Construction Of Novel Three-Dimensional Carbon-Based Material For The Separation And Enrichment Of Trace Organic Pollutants

With the sustainable development of society,environmental and food safety issues have become more and more prominent.The analysis and detection of trace organic compounds in food and the environment has become a current research focus.Hence,it is imperative to develop fast,efficient,simple,and eco-friendly sample pretreatment techniques.In this paper,four novel three-dimensional porous carbon-based adsorption materials were designed and prepared by simple room temperature stirring/solvothermal method with in situ carbonization based on the premise of morphology regulation and composition doping,includeing octahedron carbon cages,hollow raspberry-liked magnetic carbon material,magnetic hierarchical carbon framework composite material,and multifunctional flower-liked magnetic carbon materials.The ingenious design of the adsorbent materials'morphology can not only increase the specific surface area and expose more adsorption sites,thereby increasing the adsorption capacity of the material to the target,but also facilitate mass transfer path,increase the area of effective contact materials,and makes the target fast contact with adsorption sites,so as to improve the adsorption ability of materials.Therefore,it can achieve efficient pre-enrichment of trace-level targets.In addition,the magnetic properties of materials can be assigned through rational doping components,which facilitates the simplification of the operating process.The four carbon-based materials as solid phase extracting materials are applied to highly efficient the separation and enrichment of trace organic pollutants?fluoroquinolones anti-inflammatory drug?FQs?,pyrethroids insecticide,phthalate esters plasticizer?PAEs?and sulfonamides antibacterial?SAs??in real samples,and combined with high performance liquid chromatography?HPLC?to realize the high sensitive detection of trace organic pollutants:?1?A unique three-dimensional?3D?porous Cu@graphitic octahedron carbon cages?Cu@GCC?as solid phase extracting materials were constructed by rapid room-temperature synthesis of a Cu-based metal-organic framework?MOF?with further pyrolysis in N₂.Its ability to separate and pre-enrichment four FQs?enrofloxacin,ciprofloxacin,norfloxacin,lomefloxacin?was investigated.Various factors influencing extraction efficiency were studied in detail to determine the optimal extraction conditions,such as adsorbent dosage,adsorption time,pH and ionic strength of solution,eluent type,eluent volume,eluent time and solution volume.The interaction between the adsorbent and the target was explored,mainly?-?interaction and H-bonds interaction.Applied Cu@GCC as adsorbent,a dispersive solid phase extraction?d-SPE?method combined with HPLC-UV was developed for detecting four FQs in environmental and food samples.This method was applied to the determination of FQs in chicken muscle,fish tissue,seawater and river water samples with the recoveries between 81.3 and 104.3%,and relative standard deviations?RSDs?<5.2%?n=5?.This method has been successfully used to the determination of FQs in real samples and satisfactory experimental results have been obtained.?2?A three-dimensional magnetic hollow porous raspberry-like hierarchical Co/Ni@carbon microspheres?3D Co/Ni@C?were synthesized by using a bimetal-organic framework?Co/Ni-MOF?as a precursor and subsequent calcination under nitrogen.Its ability to separate and pre-enrichment two pyrethroids?ethofenprox,bifenthrin?was investigated.Various factors influencing extraction efficiency were studied in detail to determine the optimal extraction conditions,such as adsorbent dosage,adsorption time,pH value and ionic strength of solution,eluent type,eluent volume,eluent time,solution volume and methanol proportion in solution.The 3D Co/Ni@C exhibits excellent extraction ability and separation efficiency for target analytes,which is ascribed to the beneficial effects of facile analyte transport?due to the presence of free pores?,the abundant number of adsorption sites?which warrant efficient extraction?.In addition,the material's outstanding structural stability and satisfactory magnetic properties endow it an excellent recycling ability.The interaction between the adsorbent and the target was explored,mainly?