Influence of biofouling on pharmaceuticals rejection in NF membrane filtration.

The effects of biomass attachment and growth on the surface characteristics and organic micropollutants rejection performance of nanofiltration membranes were investigated in a pilot installation. Biomass growth was induced by dosing of a readily biodegradable carbon source resulting in the formation of a biofouling in the investigated membrane elements. Surface properties and rejection behaviour of a biofouled and virgin membrane were investigated and compared in terms of surface charge, surface energy and hydrophobicity.

Surface characterisation of biofouled NF membranes: role of surface energy for improved rejection predictions.

Biomass attachment and growth on high pressure membranes alter the surface characteristics and rejection performance of nanofiltration membranes. Along with electrostatic interaction and size exclusion, hydrophobic interaction between solutes and membrane surface play the major role in the separation process. Therefore, in attempt to properly quantify the surface energy of clean and biofouled membranes, different contact angle techniques were applied in this research.

Dominance of Geobacteraceae in BTX-degrading enrichments from an iron-reducing aquifer.

Microbial community structure was linked to degradation potential in benzene-, toluene- or xylene- (BTX) degrading, iron-reducing enrichments derived from an iron-reducing aquifer polluted with landfill leachate. Enrichments were characterized using 16S rRNA gene-based analysis, targeting of the benzylsuccinate synthase-encoding bssA gene and phospholipid fatty acid (PLFA) profiling in combination with tracking of labelled substrate. 16S rRNA gene analysis indicated the dominance of Geobacteraceae, and one phylotype in particular, in all enrichments inoculated with polluted aquifer material.

Degradation of BTX by dissimilatory iron-reducing cultures.

The ability of indigenous bacteria to anaerobically degrade monoaromatic hydrocarbons has received attention as a potential strategy to remediate polluted aquifers. Despite the fact that iron-reducing conditions are often dominating in contaminated sediment, most of the studies have focussed on degradation of this class of pollutants with other terminal acceptors. In this work, we enriched bacteria from an iron-reducing aquifer in which a plume of pollution has developed over several decades and we show that benzene, toluene, meta- and para-xylene (BTX) could be degraded by the enriched cultures containing intrinsic iron-reducing microorganisms.

Degradation of btex compounds under iron-reducing conditions in contaminated aquifer microcosms.

The potential for benzene, toluene, ethylbenzene, and xylenes (BTEX) degradation was investigated in microcosms inoculated with sediment and groundwater from a polluted iron-reducing aquifer. Benzene, toluene, and each of the three xylene isomers were degraded by the intrinsic microorganisms under iron-reducing conditions, but there was no removal of ethylbenzene. This work provides the first evidence for para-xylene degradation by dissimilatory iron-reducing bacteria.