Bacterial recovery and recycling of tellurium from tellurium-containing compounds by Pseudoalteromonas sp. EPR3.

Abstract

Tellurium-based devices, such as photovoltaic (PV) modules and thermoelectric generators, are expected to play an increasing role in renewable energy technologies. Tellurium, however, is one of the scarcest elements in the earth's crust, and current production and recycling methods are inefficient and use toxic chemicals. This study demonstrates an alternative, bacterially mediated tellurium recovery process. We show that the hydrothermal vent microbe Pseudoalteromonas sp. strain EPR3 can convert tellurium from a wide variety of compounds, industrial sources and devices into metallic tellurium and a gaseous tellurium species. These compounds include metallic tellurium (Te(0)), tellurite (TeO3(2-)), copper autoclave slime, tellurium dioxide (TeO2), tellurium-based PV material (cadmium telluride, CdTe) and tellurium-based thermoelectric material (bismuth telluride, Bi2Te3). Experimentally, this was achieved by incubating these tellurium sources with the EPR3 in both solid and liquid media. Despite the fact that many of these tellurium compounds are considered insoluble in aqueous solution, they can nonetheless be transformed by EPR3, suggesting the existence of a steady state soluble tellurium concentration during tellurium transformation. These experiments provide insights into the processes of tellurium precipitation and volatilization by bacteria, and their implications on tellurium production and recycling.