In early September, the team of BiotaTec had an exciting chance to visit the Laboratory of Metallurgy at The National Technical University of Athens.
The visit also included a meeting with Mr Efthymios Balomenos, a Senior Researcher at the Raw Materials Exploitation & Sustainable Energy Solution.
Major topic covered at the meeting was naturally Greek Bauxite Residue – a by-product of alumina production with the Bayer process by which alumina (Al2O3) is produced from bauxite ore. In the given hydrometallurgical process, caustic soda digestion under elevated temperature and pressure is used to leach soluble alumina minerals and subsequently precipitate technically pure aluminum hydroxide. The residual mineral matrix named Red Mud or Bauxite Residue is removed as a by-product from the pregnant leach solution.
Global annual production of bauxite residue is estimated to be about 150 Mt (Evans, 2016).
We are glad to report that preliminary tests with Bauxite Residue have already started in our lab. Can our bioleaching be here as effective as in case of valorizing other tailings and wastes – well, we will know more in a couple of months.