Study On Removal Of Tetracycline By Synthesis Of New Hypercrosslinked Polymer

Currently,an emerging pollutant,antibiotics,is threatening people's health with a rapid growth trend.This paper intends to apply the modified hyper-crosslinking polymers(HCPs)materials to study the removal of tetracycline in water by adsorption technology.HCPs is an excellent adsorbent material due to its unique porous morphology,stable chemical structure,large specific surface area,and simple synthesis method.In this paper,the building monomers and diplomatic agents for synthesizing HCPs were screened,and the synthesis path was optimized.Through the Friedel-Craft reaction,some economic monomers were synthesized into a series of HCPs with porous networks,aiming to prepare adsorbent materials that can efficiently and quickly remove antibiotic pollutants.The research findings are as follows:The carbazole was selected as the monomer source,and the Friedel-Craft reaction was carried out with 1,4-dichlorobenzyl as a diplomatic cross-linking agent to remove tetracycline in the aqueous solution.The structure of the synthesized product was analyzed by SEM,FTIR,and BET,verifying that a large number of pore-like structures existed on the surface of the product,with a specific surface area of 1013.5 m~2/g and an average pore diameter of 3.29 nm.The results of batch experiments revealed that when the solution was weakly acidic,it was favorable for the adsorption of tetracycline.The adsorption process conformed to the pseudo-second-order kinetic model and the Freundlich adsorption model,showing that the adsorption process was an irregular multi-layer surface adsorption.After five cycles of experiments,it could still maintain stable adsorption performance.A new synthetic route was developed to crosslink carbazole with"longer"diplomatic cross-linking agent,biphenyl dichlorobenzyl(BCMBP),aiming to establish an adsorbent with adjustable porosity.Through modern instruments,the structural analysis was conducted on adsorbents.Moreover,the batch adsorption experiments explored the effects of pH,the amount of adsorbent,the initial concentration of TC,and the temperature on the adsorption performance.The results showed that as the length of the cross-linking agent increased,the adsorption performance of TC increased by 87%,and the adsorption kinetics conformed to the pseudo-secondary model.Various adsorption isotherm models at different temperatures proved that The Freundlich isotherm was more suitable for this adsorption process.The results of placing coexisting ions and humic acid into simulated waste water revealed that both of them had inhibitory effects on TC removal.After five cycles of analysis,the removal rate still remained above 95%.In the above two sections,it was proved that HCPs have excellent adsorption capacity for TC.We continue to apply the nitrogen-rich monomer,2-aminobenzimidazole as a building unit to crosslink with diaminobenzimidazole to generate a new hyper-crosslinking polymer,HCP-AB20.SEM analysis showed that this was a spherical packing structure with a more dense appearance and a substantially uniform size.When p H=5.66,the adsorption capacity is 213 mg/g.The experiment obtained the adsorption kinetic model and isotherm of TC on HCP-AB20.Experiments show that changing the monomer type,the adsorption of TC still conforms to the pseudo second-order kinetic model and the Freundlich isotherm adsorption model.It is a multi-layer heterogeneous,spontaneous endothermic process with fast kinetics and efficient adsorption capacity.We adopt an external cross-linking agent method to synthesize HCPs series adsorbents in one step.The preparation process is mild,the operation is simple,the raw materials are economical,and the maximum utilization of resources is achieved.It provides reliable technical support for the actual treatment of antibiotic pollution in the future.