Influence of the addition of sulphate and ferric ions in a methanogenic anaerobic packed-bed reactor treating gasoline-contaminated water

Benzene, toluene and xylene (BTX) are relatively soluble aromatic compounds of gasoline. Gasoline storage tank leakages generally lead to an extensive contamination of groundwater. In the natural environment for instance, these compounds might be biodegraded under a variety of reducing potentials. The objective of this work was to examine the influence of the addition of sulphate and Fe(OH)3 in a methanogenic horizontal-flow anaerobic immobilized-biomass reactor treating gasoline-contaminated water. Three different conditions were evaluated: methanogenic, sulphidogenic and sulphidogenic with the addition of ferric ions. Methanogenic condition showed the higher BTX degradation rates and the addition of sulphate negatively affected BTX removal rates with the production of H2S. However, the addition of ferric ions resulted in the precipitation of sulphur, improving BTX degradation by the consortium. Metanosphaera sp., Methanosarcina barkeri and Methanosaeta concilii were identified in the consortium by means of 16S and directly related to the addition of ferric ions.

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Development of a bioreactor system for the remediation of endosulphan

H2Open Journal ◽

10.2166/h2oj.2019.018 ◽

2018 ◽

Vol 2 (1) ◽

pp. 1-8 ◽

Cited By ~ 1

Author(s):

K. Jesitha ◽

P. S. Harikumar

Keyword(s):

Detection Limit ◽

Calcium Alginate ◽

Packed Bed ◽

Alginate Beads ◽

Soil Samples ◽

Packed Bed Reactor ◽

Contaminated Water ◽

Initial Concentration ◽

Bioreactor System ◽

Ca Alginate

Abstract A bioreactor system that consisted of Pseudomonas fluorescens cells immobilised in calcium-alginate beads was utilised to remediate endosulphan contaminated water and soil. A packed bed reactor system was designed for the bio-degradation of endosulphan in artificially spiked water samples (initial concentration of endosulphan: 350 µg/L). Reactor studies with cell-immobilised Ca-alginate beads were conducted after checking their efficiency through batch and column degradation studies. The results showed that the concentration of toxic isomers of endosulphan (endosulphan alpha and endosulphan beta) was below the limit in the bioreactor during the 7th day of the experiment. Experiments conducted with contaminated soil samples (initial concentration of endosulphan: 1,000 μg/kg) indicated that the toxic isomers of endosulphan degraded to below the detection limit within 10 days and monitoring of endosulphan residues on the 14th day revealed that almost complete degradation of metabolites of endosulphan had occurred. The bioreactor system designed can be scaled up for remediation of endosulphan in contaminated areas.

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Photocatalytic Active Coatings for Lignin Degradation in a Continuous Packed Bed Reactor

International Journal of Photoenergy ◽

10.1155/2014/502326 ◽

2014 ◽

Vol 2014 ◽

pp. 1-10 ◽

Cited By ~ 6

Author(s):

Colin Awungacha Lekelefac ◽

Johannes Hild ◽

Peter Czermak ◽

Michael Herrenbauer

Keyword(s):

Photocatalytic Degradation ◽

Solid Phase ◽

Sol Gel ◽

Packed Bed ◽

Reaction Rates ◽

Packed Bed Reactor ◽

Dissolved Carbon ◽

Degradation Rates ◽

Vis Spectroscopy ◽

Lignin Sulfonate

The synthesis of immobilized catalyst on porous glass support material via the sol-gel route is reported. TiO2-P25-SiO2+ Pt, TiO2-P25-SiO2, TiOSO4_30.6 wt%, and ZnO + TiO2-P25-SiO2catalysts were synthesized and a comparative study is done regarding morphology of coatings, degradation rates, reaction rates, dissolved carbon (DC), formation of peaks, and fluorescence of products formed from the photocatalytic degradation of lignin sulfonate obtained from a local paper plant. Through simultaneous reaction-extraction pathways applying dialysis filtration and highly porous polystyrene divinylbenzene adsorbent resin (HR-P) for solid phase extraction (SPE), an attempt has been made to isolate smaller molecules produced from photocatalytic degradation. Moreover relatively high lignin sulfonate (0.5 g/L) concentrations are used in the reactions. UV-Vis spectroscopy revealed a faster reduction in the concentration values for the aliphatic moiety compared to the aromatic moiety. Peaks were observed by both fluorescence spectroscopy and HPLC suggesting the production of new substances and fluorophores.

