Influence of Support Surface Properties on Activity of Bacteria Immobilised on Activated Carbons for Water Denitrification

摘要

Denitrification of water under anaerobic conditions was carried out by Escherichia coli supported or immobilised on differentrnactivated carbons and silica. Results were compared with those obtained when bacteria was used alone or mixed withrnactivated carbons. Denitrification took place in two steps: reduction of nitrate to nitrite, and its subsequent reduction torndinitrogen. The process required an external carbon source that in this case was ethanol. Results obtained in therndenitrification process were related to characteristics of activated carbon that favoured bacteria adsorption and to the finalrnpH pHPZC PZC of the activated carbon-bacteria complex. In addition, a large macropore volume also allowed the bacteria to growrnduring the process.