An evaluation of equilibrium and kinetic models for gold biosorption

Abstract

Biosorption of gold by a novel biosorbent, GOLDBIOSORB, prepared from a dead macro fungus has been investigated. GOLDBIOSORB showed high uptake capacity for gold ions. Both equilibria and kinetics of biosorption have been studied and several mathematical models have been evaluated. It was found that models with a higher number of parameters did not provide better correlation than the commonly employed Freundlich and Langmuir isotherms. Evaluation of process kinetics using different models has brought about a better understanding of overall transport of sorbate onto the biosorbent. This study showed that both pore- and film-diffusion are significant in the biosorption of gold by the biosorbent.