煅后石油焦石墨化度计算的修正方法研究

STUDY ON OPTIMIZATION METHOD FOR CALCULATION OF GRAPHITIZATION DEGREE OF CALCINED PETROLEUM COKE

石油焦石墨化度的计算最常用的是Mering-Maire方法,其使用前提是炭素材料的(002)晶面间距d_(002)≤0.3440 nm。煅后石油焦尚未石墨化,因而d_(002)较大。若d_(002)>0.3440 nm,将无法采用该方法对煅后石油焦的石墨化度进行估算。针对该问题,提出由B值代替Mering-Maire式中d_(max)=0.3440 nm的思路,并以该方法计算得到3种d_(002)>0.3440 nm的煅后焦A,B,C的石墨化度分别为25.29%,24.58%,22.29%。该石油焦石墨化度计算修正方法与Mering-Maire方法能够较好地吻合。

The petroleum coke produced by the delayed coking process serves as a typical raw material for the production of artificial graphite anode of lithium batteries.The amount of lithium intercalated in the petroleum cokes is strongly related to the graphitization degree of petroleum cokes.The Mering-Maire method is commonly used to calculate the graphitization degree,which is based on the prerequisite that the interplanar distance of crystal face(d_(002))is lower than 0.3440 nm.The calcined petroleum coke does not undergo the graphitization process,so d_(002)is larger.If d_(002)>0.3440 nm,graphitization degree of calcined petroleum coke can not be estimated by this method.In this study,a B-value method was proposed based on three kinds of petroleum cokes A,B,C,whose d_(002)values are all greater than 0.3440 nm.The estimated graphitization degree for the petroleum cokes is 25.29%,24.58% and 22.29%,respectively.The modification method of graphitization degree proposed in this study is in good agreement with Mering-Maire method.