预氧化法制备石油焦基活性炭的研究

 以石油焦为原料，采用先对原料进行预氧化处理，再进行水蒸气活化的方法制备活性炭。通过XRD、N2吸附、恒流充放电等测试研究了预氧化对所制备的活性炭的结构特性与电化学性能的影响，并开展原料结构与活性炭性能之间的相关性研究。结果表明，预氧化处理极大的促进了石油焦的活化反应，由此制得的活性炭比表面积达到299.7m2/g，比电容达到80F/g，均比未经预氧化的样品有显著提高。同时，石油焦原料结构对石油焦活性有较大影响，以细镶嵌型光学结构为主、晶化程度较低、挥发份含量高的石油焦具有较高的反应活性，制备的活性炭更易于形成发达的孔隙。

PREPARATION OF ACTIVATED CARBON FROM PETROLEUM COKE BY THE METHOD OF PRE-OXIDATION

Activated carbons were prepared from petroleum cokes by the method of pre-oxidation then steam activation.The structures of activated carbons were characterized by XRD and BET measurements.The electrochemical properties of activated carbons used as electrodes of supercapacitor were also investigated by constant current cycling method.It was found that the activity of activated carbons was extremely accelerated by pre-oxidation of air.The surface area and specific capacitance of activated carbons were 299.7 m2/g and 78 F/g,respectively,which were dramatically increased compared to the sample without oxidation by air before activation.Meanwhile,the activity of petroleum coke was greatly affected by the structure of petroleum coke.The petroleum coke with optical textures of small mosaics and small crystals is the most suitable material to form activated carbon.