| It is becoming hot research of microorganism and clay mineral, which are as new styles material for contaminate environmental remediation, because of their low-cost, abundant stocking and some other properties. In this research, the influence of bacteria to clay mineral surface characteristics and it sorption performance were discussed on the basic of bacterium with resistance to manganese loaded modified clay mineral. The main conclusions of the paper obtained were listed as follows:1. A bacteria strain of M-2, which was isolated, screened from the area with high manganese contaminated and could remove away 95% manganese ions from aqueous solution, were studied. Based on its morphology, physiological and biochemical characters, as well as 16S rDNA sequence analysis, the bacteria strain M-2 identified as Bacillus subtilis.2. The influence of various factors to adsorption for the bacteria strain M-2 by clay mineral had been discussed. The experimental data indicated that: (1) The adsorptive quantities of M-2 were largely determined by different kinds of clay mineral. (2) With increasing contact time, the adsorptive saturation point of M-2 using diatomite appeared at 30min, and 60min using zeolite; (3) The adsorption capacity of M-2 increased with temperature, and got the maximal dot at 40℃, then, descended when temperature still ascended; Also, the adsorption capacity of M-2 slightly increased when pH was raised from 3.5 to 6.5, then, descended when pH still ascended.3. The surface properties of clay mineral with the bacterial stain M-2 in the reaction system.would be affected. pHzpc and surface area for diatomite and the compound of diatomite-bacteria were 6.2,5.8, 85.3m2·g-1 98.2 m2·g-1 respectively, while that for zeolite and the compound of zeolite-bacteria were3.8,4.9, 141.9 m2·g-1,160.5 m2·g-1 respectively. 4. To get the same maximal adsorption rate(>80%), the using dose of compound sorbents were less then that of single clay mineral, while the using dose of diatomite's higher then that of zeolite's; The adsorption rate of Mn(Ⅱ) increased with temperature upping; and also, The adsorption rate with higher pH in aqueous solution was higher. However, it descended when pH>8.6. In the whole reaction, the compound sorbent was higher availability then single clay mineral.5. The experimental data fitted Langmuir's model perfectly. The maximal adsorption capacity, Qmax and equation constant K, grew 24%,23% respectively for the compound of clay-mineral. Increasing of Langmuir's model constant K, which represented the affinity of sorbent for sorbate, meant the affinity of clay mineral for manganese was stronger in the system with bacteria. Additionally, Pseudo-second-order rate equations were found to satisfactorily describe manganese adsorption kinetics using clay mineral and the compound of clay mineral-bacteria. This meant there was chemical reaction in the process. Furthermore, As compared to Ea for diatomite, diatomite-bacteria, zeolite and zeolite-bacteria respectively, however, the process was not only a simple chemical reaction, but also physical sorption, that was liquid membrane diffusion.
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