Reliable and Effective Caustic Leaching of Bauxite Samples with Rotor 20SVT50 in Multiwave 5000

Rotor 20SVT50 improves reproducible leaching of bauxite samples to simulate the industrial Bayer process over a wide range of temperatures.

Bauxite, a mixture of alumina, iron oxides, silica and a few other minerals, significantly varies from region to region. Small scale bauxite leaching is performed in the refinery laboratory to simulate the caustic leaching of the Bayer process, which is used globally for separation of pure alumina (Al2O3). The goal of this leaching is to determine the amount of “available alumina” in the bauxite ore. The amount of “reactive silica“ is normally assessed too for cost reasons, as it consumes a considerable amount of NaOH.

Depending on the composition of the ore, the temperature of the process needs to be between 150 and 240 °C. The contents of alumina and silica are traditionally determined in small-scale high-pressure steel bombs, in which it is difficult to control the heating to target temperature and to maintain it. Thus, microwave heating offers an attractive way to efficiently control the process thanks to benefits such as instant on-and-off heating and fast power input. In addition, magnetic stirring of individual reactor vessels is possible.

The parameters for this study were arbitrarily selected from the wide variety used in industry to show the reproducibility of the leaching of alumina and silicon in SVT50 high performance vessels in the microwave reaction platform Multiwave 5000. This report also addresses the extraction efficiency from bauxite ores of different origin at different temperatures.

Get the document

To receive this document please enter your email below.