The combination of biosorption and bioprecipitation together with the knowledge of parameters determining these processes can allow to design new metal removal systems. In case of environmental applications all metals can be removed by biomass with no specificity. But in case of recycling activities highly selective biomass can be chosen. The use of viable biomass can lead to the formation of highly crystalline material with a high metal to biomass ratio (> 10). This will give rise to the recycling of metal ions or complexes into new crystals or minerals.
The aim of this work is to come to high up concentration rates of heavy metals in a bacterial way. In this way a system can be developed for a better removal and recuperation of heavy and/or precious metals with a higher upconcentration rate (between 50 and 100 %) than the existing methods. To obtain this, a model will be constructed by taking into account the GENETIC (genes coding for heavy metal resistance, for metal binding proteins and for siderophore production), BIOCHEMICAL (metal binding proteins, enzyme activity, secondary metabolites), CELLULAR (cell charge, functional groups, polymers) and MICROENVIRONMENTAL (pH gradient, extracellular polymers, redox potential, ionic composition and concentrations) parameters which will determine bacterial SORPTION and MINERALIZATION processes.
The model will be build on a few bacterial biomineralization systems which are already under study by different partners. With the model we will verify if this system can be extended to other bacteria and to other metals which will be of economic importance.
The model will help the researchers to extend biosorption (5 to 10 % of metal bound per biomass) to biomineralization (more than 50 % of metal per biomass). In this way bacterial processes will become very interesting for heavy metal removal and recovery in different industries. The presented study will be the first time that a problem will be approached in a global way by the different capacities of the partners.
Funding SchemeCSC - Cost-sharing contracts
RG4 9NH Reading