Study On Removal Of Organic Pollutants By Kiwi Branch Biochar

Biochar has a rich pore structure and functional groups,and its cost is low and the raw materials are wide.Research on the adsorption of biochar to pollutants has become one of the current research hotspots in environmental chemistry,but the research on the adsorption and removal of pollutants under dynamic flow is still in a blank stage.In this paper,the kiwi branch is used as the representative of biomass.At 700?,pyrolysis is used to prepare biochar.First,the prepared biochar is subjected to scanning electron microscopy.Secondly,the adsorption performance of biochar on the antibiotic antibiotic amoxicillin and the cationic dye methylene blue is studied.;Finally,the dynamic adsorption process of amoxicillin and methylene blue under different physical and chemical conditions through the use of filter sand column for the dynamic adsorption process of amoxicillin and methylene blue under different physical and chemical conditions;The influence of charcoal on the removal behavior of amoxicillin and methylene blue in the environment has important theoretical and practical guiding significance for the application of biochar.The main conclusions are as follows:?1?Research on biochar adsorption of organic pollutantsAt 700?,kiwi branch was cracked by high temperature tube furnace to produce kiwi biochar?BC?;SEM results showed that there were many tiny pores inside and on the surface of BC.The kinetic model of methylene blue?MB?conforms to the quasi-second-order kinetic model,indicating that the adsorption of biochar to amoxicillin and methylene blue is a physical-chemical composite process,and the fitting degree of Langumir equation of isothermal adsorption?R²>0.99?is obvious Higher than the Freundlich equation,indicating that the adsorption process of BC to amoxicillin?AMX?and methylene blue?MB?is monolayer adsorption.The adsorption capacity of BC for AMX and MB was 6.53 mg g^-1and 11.56 mg g^-1,respectively.?2?Effect of biochar filling on the dynamic removal of amoxicillinThe removal effect of quartz sand on AMX is little affected by physical and chemical factors.The experimental results show that the outflow rate of AMX in the sand column is very strong.Among them,changes in p H,IS,and flow rate will not affect its outflow.The recovery rate remained basically above 95%.When the sand column is filled with BC,the results of the AMX dynamic removal experiment show that the presence of BC in the sand column significantly hinders the outflow of AMX.The more the BC is filled,the more obvious the interception effect on AMX is.When the p H changes,the outflow of AMX will also change,of which p H=7 is the most unfavorable for the outflow of AMX;the ionic strength after biochar filling has basically no effect on the outflow of amoxicillin;the faster the flow rate,the AMX mobility The higher,mainly because the increase in flow rate leads to a shorter contact time between the pollutant solution and the BC in the sand column,resulting in a reduction in removal efficiency.?3?Effect of biochar filling on the dynamic removal of methylene blueThe outflow of quartz sand to MB is greatly affected by physical and chemical factors.As the p H increases,the outflow of MB gradually decreases,mainly due to the electrostatic effect between the sand column and MB;when the ionic strength increases When the MB outflow increases,it is mainly due to the repulsive force between the sand column and the MB;the increase in the flow rate will also cause the MB outflow to increase.When the sand column is filled with BC,the results of the MB outflow experiment show that the presence of BC in the sand column significantly hinders the outflow of MB.The more the BC is filled,the more obvious the blocking effect on the MB is.As the p H increases,the MB outflow gradually decreases;when the IS and flow rate increase,the MB outflow gradually increases;experiments show that the biochar in the sand column mainly affects the MB outflow through adsorption.