume cumulative particle diameter ranging from 20 to 300 micrometers; andwherein said iron sulfide was formed by a process comprising the steps of:introducing an iron sulfate comprising ferrous sulfate monohydrate and at least a stoichiometric amount of at least one sulfur compound into the fluidized bed of a furnace; and thenfluidizing, burning and reacting the ingredients at a temperature ranging from 350 to less than 630.degree. C., at a superficial velocity of at least 0.1 m/sec, and at a pressure of at least 1 atm, wherein air is used as a fluidizing gas for supplying heat necessary for maintaining the reaction temperature by sulfur combustion;wherein said ferrous sulfate monohydrate has a 50 percent volume cumulative particle diameter (d.sub.50) ranging from 20 to 300 micrometers; andwherein said at least one sulfur compound is chosen from elemental sulfur in a powder, melt and vapor state and hydrogen sulfide.