Preparation And Multifunctional Application Of Furfural Residue-based Carbon Materials

Biomass waste can cause huge environmental harm if not handled properly,so people have tried various methods to turn these waste into treasure.Porous carbon materials prepared from biomass waste can be applied in many fields,such as CO2 solid adsorbents,organic pollutant adsorbents in water,and supercapacitor electrode materials.These applications not only enable biomass waste to realize their value,reduce the cost of producing porous carbon materials,but also bring new ideas to solve energy shortages and environmental crises.In this paper,furfural residue is used as a precursor,and the furfural residue-based carbon material FRKCs is prepared by a one-step carbonization activation method,which is used for CO2 solid adsorbent and supercapacitor electrode material.Urea was then used as a nitrogen source to prepare a furfural residue-based nitrogen-doped carbon material FRKC-N,which was used as a CO2 solid adsorbent,a dye adsorbent in water and a supercapacitor electrode material.The main work of this paper is as follows:(1)Using furfural residue as precursor,K2C03 as solid activator and CO2 as activating gas,furfural residue-based carbon material FRKCs was prepared by one-step carbonization activation method.Among them,the carbonized material FRKC-800 at 800? has the largest adsorption amount of CO2 under the conditions of 273K,298 K,and 318 K at 1 bar,which are 4.28,3.06,and 2.21 mmol/g,respectively.The maximum isosteric heat of CO2is 45.5 kJ/mol,and the adsorption selectivity for CO2/N2 adsorption is 25,23,and 20,respectively.The capacitance performance of the three-electrode system was tested in a 6 M KOH solution.At a current density of 0.1 A/g,the specific capacitance of FRKC-800 was 224.9 F/g.After 10,000 cycles,FRKC-800's capacitance retention rate is still as high as 93.5%.(2)FRKC-800 was nitrogen-doped with urea to prepare FRKC-N,a furfural residue nitrogen-doped carbon material.Under the conditions of 273K,298 K,and 318 K,1 bar,FRKC-N has a larger adsorption capacity for CO2,which is 4.77,3.36,and 2.50 mmol/g,respectively.The maximum isosteric heat of CO2 adsorption is 50.3 kJ/mol.At the same time,the sample FRKC-N has a CO2/N2 adsorption selectivity of 30,24,and 26.The capacitance performance of the three-electrode system was tested in a 6 M KOH solution.The specific capacitance of FRKC-N at a current density of 0.1 A/g is 284.8 F/g.After 10,000 cycles,FRKC-N's capacitance retention rate is still as high as 95.7%.In terms of dye adsorption,the maximum adsorption capacities of FRKC-N and FRKC-800 for MB were 616.4 mg/g and 573.5 mg/g,and the maximum removal rates were 99.7%and 99.1%,respectively.In addition,the adsorption capacities of FRKC-N for MO and RhB were 354.4 mg/g and 417.7 mg/g,respectively.The kinetic and isotherm fitting showed that its adsorption was consistent with the quasi-second-order kinetic model and Langmuir adsorption isotherm model.