Alumina Production from Clay Minerals: Current Reviews


JOURNAL OF POLYTECHNIC-POLITEKNIK DERGISI, vol.21, no.2, pp.387-396, 2018 (Journal Indexed in ESCI) identifier

  • Publication Type: Article / Review
  • Volume: 21 Issue: 2
  • Publication Date: 2018
  • Doi Number: 10.2339/politeknik.386907
  • Page Numbers: pp.387-396


Alumina (Al2O3), which is a very important material due to its superior physical and technological properties, is widely used in industry and almost all of alumina is obtained from Bayer process using bauxite as a raw material. However, some technical and economical handicaps of alumina production with Bayer process (such as limited or non availability of bauxite reserves in some countries, reduction of high grade bauxite deposits, growing alumina demand for industry etc.) require alternative raw material sources and methods to produce alumina. Therefore, investigations on the alumina production from non-bauxite sources is one of the current studies in related literature as well. Clay minerals are considered to be the best available source of non-bauxite raw material for alumina production. Because clay minerals are abundant and common in the earth crust, they have relatively high grade of aluminum, when compared to other sources, clay mining is easier and require simpler preparation and enrichment processes. There are various processes developed to produce alumina from clays, but among them "Acid Leaching Process" has become well-known method that could be practiced as a more effective method in alumina production due to some advantages. Moreover, it is seen that there is a consensus on Acid Leaching Process. Besides, there are current studies investigating several technical modifications and improvements on the process steps. The aim of this study prepared by reviewing the studies obtained from literature and current experimental results on production of alumina from clays is to give information particularly to alumina industry and stakeholders and related researchers, and to contribute to scientific studies on this topic.