-?interaction and hydrophobic interaction.Applied3D Co/Ni@C as adsorbent,a dispersive magnetic solid phase extraction?d-MSPE?method combined with HPLC-UV?detection wavelength:220 nm?was developed for detecting two pyrethroids in real samples.The established detection method for two pyrethroid pesticides in food and environmental samples has a high enrichment factor?937-1012?and satisfactory recoveries?85.6-106.9%,RSDs<5.9%?n=5??.?3?A 3D magnetic porous N-Co@carbon dodecahedron/hierarchical carbon framework?3D N-Co@C/HCF?hybrid has been successfully synthesized by integration of the ZIF-67 into HCF and then calcination under an inert gas?N₂?.The ability of 3D N-Co@C/HCF to separate and pre-enrichment five PAEs?dimethyl phthalate,diethyl phthalate,dibutyl phthalate,butyl benzyl phthalate,dicyclohexyl phthalate?was explored.A series of experimental parameters,such as the amount of adsorbent,adsorption time,pH of the solution,eluent type,eluent volume,eluent time,and solution volume were systematically studied to determine the optimal extraction conditions.The interaction between the adsorbent and the target was investigated,and the adsorption mechanism was revealed,mainly?-?interaction and hydrophobic interaction.3D N-Co@C/HCF as magnetic sorbent show good extraction ability for PAEs,which is attributed not only to the abundant adsorption sites?due to the presence of large specific surface area?and the extremely strong?-conjugated system of 3D N-Co@C/HCF,but also to sufficient contact spaces and facile transport channels?ascribe to the interconnected hierarchical3D porous structure?between targets and the material.Moreover,3D N-Co@C/HCF shows good good reusability due to its excellent magnetic and structural stability.Applied 3D N-Co@C/HCF as adsorbent,a d-MSPE method combined with HPLC-UV was developed for detecting five PAEs in environmental and beverage samples.This method revealed a high enrichment factor?230-281?and satisfactory recoveries?87.1-107.2%?with the RSDs?n=5?less than 5.7%for the determination of PAEs in real samples.?4?The excessive accumulation of sulfonamides?SAs?drugs make it imperative to develop novel materials for boosting simultaneously efcient removal and precise monitoring of multiple SAs.Herein,3D hollow flower-like Ni@nitrogen-doped graphitic carbon?3DHFNi@NGC?was fabricated via a facile one-pot hydrothermal route and subsequent pyrolysis.The resultant 3DHFNi@NGC exhibits a unique 3D hollow hierarchical architecture assembled by a layer-by-layer interlacing of corrugated nanosheets subunits,thereby affording numerous interconnected channels,available internal/external surfaces as well as suitable interior cavities.The removal ability and the separation and enrichment ability?trace level?of five SAs?sulfadiazine,sulfamethazine,sulfamerazine,sulfamethoxypyridazine and sulfamethoxazole?were investigated.Through the study of adsorption kinetics and adsorption isotherms,3DHFNi@NGC exhibited a high total saturated adsorption capacity and fast adsorption rate for SAs.The removal ability of the material was evaluated by using spiked river water and municipal sewage and 3DHFNi@NGC shows strong anti-interference ability and practical application feasibility.The adsorption mechanism between the adsorbent and the target has also been investigated,mainly?-?interaction,H-bond interaction and hydrophobic interaction.In addition,various factors affecting the extraction efficiency,such as the effects of the amount of adsorbent,adsorption time,ionic strength,eluent type,eluent volume,elution time and solution volume,were studied to determine the optimal extraction conditions.Applied 3DHFNi@NGC as adsorbent,a d-MSPE method combined with HPLC-UV was developed for detecting five SAs in environmental samples.This method shows high enrichment factors?252<EFs<291?,wide linear range(0.2-100 ng mL^-1)and low detection limits(0.035-0.071 ng mL^-1).These indicate that the smart 3DHFNi@NGC could be a promising candidate for the synchronous remediation and sensitive detection of multiple SAs in aqueous systems,presenting a viable option for sewage treatment and water quality monitoring.