Nanofibers for Immobilization of Microorganisms Used for Advanced Nitrogen Removal from Wastewater

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F46747885%3A24620%2F19%3A00006937" target="_blank" >RIV/46747885:24620/19:00006937 - isvavai.cz</a>

Result on the web

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DOI - Digital Object Identifier

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Result language

angličtina

Original language name

Nanofibers for Immobilization of Microorganisms Used for Advanced Nitrogen Removal from Wastewater

Original language description

Nanomaterials can be employed for immobilization of microorganisms (biofilm formation) utilizing their specific surface. With varying material compositions, preparations and modifications, the microorganisms (MO) can behave differently. For instance, MO metabolic processes can be promoted or suppressed. The properties of the nanofibrous biomass support (surface structure, wettability, charge and others) have a significant impact on the rate of microbial colonization and biofilm functionality. Bacterial strains can adapt to varying conditions according to their metabolism (nutrition). A suitably prepared and modified (physically, chemically, additively) nanomaterial can support the growth and reproduction of bacteria. There is, however, lack of studies on application of nanofibers and their modifications for preferential growth of bacteria. In this study, nanofiber carriers were prepared by direct (DC) and alternating (AC) electrospinning, using several polymers as polyvinyl butyral, polyurethane, polyamide and polyacrylonitrile. Nanofiber properties were evaluated using different methods – SEM, confocal microscopy, thermal methods, BET and respirometry. The results showed large differences in fiber morphology, surface roughness, pore size, layer homogeneity, strength, size and fiber arrangement, depending on the spinning method and polymer used. The most suitable method for preparing nanofibers with required properties was NanospiderTM, i.e. DC electrospinning. Moreover, modification of PVB nanofibers through addition of Fe3O4 nanoparticles showed as a very promising option for biotechnological applications, particularly for growth of specific bacteria (for example for nitrifying and denitrifying bacteria). The PVB nanofibers doped by Fe3O4 nanoparticles were tested in a lab-scale bioreactor, and the results were unexpected. Respirometric tests showed approximately 2 times higher bacterial activity during the ammonia nitrogen removal when using composite carriers compared to activated sludge. In addition, large number of nitrifying bacteria was detected on these carriers by FISH analysis. Nanoparticles Fe3O4 inside PVB polymer allow efficient binding of ammonia nitrogen to the carrier (biofilm) [2], thereby accelerating its removal. Applying these materials would increase the efficiency of removing nitrogen related substances from water without major modifications to existing plants.

Czech name

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Czech description

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Type

O - Miscellaneous

CEP classification

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OECD FORD branch

20801 - Environmental biotechnology

Project

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Continuities

S - Specificky vyzkum na vysokych skolach

Publication year

2019

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů