from the conferences organized by TANGER Ltd.
Chlorinated solvents such as trichloroethene (TCE) are widespread groundwater contaminants. These contaminants can be transformed by combination of abiotic and biotic methods under anaerobic conditions. Nowadays nanoscale zero-valent iron (nZVI) is used for the treatment of chlorinated compounds via its strong reducing property. Biological reductive dechlorination of chlorinated ethenes (CEs) is contributed by dehalorespiration. The influence of nZVI in combination with carboxymethyl cellulose (CMC) and molasses on the specific dehalorespiring microflora and besides the influence of biological surface modification on reactive properties of iron was tested within this study.Groundwater contaminated with CEs was collected from the chemical factory Spolchemie a.s. Batch tests (reactors) with iron and various concentrations of CMC and molasses were performed. The samples for gas chromatography (GC) analyses were taken regularly after defined time period for determination of CEs concentration and physical-chemical parameters were monitored simultaneously. DNA was extracted after filtration of the tested water and used as a template for a real-time PCR amplification. 16S rDNA gene was used as a total bacterial community marker. Specific genes were used for detection of ongoing reductive dehalogenation (vcrA, bvcA, Dre, DHC-RT and Dsb) and to monitor denitrifying and sulphate reducing bacteria (nirK and apsA).
Keywords: Iron particles, chlorinated solvents, biological surface modification, biological reductive dechlorination, dehalorespiration, molecular genetic analysis© This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.