Attachment behaviour of Thiobacillus ferrooxidans cells to refractory goldconcentrate particles

In the biooxidation of minerals, cells of Thiobacillus are distributed betw een the surface of the particles and the liquid. This work quantifies the k inetics of attachment, the equilibrium between attached and suspended cells , and the influence of ferric ion and particle size on this phenomenon. The attachment kinetics were fast, the equilibrium was reached in 10 to 30 min utes, depending on the initial population. The equilibrium curves showed th ree distinct phases, and the first two could be modelled by Langmuir equati ons. The maximum concentration of attached cells increases with the additio n of ferric ions and decreases with particle size.