In this study,the magnetic wakame biochar/Ni composites were prepared with three activating reagents of H_(3)PO_(4),ZnCl_(2) and KOH by one-step pyrolysis activation,characterized by BET,SEM,TEM,FI-IR,XRD,Raman,and el...In this study,the magnetic wakame biochar/Ni composites were prepared with three activating reagents of H_(3)PO_(4),ZnCl_(2) and KOH by one-step pyrolysis activation,characterized by BET,SEM,TEM,FI-IR,XRD,Raman,and elemental analyzer,and their adsorption performance for diesel were also analyzed.The results showed that wakame biochar/Ni composites had larger specific surface area,abundant porous structure,and various reactive groups,rendering its enhancement of adsorption efficiency.The adsorption experiments indicated that the maximum adsorption capacities for diesel using WBPA 0.5,WBHZ 0.5 and WBPH 0.5 were 4.11,8.83,and 13.47 g/g,respectively.The Langmuir model was more suitable for the adsorption isotherms process,and the Pseudo-second-order model could better describe the adsorption kinetic experimental.And the magnetic wakame biochar/Ni composites presented good stability and recyclability.This study provides a novel pattern for the high-value utilization of wakame,having huge potential in the treatment of oily wastewater.展开更多
In the era of serious greenhouse gas emission and energy shortage,it is necessary to use solid waste to prepare new renewable materials.In this work,the potential application of reed straw and electric furnace dust wa...In the era of serious greenhouse gas emission and energy shortage,it is necessary to use solid waste to prepare new renewable materials.In this work,the potential application of reed straw and electric furnace dust was explored.Firstly,magnetic carbon carrier(EFD&C)was prepared by high temperature calcination,and then magnetic carbon catalyst(SM@EFD&C)was prepared by activation of sodium methoxide.The catalyst was used to prepare biodiesel by transesterification reaction to test its activity and stability.Reed biochar,EFD&C and SM@EFD&C were detected by Diffraction of X-rays(XRD),Fourier transform infrared(FT-IR),Inductively coupled plasma(ICP),Scanning electron microscope(SEM),Transmission electron microscope(TEM),Brunauer-Emmett-Teller(BET),Vibrating sample magnetometer(VSM),Temperature programmed desorption of CO_(2)(CO_(2)-TPD)and Thermogravimetric analysis(TG-DTG).The results showed that SM@EFD&C catalyst had some characteristics including porous structure,easy adsorption and better magnetism.Under the reaction conditions of 65℃for 2 h with 6 wt%catalyst and methanol/oil molar ratio of 15:1,the biodiesel yields from reed biochar and EFD&C were only 4.88 wt%and 0.03 wt%,respectively,while the yield from SM@EFD&C catalyst reached 93.14 wt%(89.84 wt%after 7 cycles)under the same conditions,which proved that it had good catalytic activity and stability when used in biodiesel production.This study is of great significance of carbon dioxide emission reduction and environmental protection.展开更多
Analysis of pesticide residue levels in juice beverages is important to ensure safe consumption and avoid global trade concerns associated to pesticide contaminations.A simple,inexpensive and effective method was deve...Analysis of pesticide residue levels in juice beverages is important to ensure safe consumption and avoid global trade concerns associated to pesticide contaminations.A simple,inexpensive and effective method was developed for the determination of organochlorine pesticides(OCPs)in bottled juice drinks using GC-MS.Sample pretreatment was performed using dispersive solid-phase microextraction(D-μ-SPE)for matrix desorption and dispersive liquid-liquid microextraction(DLLME)for analyte enrichment.In this study,an affordable and effective sorbent for the adsorption of OCPs from juice samples was synthesized from avocado seeds mixed with magnetic precursors for D-μSPE.The ground avocado seeds combined with a magnetic precursor nanocomposite were characterized using various instruments including scanning electron microscopy(SEM),X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FTIR),and Brunauer-Emmett-Teller(BET)analysis.The solution obtained from D-μ-SPE desorption was used as a dispersant for the subsequent DLLME,which made the combination of D-μ-SPE with DLLME much easier.The effectiveness of the method was enhanced by optimizing the influential parameters in both D-μ-SPE and DLLME.Then after,the optimal values were determined for the real sample analysis.Accordingly,there was good linear dynamic range with a coefficient of determination(r2)≥0.9989.The limit of detection and quantification were 0.02–0.69 and 0.06–2.10 ng/L respectively.The method showed high enrichment factors ranging from 96 to 313 with recoveries of 87–100%.Intraday and interday precisions were≤4%.Compared with other reported methods,this method is a one-step,simple,cheap,fast,and environmentally friendly alternative and straightforward method for adsorbing organochlorine pesticides from sample solutions.These results demonstrates the high potential of the proposed method for the extraction and cleanup of contaminants in selected juices and other related samples.展开更多
