Research On Improving The Antioxidative Ability Of Porous Carbon

In the air, porous carbon can be easily oxidized under high temperature, limiting its abroad applications in catalytic fields. In this paper, in order to increase the antioxidative ability of porous carbon , boron in solid state was added to porous carbon which was preparated by KOH chemical activation. The condition of the experiments is under 800℃,at N2 atmosphere,the time of heat treatment is 2hor5h. In the experiments, by BET observing the changes of specific surface area and the aperture after the boron-doping of porous carbon,observing the boron-doping bringing the effects to the micropore.By TG/DTA observing the oxidative weight loss of porous carbon at different temperatures,observing the boron-doping bringing the effects to the antioxidative ability of porous carbon.By scanning electronic microscope observing the changes of exterior shapes,in order to find the antioxidative mechanism after the boron-doping of porous carbon.It has been proved that the antioxidative ability of porous carbon can be effectively increased by boron-doping because the quantity of active point of the surface of porous carbon and the rate of the surface's pore of porous carbon gradually were reduced after heat treatment, preventing oxidized gas diffusing from the surface to the interior of porous carbon, inhibiting the reaction between oxidized gas and porous carbon. And under better condition,the content of boron-doping is 10% in the porous carbon,the content of B4C is 25% in the boron-doping,the time of heat treatment is 5h.After boron-doping treatment, compared to raw material at 600℃the relative weight loss of porous carbon is decresing from about 70% to about 20%,satisfying the needs of the antioxidation at high temperature,although the surface area of porous carbon decreased 10%-20% , micro-reactive activation of porous cabon still reached 70.25.