Study On The Performance And Mechanism Of Removal Of U(?) From Water By Cellulomonas Sp

In the production of in-situ leaching uranium,the uranium pollution of groundwater has received more and more attention.Compared with the traditional physical and chemical treatment method,the biological treatment method is more environmental friendly,affordable,and highly adaptable.Thus,it inevitably has become a research hotspot for the uranium mining and metallurgy environmental governance.This study was based on Cellulomonas sp,It was verified that AQS?the electron mediators?can enhance the U???removal rate of Cellulomonas sp,elemental iron can stimulate the reduction of U???by Cellulomonas sp.By comparing the removal effect of U???of different elements,that is,?1?cell-free group?2?bacteria group?3?elemental iron group?4?bacteria The removal effect of U???by the body + elemental iron group?5?bacteria + AQS group?6?bacteria +elemental iron + AQS,the author studies the characteristics and main influencing factors of the AQS-mediated reduction of U???by the synergistic action of Cellulomonas sp and elemental iron in emphasis.Its main influencing factors:Experiments show that under anaerobic conditions,there is a significant synergistic effect of elemental iron and cellulose monocytogenes in the reduction of U?VI?.Using AQS as an electron shuttle vector,Cellulomonas sp utilizes electron donors to reduce U?VI?efficiently.Within 24 hours,when the p H was 7 and the temperature was30°C,ZVI was synergistic with Cellulomonas sp and the U?VI?removal rate was 97.6%.In the control group of elemental iron,the U?VI?removal rate was only 11.7%,while there was no reduction in U?VI?was observed in the cell-free control group.When elemental iron was not added,the removal rate of U?VI?was only 44.1% after 24 hours of reaction,while the removal rate of U?VI?added with elemental iron was above 88.5%.When the dose of ZVI was 2.0g/L,the promotion effect of ZVI to the U?VI?removal reached the limit.The coexistence of Cu2+ and Ca2+ and other ions had a significant inhibitory effect on the reduction of U???.Compared with other ions,Cr6+ and Mn2+ had less inhibitory effect.By using the transmission electron microscopy?TEM?,scanning electron microscopy?SEM?and energy dispersive spectrometer?EDS?,in addition,after the Cellulomonas sp reduced the U???,its surface has changed,which means there were many irregular protrusions formed on the surface of the bacteria and covered with uranium deposits.And the uranium element was deposited in the cells of the Cellulomonas sp.XPSresults showed that after the interaction of uranium and Cellulomonas sp,they existed as a mixture of U?VI?and U???.Through the calculation of the peak area of XPS,the contents of U???and U???were 61.9% and38.1%respectively after the interaction.And most of the uranium in the solution is stable UO₂.