Study On Pumice Loaded Nano-zerovalent Iron And Bacillus Subtilis In Removing Phosphorus From Water

With the fast expansion of industry and the constant improvement of science and technology in recent decades,environmental contamination has become more common,and the worldwide water environmental burden has gradually grown.Phosphorus,as an essential component of life,is intricately tied to the reproduction of life on Earth.When nutrients such as nitrogen and phosphorus in a water body become oversaturated and surpass the water environment capacity that the water body can accept,it causes water eutrophication,which causes substantial harm to the ecological balance and human health.Nano-zero valent iron has steadily become a study hotspot for researchers both at home and abroad since the end of the world.Because of its advantages of large specific surface area,small particle size,strong activity,and strong reducibility,it has been widely used by many scholars in the field of environmental pollution treatment and demonstrated successful outcomes,so NZVI was used to remove phosphorus from water in this study.However,due to the faults of quick oxidation and agglomeration,NZVI’s reactivity is restricted.To increase the effectiveness of NZVI in removing pollutants,this study modified NZVI with pumice and synthesized P-NZVI to investigate the impact and mechanism of P-NZVI in synergy with Bacillus subtilis to eliminate phosphate in water.The following are the major research content and outcomes:1.P-NZVI was prepared using the traditional liquid-phase reduction method,and characterization using an environmental scanning electron microscope（SEM）revealed that the NZVI loaded with pumice effectively overcomes agglomeration defects and increases dispersibility,which is beneficial to pollutant adsorption.Transmission electron microscopy（TEM）revealed that P-NZVI had a clear core-shell structure,with a nano-iron core within and a thin oxide shell around it.The average particle size was around 30 nm,which matched the expected effect.2.Investigating the impact of several environmental conditions on synergistic phosphorus removal yielded promising findings.Phosphorus removal rate of P-NZVI is as high as 95.035%when the dosage is 30 mg,and the phosphorus removal effect under acidic conditions is better than that when the solution is alkaline;when the temperature is 25°C,P-NZVI synergistically Bacillus subtilis has the best phosphorus removal effect.3.After the reaction,the solid samples were examined using SEM,XRD,and FTIR.The analysis results showed that Fe₃（PO₄）₂·8H₂O andα-Fe O（OH）were generated after the reaction,and the mechanism of phosphorus removal by pumice nano-iron synergistically with Bacillus subtilis is mostly oxidation reaction,adsorption,chemical precipitation,and co-precipitation.