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In this thesis, the concentration gradient method for screening soil samples were screened from multiple strains resistant to heavy metal ions and high adsorption properties of the strains. The basic characteristics of these strains were investigated, including temperature, pH, NaCl concentration and other environmental conditions on the growth of strains, strains resistant to heavy metal ions and heavy metal ions of different adsorption properties, etc., and the use of morphology and 16S rDNA gene sequence analysis and classification of isolates were identified. Ultimately pick out one pair of Ni2 better adsorption strain N-4, determine its attributable Leucobacter genus, its wholly-16S rDNA sequences in GenBank database, the sequence number is HM641755. First investigated the adsorption time on the removal of Ni2 results showed that strain N-4 to Ni2 adsorption is a fast process, during the first 10 min, the adsorption capacity of up to 80% of the maximum amount of adsorption, adsorption 40 min to to reach equilibrium. Then, the response surface method (RSM) strain N-4 affect the adsorption efficiency of the main factors: inoculation amount, pH value, Ni2 optimized concentration and optimum adsorption conditions as follows: the amount of bacteria was 5.38g / L, pH value of 4.75, Ni2 concentration of 53.6 mg / L, then the solution of Ni2 removal efficiency of up to 99%. And using Langmuir and Freundlich adsorption isotherms for the adsorption process were studied, including the Langmuir adsorption isotherm was well fitted (R2 = 0.9941), showed that strain N-4 with metal ions occurs between the monolayer. In addition, the use of false a dynamic, fake two internal diffusion kinetics and ion strain N-4 adsorption on Ni2 adsorption kinetics study showed that its fake two kinetic equation fit better. Ni2 adsorption using an infrared spectrophotometer cell before and after analysis, the results showed that the surface of the main strain containing an amide group, a carboxyl group, a phosphoric acid group and a group, wherein the hydroxyl is primary and Ni2 functional groups play a role. Finally, the strain N-4 decolorization ability studied, the results showed that the selection of the 10 different dyes have good bleaching ability. Using surface response method for strain N-4 decolorization of reactive brilliant blue KR's four main factors were optimized, the experimental results showed that strain N-4 bleaching KR optimal conditions: Wet the amount of bacteria 10g / L, dye concentration 222 mg / L, ammonium sulfate 1.5g / L, fructose, 3.5g / L, in this condition to obtain the best decolorization rate of 100%. Meanwhile, the effects of metal ions on the strain N-4 decolorization efficiency, where K, Ca2, Mg2, Ba2, Mn2 has a promoting effect on the decolorization etc., and Ni2, Cu2, Hg2 on the decolorization significantly inhibited. Further, in a certain concentration of NaCl, with the increase of NaCl concentration decolorization rate is also increased, which may be caused by the common ion effect.
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