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Gene Expression during BTEX Biodegradation by a Microbial Consortium Acclimatized to Unleaded Gasoline and a Pseudomonas putida Strain (HM346961) Isolated from It

Polish Journal of Microbiology ◽

10.5604/01.3001.0010.7836 ◽

2017 ◽

Vol 66 (2) ◽

pp. 189-199 ◽

Cited By ~ 3

Author(s):

Jesús A. Morlett Chávez ◽

Jorge Á. Ascacio Martínez ◽

William E. Haskins ◽

Karim Acuña Askar

Keyword(s):

Gene Expression ◽

Pseudomonas Putida ◽

Aromatic Compounds ◽

Microbial Consortium ◽

Protein Sequences ◽

Environmental Applications ◽

Contaminated Water ◽

Unleaded Gasoline ◽

Great Capacity ◽

Benzene Toluene

Pseudomonas putida strain (HM346961) was isolated from a consortium of bacteria acclimatized to unleaded gasoline-contaminated water. The consortium can efficiently remove benzene, toluene, ethylbenzene and xylene (BTEX) isomers, and a similar capability was observed with the P. putida strain. Proteome of this strain showed certain similarities with that of other strains exposed to the hydrocarbon compounds. Furthermore, the toluene di-oxygenase (tod) gene was up-regulated in P. putida strain when exposed to toluene, ethylbenzene, xylene, and BTEX. In contrast, the tod gene of P. putida F1 (ATCC 700007) was up-regulated only in the presence of toluene and BTEX. Several differences in the nucleotide and protein sequences of these two tod genes were observed. This suggests that tod up-regulation in P. putida strain may partially explain their great capacity to remove aromatic compounds, relative to P. putida F1. Therefore, new tod and P. putida strain are promising for various environmental applications.

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Anaerobic degradation of BTEX in a packed-bed reactor

Water Science & Technology ◽

10.2166/wst.2002.0323 ◽

2002 ◽

Vol 45 (10) ◽

pp. 175-180 ◽

Cited By ~ 17

Author(s):

I.R. de Nardi ◽

M.B.A. Varesche ◽

M. Zaiat ◽

E. Foresti

Keyword(s):

Anaerobic Degradation ◽

Experimental Period ◽

Packed Bed ◽

Packed Bed Reactor ◽

Most Probable Number ◽

Probable Number ◽

Anaerobic Microorganisms ◽

Sequential Experiments ◽

Benzene Toluene ◽

Anaerobic Biomass

A bench-scale horizontal-flow anaerobic immobilized biomass (HAIB) reactor was assayed aiming to verify its performance in degrading benzene, toluene, ethylbenzene and xylene (BTEX). A 138-ml HAIB reactor filled with polyurethane foam matrices containing immobilized anaerobic biomass was initially fed with synthetic substrate containing protein, carbohydrates and lipids. Thereafter, BTEX degradation was evaluated in the presence of the co-solvents ethanol and lineal alkylbenzene sulphonate (LAS), in two sequential experiments. The inlet BTEX concentration ranged from 1.3 to 27.0 mg/L of each compound and outlet concentrations were lower than 0.1 mg BTEX/L for both the experiments with ethanol and LAS. An active enriched microbial consortium was observed in the reactor, containing BTEX-degraders, and also acetogenic, acetotrophic and hydrogenotrophic microorganisms. The results from the most probable number (MPN) tests indicated a decrease in the number of methanogenic archae, while the number of anaerobic microorganisms in the biofilm was maintained during the experimental period. Methanogenic archae were found to represent less than 0.5 % of the total anaerobic organisms in the biomass inside the reactor.

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Influence of multiple substrates on anaerobic protein degradation in a packed-bed bioreactor

Water Science & Technology ◽

10.2166/wst.2003.0349 ◽

2003 ◽

Vol 48 (6) ◽

pp. 23-31 ◽

Cited By ~ 17

Author(s):

G. Tommaso ◽

R. Ribeiro ◽

M.B.A. Varesche ◽

M. Zaiat ◽

E. Foresti

Keyword(s):

Kinetic Model ◽

Protein Degradation ◽

Packed Bed ◽

Packed Bed Reactor ◽

Order Kinetic ◽

First Order ◽

Multiple Substrates ◽

Degradation Rates ◽

Order Kinetic Model ◽

Parallel Reactions

Data on the influence of substrate composition on the anaerobic degradation of bovine serum albumin (BSA) in a bench-scale packed-bed reactor are presented and discussed from the standpoint of substrate consumption kinetics. The experiments were carried out in a horizontal-flow anaerobic immobilized biomass (HAIB) reactor fed with BSA based substrates. BSA was the sole carbon source in the first one, while the others were composed of BSA, carbohydrates and lipids. In all the experiments, the HAIB reactor was operated at the hydraulic detention time of 4 hours. The reactor's performance was evaluated based on physicochemical and chromatographic analyses and also on microscopy techniques. A kinetic model of irreversible first-order series-parallel reactions with two intermediate products was proposed, allowing evaluation of the microbial consortiumÕs affinity with the substrates and the metabolic compounds formed. As the first-order kinetic model adhered quite well to the experimental data, the initial protein degradation rates (k) were estimated. The presence of carbohydrates and lipids led the initial protein degradation rate to be reduced. However, the system fed with protein and carbohydrates showed higher process stability.

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