A Research On The Removal Of Combined Contamination Of Cr(Ⅵ) And O-dichlorobenzene In Water By S. Marcescens ZD0559

The environmental risk caused by heavy metal-organic combined pollutionhas been widely concerned. In the paper, Serratia marcesens ZD0559was isolatedfrom the sediment of tannery effluent outfalls in changsha, Hunan Province. Thedisposal methods by Serratia marcesens to simultaneously remove heavy metalsand degrade o-DCB were researched. And the reciprocities and principles of thetwo pollutants during disposal procedure were studied.Serratia marcesens ZD0559was separated and screened from the sediment oftannery effluent outfalls. Through assessing the effects of various factors,including different carbon sources, nitrogen source, temperature, pH value, ondegrading bacteria growth, biological characteristics of Serratia marcesensZD0559showed the strain could use glucose yeast extract as the optimal carbonand peptone as the nitrogen source. The strain could grow well under27℃~37℃and pH value of7.0~8.0. The strain can tolerant high concentration of Cr(VI) ando-DCB individually and simultaneously. The minimum inhibition concentrations(MIC) of Cr(VI) and o-DCB to Serratia marcesens were800mg/L and1.29g/Lrespectively. When the concentrations of Cr(VI) and o-DCB were20mg/L and1.29g/L, the removal efficiency of combined pollution was the best.The researches showed that Serratia marcesens ZD0559could degrade theo-DCB and remove Cr(VI) by biosorption and bioreduction. The removalefficiency of Cr(Ⅵ) could be affected by the initial concentration of o-DCB andCr(VI). When the initial concentration of Cr(Ⅵ) is lower than40mg/L, theremoval rate of Cr(Ⅵ) was more than80%; and when the initial concentration ofCr(Ⅵ) is higher than40mg/L, the removal rate of Cr(Ⅵ) was close to20%.Combined with GC, TEM and FTIR analysis confirmed that Serratia marcesensZD0559could remove o-DCB and Cr(VI) simultaneously. And hydroxyl, amide,polysaccharides and secreted amino acids played a leading role.