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Expanded graphite is a new type of nanoscale carbon materials , high temperature , corrosion resistance, electrical and thermal conductivity , excellent features , expanded graphite and other materials the composite can get high performance composite materials . The paper as raw material, using a combination of chemical oxidation microwave puffing Preparation of sulfur-free highly expanded graphite with perchloric acid and potassium permanganate , the experimental conditions were optimized by orthogonal test . Test method using SEM TEM XRD.XPS and IR characterization and the expanded graphite surface morphology and composition structure . The results show that : the optimal experimental conditions expanded graphite prepared for m1 ( natural flake graphite ) : m2 ( high acid ) : m3 ( potassium permanganate) = 1:4:0.5 , reaction temperature was 35 ° C , the reaction time was 40 min. Under this condition the expanding volume of the preparation of the expanded graphite of up to 760 mL / g. Seen by SEM and TEM observation : was vermicular expanded graphite apparent size of a few millimeters , by many graphite microchip internally developed network-like pore structure . XPS and R : analysis shows that the degree of crystallinity of the expanded graphite is not high, the layer spacing d = 1.48nm , expanded graphite surface containing only C the O two elements, the surface containing the C = O, CO, OC = O,-OH by XRD . and other polar groups . Homemade expanded graphite modified activated carbon / Teflon composite electrodes as the cathode , Ti/IrO2/RuO2 as the anode , Na2SO4 solution as the electrolyte , 4 - chlorophenol degradation effect in cotton diaphragm electrolysis system . The effects of the cathode chamber 4 - chlorophenol degradation effect of current density , electrolyte concentration , 4 - chlorophenol initial concentration , pH value , electrode spacing , and other factors . The results show that : 20% of the added amount of the carbon material of the expanded graphite , polytetrafluoroethylene and carbon material of the electrode with a ratio of 1:4 at a current density of 39 mA/cm2, the electrolyte concentration of 0.05 mol / L, and 4 - chloro phenol initial concentration of 100 mg / L, initial pH of 11 , electrode spacing of 4cm , expanded graphite composite modified electrode as the cathode cathode chamber 4 - chlorophenol degradation effect best electrolysis 120mmin 4 - chlorine phenol degradation rate of 98.7% .
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