1.
The new incorporation bio-treatment technology of bromoamine acid and azo dyes wastewaters under high-salt conditions.
Guo, J, Zhou, J, Wang, D, Yang, J, Li, Z
Biodegradation. 2008;(1):93-8
Abstract
The accelerating effect of quinones has been studied in the bio-decolorization processes, but there are no literatures about the incorporation bio-treatment technology of the bromoamine acid (BA) wastewater and azo dyes wastewaters under high-salt conditions (NaCl, 15%, w/w). Here we described the BA wastewater as a redox mediator in the bio-decolorization of azo dye wastewaters. Decolorization of azo dyes was carried out experimentally using the salt-tolerant bacteria under the BA wastewater and high-salt conditions. The BA wastewater used as a redox mediator was able to increase the decolorization rate of wastewater containing azo dyes. The effects of various operating conditions such as dissolved oxygen, temperature, and pH on microbial decolorization were investigated experimentally. At the same time, BA was tested to assess the effects on the change of the Oxidation-Reduction Potential (ORP) values during the decolorization processes. The experiments explored a great improvement of the redox mediator application and the new bio-treatment concept.
2.
Research on inhibitive behaviors of electrolysis on the growth of Microcystis aeruginosa.
Xu, YF, Yang, J, Ou, MM, Wang, YL, Jia, JP, Pan, HD
Environmental technology. 2006;(6):673-82
Abstract
Electrochemical method using a novel Ti/RuO2 anode was employed to inhibit a typical cyanobacteria, Microcystis aeruginosa (M. aeruginosa) under different electrolytic conditions. It is demonstrated that Ti/RuO2 anode was more efficient than traditional graphite anode in M. aeruginosa inhibition. The experimental results showed that the higher current density or longer electrolytic time could effectively improve the inhibition of M. aeruginosa. In addition, sodium chloride was a more effective electrolyte than sodium sulfate to enhance inhibition. The maximum inhibiting rate dose to 100% could be obtained at a current density of 12 mA cm(-2) when sodium chloride was used as a supporting electrolyte. Furthermore, UV-Visible spectra demonstrated that the structures of phycocyanins and chlorophyll a (Chl a) in M. aeruginosa could be changed or destroyed during electrolysis. Moreover, EPR spectra showed the generation of the free radicals through electrolysis, which might be one of the reasons responsible for the inhibition of algal growth.