ANew Low-Temperature Preparations of Some Simple and Mixed Co and Ni Dispersed Sulfides and Their Chemical Behavior in Reducing Atmosphere

A series of simple (...) and mixed sulfides ... was prepared using low-temperature procedures. To obtain the mixed sulfides, the mixtures of the solutions of the corresponding salts were precipitated by Na28 and then heated in a sulfiding atmosphere at 300 °C. It has been found that the product phase composition depends on the sulfiding atmosphere. Using a h2S/Ar mixture leads to pyrite type sulfides, whereas treatment in H2S/H2 flow allowed the preparation of Ni-Co and Cu-Co thiospinels. The as prepared highly dispersed single-phase materials were characterized by X-ray powder diffraction, scanning electron microscopy, temperature-programmed reduction (TPR), elemental analysis, and BET surface area measurements.