Abstract
This study developed a method to fabricate a surface-oxidized rigid carbon foam(ORCF)with hierarchi-cal macro-nanoporous structure via KOH activation of the carbon foam with two kinds of macropores followed by HNO3 hydrothermal oxidation.The structures of the prepared ORCF were characterized us-ing scanning electron microscopy,transmission electron microscopy,X-ray diffraction,Fourier transform infrared(FTIR)spectra,X-ray photoelectron spectroscopy,and N2 adsorption-desorption analyzer.Results demonstrate that the ORCF possesses a fluffy and porous structure with rich oxygen-containing groups.There are numerous through-holes on its pore surfaces connected with two-level macropores forming hi-erarchical macroporous channels.Meanwhile,the ORCF remains a good bulk structure with a compression strength of 0.74 MPa at a bulk density of 0.09 g cm-3.Batch adsorption experiments for malachite green(MG)and Pb2+were studied through the single variable method to investigate the effects of different ini-tial conditions on its adsorption process.The ORCF has maximum adsorption capacities for MG and Pb2+of 587.68 mg g-1 and 157.80 mg g-1 with high partition coefficients of 17.41 mg g-1 μM-1 and 14.86 mg g-1 μM-1,respectively.The experimental data are suitable for Langmuir isotherm and Pseudo-second-order kinetic models,which correspond to monolayer chemisorption.Thermodynamic analysis indicates that the adsorption process is spontaneous and endothermic.Moreover,the removal percentages of MG and Pb2+by the ORCF could remain above 90％after five cycles,implying that the ORCF is an efficient adsorbent with good adsorption ability and cycling stability.
基金项目
National Natural Science Foun-dation of China(51872049)
NETL
NSTL
维普
万方数据