Dynamic simulation and experimental validation of single and multi-metallic solutions in the biosorption of heavy metals in membrane reactors: an overview

F. Pagnanellia, L. Toroa, F. Beolchinib and F. Vegliòb*

a Dipartimento di Chimica, Università degli Studi “La Sapienza”, P.le Aldo Moro, 5, 00138 Roma, Italy
b Dipartimento di Chimica, Ingegneria Chimica e Materiali, Università degli Studi di L’Aquila, 67040 Monteluco di Roio, L'Aquila, Italy

Received 27 May 2002; accepted 8 October 2002


In this paper an overview on the use of membrane reactors to immobilise micro-organisms in a stirred tank reactor during continuous heavy metal biosorption tests is presented. Experimental data were collected in different operation conditions of pH and biomass concentration both with single and binary metal solutions in membrane reactor apparatus using Sphaerotilus natans as biosorbent. A dynamic model is developed on the base of equilibrium adsorption data obtained by batch biosorption tests carried out in different operation conditions. Comparison among experimental data and simulated profiles provides the base for implementation of dynamic model as a fundamental mathematical tool in process design of continuous biosorption systems. Multi-metallic biosorption experimental data and simulations evidenced the adsorbent selectivity following the general order Pb>Cu>Cd. Multi-stage configuration allows metal removal to be increased and it is a possible alternative to separate the different metals contained in real polluted waste streams in the different stages according to their affinity for the adsorbent active sites.

Keywords: Heavy metals; Biosorption; Membrane reactor; Ultrafiltration; Microfiltration; Modelling

* Corresponding author
   E-mail : veglio@ing.univaq.it