Polychlorinated biphenyls (PCBs), Polychlorinated phenols (PCPs) phenols and their derivatives are a group of chemicals now considered among the most hazardous pollutants in the world. The presence of these extremely stable compounds in trace concentrations in water have been linked to an increased risk in frequency of cancer. PCBs were used for production of various industrial capacitors, pesticides and herbicides over a number of years. PCPs and chlorophenols are used as precursor in the production of preservative and dyestuffs, additionally phenol and its derivatives are still produced as a side product of oil refinery and chlorination of water, therefore these toxic compounds are present and still appear in ground and water.
Existing multistep water purification processes for PCBs, PCPs and other chlorinated contaminants are expensive, mostly due to usage of different chemicals. Bioremediation processes utilising bacteria represents an alternative to existing chemical methods. Immobilisation of bacteria on a substrate has a number of benefits over free bacteria suspension, such as higher biomass content, even distribution in volume, high metabolic activity and resistance to toxic chemicals, which results in a continuous process operating and avoiding the biomass-liquid separation restrictions. The immobilised bacteria can be reused several times opening opportunities for developing cost-effective processes for wastewater treatment. In this project, we apply a cutting-edge technology; he developed the direct cross-linking of the bacteria cells into a 3D-structured macroporous, highly permeable system. This system is used for selective and efficient purification of contaminated water from phenols, cresols and its chloro derivatives (chlorophenols etc.).
Advantages of the novel system are:
- one step immobilisation and high density of immobilised cells
- no diffusion restriction of contaminant to the cells and the possibility of exploiting the system as a flow through bioreactor.
This is an inter- and intra-disciplinary project involving the combination of knowledge and expertise in microbiology, cryotechnology, organic, polymer, physical, analytical, environmental and surface chemistry. The project intends to solve sophisticated problems of environmental remediation through the combination of microbiology and polymer chemistry.
Illustration of microporous structure of the 3D-cryo bacteria reactor composed of cross-linked bacteria and its possibility to consume toxic and mutagenic contaminants (phenols, cresols, mono & polychlorophenols) from water as a source of energy.