Fungal biocatalyst activated by an electric field: Improved mass transfer and non-specificity for hydrocarbon degradation in an airlift bioreactor
| Autor: | Ignacio González, Keiko Shirai, Victor Sánchez-Vázquez, Mariano Gutiérrez-Rojas |
|---|---|
| Rok vydání: | 2017 |
| Předmět: |
Environmental Engineering
Health Toxicology and Mutagenesis First-order reaction 02 engineering and technology 010501 environmental sciences 01 natural sciences Fungal Proteins Bioreactors Electricity Mass transfer Alkanes Bioreactor Environmental Chemistry Petroleum Pollution Waste Management and Disposal Environmental Restoration and Remediation 0105 earth and related environmental sciences chemistry.chemical_classification Pyrenes Chromatography Chemistry Airlift Sorption Phenanthrenes 021001 nanoscience & nanotechnology Pollution Thiele modulus Kinetics Aspergillus Biodegradation Environmental Hydrocarbon Chemical engineering Emulsion Biocatalysis Thermodynamics Emulsions 0210 nano-technology Water Pollutants Chemical |
| Zdroj: | Journal of Hazardous Materials. 337:62-71 |
| ISSN: | 0304-3894 |
| Popis: | The combination of biological and electrochemical techniques enhances the bioremediation efficiency of treating oil-contaminated water. In this study a non-growing fungal whole cell biocatalyst (BC; Aspergillus brasiliensis attached to perlite) pretreated with an electric field (EF), was used to degrade a hydrocarbon blend (hexadecane-phenanthrene-pyrene; 100:1:1w/w) in an airlift bioreactor (ALB). During hydrocarbon degradation, all mass transfer resistances (internal and external) and sorption capacity were experimentally quantified. Internal mass transfer resistances were evaluated through BC effectiveness factor analysis as a function of the Thiele modulus (using first order reaction kinetics, assuming a spherical BC, five particle diameters). External (interfacial) mass transfer resistances were evaluated by kLa determination. EF pretreatment during BC production promoted surface changes in BC and production of an emulsifier protein in the ALB. The BC surface modifications enhanced the affinity for hydrocarbons, improving hydrocarbon uptake by direct contact. The resulting emulsion was associated with decreased internal and external mass transfer resistances. EF pretreatment effects can be summarized as: a combined uptake mechanism (direct contact dominant followed by emulsified form dominant) diminishing mass transfer limitations, resulting in a non-specific hydrocarbon degradation in blend. The pretreated BC is a good applicant for oil-contaminated water remediation. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect