Li Q.,Jinan University |
Li Q.,Key Laboratory of Water Soil Toxic Pollutants Control and Bioremediation |
Liu Y.,Jinan University |
Du Y.,Jinan University |
And 4 more authors.
Chemosphere | Year: 2011
Many of the coastal tidal flats in China that were polluted with heavy metals are now being reclaimed for arable land. The safety of these soils for agriculture is of great concern. The present study investigated the sediment chemical properties, concentrations, and speciation of heavy metals at different levels of desalination during a controlled leaching experiment. After leaching with fresh water, the average reductions in the heavy metal species examined in 0-65. cm depth sediment were 32.1% for Pb, 26.2% for Cd, 14.0% for Zn, 13.8% for Cu, and 11.0% for Cr, while the Ni concentration in sediment did not change significantly. The amounts of Cd, Pb, Cr, Cu, and Zn bound to the reducible fraction, the amounts of Cd, Pb, and Zn bound to the exchangeable fraction, the amounts of Pb, Cr, Cu, and Zn associated with the carbonate fraction, and the Cu associated with the oxidizable fraction all decreased significantly. Complexation with salt anions, ion exchange between the cations and the metal ions, removal of SO42-, dissolution of carbonate, and the redox potential variations all contributed to the decreases in Pb, Cd, Zn, Cu, and Cr. These results suggest that leaching with fresh water can also remove a fraction of the heavy metal contamination when it diminishes sediment salinity. © 2010 Elsevier Ltd.
Liao J.,Jinan University |
Liao J.,Key Laboratory of Water Soil Toxic Pollutants Control and Bioremediation |
Jin L.,Jinan University |
Jin L.,Key Laboratory of Water Soil Toxic Pollutants Control and Bioremediation
Chinese Journal of Environmental Engineering | Year: 2015
Activated carbon fiber bio-film curtain with dynamic auxiliary was used to simulate the polluted source water in situ restoration. The effects of different temperatures and initial ammonia nitrogen concentrations on the remediation were discussed. The results indicated that the middle temperature was advantageous to the microorganisms on the biodegradation of organic matter and ammonia nitrogen, and low temperature was more conducive to microbial phosphorus removal. At 35℃, the removal efficiencies of CODMn and NH3-N were the best, 90% and 94%, respectively, whereas the highest removal rate of TP could reach 54% at 15℃. Under the different ammonia nitrogen concentrations (1.27,1.68 and 2.54 mg/L),the removal efficiency of CODMn was good and stabilized at approximately 85%. With the increase of initial ammonia nitrogen concentrations, the removal efficiency of NH3-N and TP decreased gradually. The removal rate of NH3-N reduced from 96% to 92%, while the removal rate of TP reduced from 40% to 30%. ©, 2015, Science Press. All right reserved.
Chen L.-L.,Jinan University |
Chen L.-L.,Key Laboratory of Water Soil Toxic Pollutants Control and Bioremediation |
Jin L.-H.,Jinan University |
Jin L.-H.,Key Laboratory of Water Soil Toxic Pollutants Control and Bioremediation
Zhongguo Huanjing Kexue/China Environmental Science | Year: 2014
As to characteristics of the nonlinearity of water body eutrophication evaluation system, the randomness of weight assignment and inaccuracy of subordinate function during the process of fuzzy comprehensive evaluation, an improved fuzzy comprehensive evaluation method has been pointed out through improving the traditional fuzzy comprehensive evaluation method, and it has been applied to evaluate degrees of eutrophication of water body in 24representative lakes and reservoirs in China. During the process of improvement, the analytic hierarchy process was combined with principal component analysis by software SPSS16.0 and Yaaph to determine index weights, and the determined evaluation criteria were logarithmically transformed to linear, and also each index membership function of logarithmic and lower semi-trapezoid form corresponding to every trophic levels was generated based on distribution characteristics of detected field data, then the membership degree of each lake or reservoir can be obtained and its eutrophication level can be determined by the principle of maximum membership degree. The result of the improved method has been compared with actual eutrophication status of lakes or reservoirs and evaluated results obtained by present evaluation methods, which shows that the calculating process of the improved method is simple, and its result is true and accurate, thus the method is feasible and practical. ©, 2014, Chinese Society for Environmental Sciences. All right reserved.
Song L.,Jinan University |
Song L.,Key Laboratory of Water Soil Toxic Pollutants Control and Bioremediation |
Zhang X.,Jinan University |
Zhang X.,Key Laboratory of Water Soil Toxic Pollutants Control and Bioremediation |
And 2 more authors.
Reaction Kinetics, Mechanisms and Catalysis | Year: 2011
Polymer-modified TiO2 was found to be a new, efficient photocatalyst for the photodegradation of organic pollutants. Another novel sensitizer-poly(fluorene-co-bithiophene) (PFB) was presented in this study. Varying the bithiophene content of PFB from 10, 20, 33, 40 to 50% in molar ratio, a series of copolymers (PFB10, PFB20, PFB33, PFB40 and PFB50) were prepared and used as the sensitizers for TiO2. The photodegradation rates of phenol catalyzed by these polymer-modified titanium dioxide composites under the irradiation of the GaN LED clusters were investigated. It was found that PFB33-modified TiO2 was the most efficient photocatalyst although the absorption spectrum of PFB50 was broader than that of PFB33. © 2011 Akadémiai Kiadó, Budapest, Hungary.
Liu Y.,Jinan University |
Liu Y.,Key Laboratory of Water Soil Toxic Pollutants Control and Bioremediation |
Li M.,Jinan University |
Li M.,Key Laboratory of Water Soil Toxic Pollutants Control and Bioremediation |
And 4 more authors.
Chemistry Bulletin / Huaxue Tongbao | Year: 2011
The removal of cyanide from micro-polluted waters by K2FeO 4 was studied. The effect of pH, temperature, reaction time, dosage of Ferrate (VI), initial cyanide concentration on the cyanide removal was investigated and the mechanism of cyanide removal was discussed. The results showed that, within the pH ranges of 7 ∼ 10. 5 , the removal efficiency of cyanide increased as the pH became larger, while the effect of temperature was not obvious. Under the condition that the pH =9. 0, the oxidation time is 10min, and the initial cyanide concentration is 0. 25mg/L in the raw water, 2. 5mg/L (K2FeO4= CN- = 10: 1 ) ferrate( VI) can reduce the residual concentration of cyanide to lower than 0. 05mg/L, which satisfied the requirement of water quality standard for " drinking water health standards" (GB 5749 -2006). Changing the initial concentration of cyanide, the dosage of ferrate(VI) should be raised to keep high removal efficiency of cyanide.