Preparation of cobalt titanates via co-precipitation while using industrial intermediates as titanium precursors

Abstract

This paper reports on the results of cobalt titanates preparation by calcination of green bodies obtained by a co-precipitation method. For the investigations were used: as titanium sources, acidic solutions of titanyl sulfate and hydrous titanium dioxide, originating from the production process of titanium dioxide by sulfate method. The composition of the obtained materials was determined using titration methods. The calcined powders were characterized by X-ray diffraction method. It has been found that the obtained products are composed of cobalt methatitanate CoTiO 3 or cobalt orthotitanate Co 2 TiO 4 occurring as single phases, and also as cobalt titanates and titanium dioxide phase mixtures. The proposed method of proceeding can be used for the preparation of series of transition metals titanates, such as nickel, iron, zinc, copper and also aluminium titanates.

High temperature oxidation resistance of (Ti,Ta)(C,N)-based cermets

“…At higher temperatures (1000 ºC and 1100 ºC) (figure 4), when the oxidation has significantly progressed, TiO2 emerges at the surface of the cermet, while cobalt oxides disappear by reacting with TiO2 rutile to form cobalt methatitanate (CoTiO3) or cobalt orthotitanate (Co2TiO4, cubic structure, Fd-3m, 227), according to reactions (2-5), as follows [22,23] It is possible to consider the formation of Co2TiO4 from CoTiO3, according to the following reaction (6):…”