Biosorption of toxic metals by immobilised biomass and UF/MF membrane reactor

摘要

A study on the biosorption of toxic metals (copper, nickel and lead) by a species of Arthrobacter sp. bacterium is reported in this work. Arthrobacter sp was tested as a biosorbing material free in solution and immobilised in a polymeric matrix of poly-hydroxoethylmethacrylate. The equilibrium of the process was in all cases well described by the Langmuir isotherm. In the case of immobilised biomass, the Shrinking Core Model has been used for the fining of experimental data. A good fit has been found in the case of controlling intraparticle diffusion in all experimental trials. A membrane process represents an alternative to immobilisation in polymeric matrices, which might be too expensive. A simulation has been performed by combining equilibrium data obtained in equilibrium biosorption trials and material balances in a membrane module. The simulation showed the technical feasibility of the biosorption process where biomass is confined inside the reactor by an appropriate membrane.