With the gradually increasing protection awareness about electromagnetic pollution,the demand for absorbing materials with renewability and environmental friendliness has attracted widespread attention.In this work,co...With the gradually increasing protection awareness about electromagnetic pollution,the demand for absorbing materials with renewability and environmental friendliness has attracted widespread attention.In this work,composites consisting of straw-derived biochar combined with NiCo alloy were successfully fabricated through high-temperature carbonization and subsequent hydrothermal reaction.The electromagnetic parameters of the porous biocarbon/NiCo composites can be effectively modified by altering their NiCo content,and their improved absorbing performance can be attributed to the synergy effect of magnetic-dielectric characteristics.An exceptional reflection loss of-27.0 dB at 2.2 mm thickness and an effective absorption bandwidth of 4.4 GHz(11.7-16.1 GHz)were achieved.These results revealed that the porous biocarbon/NiCo composites could be used as a new generation absorbing material because of their low density,light weight,excellent conductivity,and strong absorption.展开更多
The magnetic iron oxide（Fe3O4） nanoparticles stabilized on the biochar were synthesized by fast pyrolysis of Fe（II）-loaded hydrophyte biomass under N2 conditions. The batch experiments showed that magnetic biochar...The magnetic iron oxide（Fe3O4） nanoparticles stabilized on the biochar were synthesized by fast pyrolysis of Fe（II）-loaded hydrophyte biomass under N2 conditions. The batch experiments showed that magnetic biochar presented a large removal capacity（54.35 mg/g）at pH 3.0 and 293 K. The reductive co-precipitation of U（VI） to U（IV） by magnetic biochar was demonstrated according to X-ray diffraction, X-ray photoelectron spectroscopy and X-ray absorption near edge structure analysis. According to extended X-ray absorption fine structure analysis, the occurrence of U-Fe and U-U shells indicated that high effective removal of uranium was primarily inner-sphere coordination and then reductive co-precipitation at low pH. These observations provided the further understanding of uranium removal by magnetic materials in environmental remediation.展开更多
基金This study was supported by the Fundamental Research Funds for Zhejiang Provincial Universities and Research Institutes(No.2021J004)the National Natural Science Foundation of China(U1809214)the Natural Science Foundation of Zhejiang Province(LY20E080014).
文摘In this study,the magnetic wakame biochar/Ni composites were prepared with three activating reagents of H_(3)PO_(4),ZnCl_(2) and KOH by one-step pyrolysis activation,characterized by BET,SEM,TEM,FI-IR,XRD,Raman,and elemental analyzer,and their adsorption performance for diesel were also analyzed.The results showed that wakame biochar/Ni composites had larger specific surface area,abundant porous structure,and various reactive groups,rendering its enhancement of adsorption efficiency.The adsorption experiments indicated that the maximum adsorption capacities for diesel using WBPA 0.5,WBHZ 0.5 and WBPH 0.5 were 4.11,8.83,and 13.47 g/g,respectively.The Langmuir model was more suitable for the adsorption isotherms process,and the Pseudo-second-order model could better describe the adsorption kinetic experimental.And the magnetic wakame biochar/Ni composites presented good stability and recyclability.This study provides a novel pattern for the high-value utilization of wakame,having huge potential in the treatment of oily wastewater.
基金the financial support from National Natural Science Foundation of China(Nos:52004095,51704119,and 21878161)the Natural Science Foundation of Hebei Province(E2017209243)Department of Education of Hebei Province(BJ2019038).
文摘In the era of serious greenhouse gas emission and energy shortage,it is necessary to use solid waste to prepare new renewable materials.In this work,the potential application of reed straw and electric furnace dust was explored.Firstly,magnetic carbon carrier(EFD&C)was prepared by high temperature calcination,and then magnetic carbon catalyst(SM@EFD&C)was prepared by activation of sodium methoxide.The catalyst was used to prepare biodiesel by transesterification reaction to test its activity and stability.Reed biochar,EFD&C and SM@EFD&C were detected by Diffraction of X-rays(XRD),Fourier transform infrared(FT-IR),Inductively coupled plasma(ICP),Scanning electron microscope(SEM),Transmission electron microscope(TEM),Brunauer-Emmett-Teller(BET),Vibrating sample magnetometer(VSM),Temperature programmed desorption of CO_(2)(CO_(2)-TPD)and Thermogravimetric analysis(TG-DTG).The results showed that SM@EFD&C catalyst had some characteristics including porous structure,easy adsorption and better magnetism.Under the reaction conditions of 65℃for 2 h with 6 wt%catalyst and methanol/oil molar ratio of 15:1,the biodiesel yields from reed biochar and EFD&C were only 4.88 wt%and 0.03 wt%,respectively,while the yield from SM@EFD&C catalyst reached 93.14 wt%(89.84 wt%after 7 cycles)under the same conditions,which proved that it had good catalytic activity and stability when used in biodiesel production.This study is of great significance of carbon dioxide emission reduction and environmental protection.
