Effect of specific inhibitors on the anaerobic reductive dechlorination of 2,4,6-trichlorophenol by a stable methanogenic consortium.

The transformation of 2,4,6-trichlorophenol (TCP) into 4-chlorophenol (4CP) was studied using a stable methanogenic enrichment culture derived from an anaerobic fixed bed reactor. Using acetate as a growth substrate, different inhibitors of methanogenesis exhibited distinct effects on TCP dechlorination. Whereas reductive dechlorination activity was not affected by 2% ethylene in the gas phase, 25 mM bromoethanesulfonic acid (BESA) had a direct inhibitory effect on this process.

A tanks-in-series bioreactor to simulate macromolecule-laden wastewater pretreatment under sewer conditions by Aspergillus niger.

Sewers are typically a means of transporting wastewater to a treatment facility, with little biotransformation of the soluble polymeric organic matter by suspended biomass. In the interest of providing an effective pretreatment of wastewater in a sewer network, it is necessary to design an accurate tool simulating sewer conditions and introduce an appropriate biomass for macromolecular pollutant degradation. Such a model reactor was built using a tanks-in-series design and the degradation of a polysaccharide (starch) by Aspergillus niger MUCL 28817 was studied.

Abiotic transformation of catechol and 1-naphthol in aqueous solution-influence of environmental factors.

The abiotic transformation of catechol and 1-naphthol singly and in mixtures was tested in sterile Tris-HCl buffer with regard to several environmental factors including temperature (7 degrees C, 20 degrees C and 30 degrees C), lighting conditions, pH (between 7.0 and 8.5) and dissolved oxygen (at partial pressures of 0.

Glutathione-mediated mineralization of 14C-labeled 2-amino-4,6-dinitrotoluene by manganese-dependent peroxidase H5 from the white-rot fungus Phanerochaete chrysosporium.

Manganese-dependent peroxidase (MnP) H5 from the white-rot fungus Phanerochaete chrysosporium, in the presence of either Mn(II) (10 mM) or GSH (10 mM). was able to mineralize 14C-U-ring-labeled 2-amino-4,6-dinitrotoluene (2-A-4,6-DNT) up to 29% in 12 days. When both Mn(II) and GSH were present, the mineralization extent reached 82%.

Pressure-drops control strategy in a fixed-bed reactor.

This paper presents a strategy to control pressure-drops (head loss) in a biofilter designed according to the "Mist-Foam" concept. This concept is based on the mixing of the gaseous substrate and a liquid nutrient solution with an atomization nozzle to generate a mist passing subsequently through a synthetic polyurethane foam. In this type of bioreactor, the microbial growth reduces progressively the empty bed volume of the biofilter and causes an increase in the pressure-drops.