石墨商品归类化验的关键点分析

Analysis of Key Points of Laboratory Tests on Classification of Graphite Products

本文根据《中华人民共和国进出口税则(2023)》规定和石墨商品的特征,对石墨商品的归类进行归纳整理,采用X射线荧光光谱、X射线衍射和超景深显微分析的综合表征技术,建立了石墨商品归类化验方法。人造石墨的主要物相为石墨2H相,天然石墨及其加工产品的主要物相为石墨2H相和石墨3R相,可以通过X射线衍射法进行鉴别。天然石墨一般具有鳞片状结构特征,球化石墨具有椭球形结构特征,可以通过超景深显微分析进行鉴别。可膨胀石墨一般具有硫元素偏高、结晶度下降、表面出现褶皱等特征,需要综合判定。

The study combed the classification of graphite according to Import and Export Tariff of the People's Republic of China(2023) and the characteristics of graphite products.A comprehensive characterization technique of X-ray fluorescence spectroscopy,X-ray diffraction,and ultra-depth-of-field microscopy was used to establish a classification test method for graphite products.The main phase of artificial graphite is 2H phase,while the main phase of natural graphite and its processed products are 2H and 3R phases,which can be identified by X-ray diffraction.Natural graphite generally has squama texture,while spherical graphite has ellipsoidal texture,which can be identified through ultra-depth-of-field microscopic analysis.Expandable graphite generally has characteristics such as high sulfur content,decreased crystallinity,and wrinkles on the surface,which requires comprehensive judgment.