基金This work was financially supported by the College of Natural Sciences,Jimma University through the grand research project(CNS-Chem-11-2020/21-SP1).
文摘Analysis of pesticide residue levels in juice beverages is important to ensure safe consumption and avoid global trade concerns associated to pesticide contaminations.A simple,inexpensive and effective method was developed for the determination of organochlorine pesticides(OCPs)in bottled juice drinks using GC-MS.Sample pretreatment was performed using dispersive solid-phase microextraction(D-μ-SPE)for matrix desorption and dispersive liquid-liquid microextraction(DLLME)for analyte enrichment.In this study,an affordable and effective sorbent for the adsorption of OCPs from juice samples was synthesized from avocado seeds mixed with magnetic precursors for D-μSPE.The ground avocado seeds combined with a magnetic precursor nanocomposite were characterized using various instruments including scanning electron microscopy(SEM),X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FTIR),and Brunauer-Emmett-Teller(BET)analysis.The solution obtained from D-μ-SPE desorption was used as a dispersant for the subsequent DLLME,which made the combination of D-μ-SPE with DLLME much easier.The effectiveness of the method was enhanced by optimizing the influential parameters in both D-μ-SPE and DLLME.Then after,the optimal values were determined for the real sample analysis.Accordingly,there was good linear dynamic range with a coefficient of determination(r2)≥0.9989.The limit of detection and quantification were 0.02–0.69 and 0.06–2.10 ng/L respectively.The method showed high enrichment factors ranging from 96 to 313 with recoveries of 87–100%.Intraday and interday precisions were≤4%.Compared with other reported methods,this method is a one-step,simple,cheap,fast,and environmentally friendly alternative and straightforward method for adsorbing organochlorine pesticides from sample solutions.These results demonstrates the high potential of the proposed method for the extraction and cleanup of contaminants in selected juices and other related samples.
基金supported by the National Natural Science Foundation of China(No.U2004177)the Henan Province Science and Technology Research and Development Project in 2020,China(No.202300410491)the Key Scientific Research Projects of Provincial Universities in 2021,China(No.21A430045)。
文摘With the gradually increasing protection awareness about electromagnetic pollution,the demand for absorbing materials with renewability and environmental friendliness has attracted widespread attention.In this work,composites consisting of straw-derived biochar combined with NiCo alloy were successfully fabricated through high-temperature carbonization and subsequent hydrothermal reaction.The electromagnetic parameters of the porous biocarbon/NiCo composites can be effectively modified by altering their NiCo content,and their improved absorbing performance can be attributed to the synergy effect of magnetic-dielectric characteristics.An exceptional reflection loss of-27.0 dB at 2.2 mm thickness and an effective absorption bandwidth of 4.4 GHz(11.7-16.1 GHz)were achieved.These results revealed that the porous biocarbon/NiCo composites could be used as a new generation absorbing material because of their low density,light weight,excellent conductivity,and strong absorption.
基金supported by the National Natural Science Foundation of China (Nos. 21207092, 21577093)the Science and Technology Project of Shaoxing (No. 2014B70041)
文摘The magnetic iron oxide（Fe3O4） nanoparticles stabilized on the biochar were synthesized by fast pyrolysis of Fe（II）-loaded hydrophyte biomass under N2 conditions. The batch experiments showed that magnetic biochar presented a large removal capacity（54.35 mg/g）at pH 3.0 and 293 K. The reductive co-precipitation of U（VI） to U（IV） by magnetic biochar was demonstrated according to X-ray diffraction, X-ray photoelectron spectroscopy and X-ray absorption near edge structure analysis. According to extended X-ray absorption fine structure analysis, the occurrence of U-Fe and U-U shells indicated that high effective removal of uranium was primarily inner-sphere coordination and then reductive co-precipitation at low pH. These observations provided the further understanding of uranium removal by magnetic materials in environmental remediation.
