Bioflocculation of Hematite and Goethite Using Bacillus licheniformis (Bio-flocculation of Hematite and Goethite)

Cells and metabolite of Bacillus licheniformis were applied in the bioflocculation of hematite and goethite. Effects of bioreagent type, pH, and solid concentration on the settling process were studied. The highest settling of hematite and goethite were obtained at pH 5 and 7, respectively. This observation was in agreement with the trend of bioflocculant adsorption. Also, among all the tested bioflocculants, bacterial cells showed the best flocculating ability. Moreover, mineral concentration and pH were determined as the most influential variables on hematite and goethite settling, respectively. Finally, all the tested bioreagents showed acceptable flocculating capabilities that were largely dependent on electrostatic forces.