From Roast to Paints
How to Use Pyrohydrolysis for Inorganic Oxide Prime Material for Ceramics
Can Nickel and Cobalt Oxides be Produced By Spray Roasting?
Ore leaching by hydrochloric acid, even at higher temperatures, is used to process Lateritic nickel ores from mines in New Caledonia, Canada. In many cases, nickel and cobalt ores are found with combinations of both elements.
There are currently experiments to determine the possibility to use spray roasting for oxides production with these materials. Currently, however, there exists only one spray roasting unit in Europe (Belgium) for the cobalt oxide production.
Special Oxides from Rare Earths — In High Demand for Electronics
The metals known as Rare Earths are mostly found in the form of sands in Australia, Brazil and South Africa. Special process designs allow a production of the corresponding chloride forms, all above the chlorine rout by a gas phase reaction, but also by leachings with hydrochloric acid solutions.
Zicnconium oxide (ZrO2) can be made starting from a solution of ZrOCl2, while yttrium oxide ,(Y2O3) relies on solutions of YCl3. Both elements can easily be used to produce the corresponding oxides at temperatures of around 800° C in a spray roaster. The resulting powder has to be be milled afterwards for further processing. This process is used in both Japan and the USA to make Y2O3 and ZrO3, which are important materials for electronics, ceramics, electro ceramics (supra conductors), catalysts, for opto electronics and for special steel processing technologies.
Dare to be Different: Alternative Spray Roasting Process Routes
All processes mentioned above are those derived from the so called hydrochloride route, which means by starting from acidic chloride salt solutions. But there are also several different routes that are currently being developed, some of them of possible future industrial importance.