Research On Adsorption Of Electroplating Wastewater And Degradation Of Ciprofloxacin By Biological Manganese Oxide BMO

Biogenic manganese oxides are formed by oxidation of low valence Mn to high valence Mn by microorganisms possessing manganese oxidizing activity.In recent years,manganese oxides have been widely used in heavy metal pollution remediation and the degradation of harmful organic compounds in the environment due to their excellent adsorption and strong oxidation properties.This study uses a biological manganese oxide BMO produced by a wild strain Pseudomonas sp.T34,isolated from the soil,with high manganese oxidation activity to adsorb Ni(II)in electroplating wastewater caused for electroplating wastewater and degrade quinolone antibiotics ciprofloxacin,provides a possible solution for the heavy metal pollution and the environmental problems resulting from the abuse of antibiotics.In the adsorption experiment of electroplating wastewater containing nickel,the optimal conditions that biological manganese oxide BMO adsorbs electroplating wastewater were obtained through a series of optimization conditions: temperature50 ?,pH 4,shaking speed 200 r/min,Ni(II)concentration of electroplating wastewater 10 mg L-1.Under the optimum conditions,the adsorption kinetics of the whole adsorption process was analyzed and in agreement with the second-order adsorption kinetics characteristics.Langmuir isotherm fitting results showed that the maximum adsorption capacity is 359.71 mg g-1,and the whole process was very fast,the adsorption balance can be reached in 20 min.Through XRD,XPS,FTIR analysis,characterized and compared the changes of the BMO characterization before and after electroplating wastewater adsorption.In the 5 cycles adsorption experiment,adsorption ability of Biological Manganese Oxide BMO on electroplating wastewater can still keep 80%.In the degradation of ciprofloxacin,the optimum conditions for biodegradation of ciprofloxacin by biological manganese oxide BMO were as follows: 45 ?,pH 6,and initial concentration of ciprofloxacin was 1 ?g mL-1.Experimental results show that the metal ions can inhibit the degradation of ciprofloxacin.Through the LC-MS analysis of ciprofloxacin degradation products,has carried a preliminary identification,and put forward a possible pathway of degradation of ciprofloxacin by reference to the relevant literature.The bioassay experiments of degradation products show that biological manganese oxide BMO can significantly reduce ciprofloxacin toxicity on strain cell.4 cycles degradation experiment displayed degradation rate of ciprofloxacinremained above 90% in course.Degradation experiment in natural water shows that the possibility that biological manganese oxide BMO degrades harmful organics in the real environment.