放电等离子体石墨提纯方法与机制研究

Graphite, as a industrial raw material, dominates a very important position in certain industries, such as photovoltaic solar, atomic energy & nuclear energy, automotive industry and space technology, etc.. These industries require high purity graphite with 99.9% carbon content or even higher. Thus research and development of high purity graphite materials has become the development tendency for the carbon industry, which is one of the most urgent-addressed problems for advancing wider and deeper development of graphite materials. But the available physical and chemical methods have the technical defects of high purification cost, high hydrochloric acid corrosion of equipments and environment, prolonged technological process. Thus how to develop an more advanced technique of producing high purify graphite has become a research hotspot in recent years at home and abroad. This research project aims to apply the synchronization technique of arc discharge plasma purification and graphitization, which can refine raw graphite ore and improve the graphite purity to 99.9% and even higher. Compared with thermotechnical method and acid-alkali method, this processing craft has the technological merits of simple equipments, stabilization, reliability, less initial investment, less energy consumption, less production cost, simple craft and environmentally friendly. This technique can provide theoretical and technical support for developing high added-value graphite industry.

石墨材料作为一种工业原料，在一些特殊行业尤其是高科技领域具有举足轻重的地位，如光伏太阳能、核能原子能、汽车工业、航天技术等，但是其碳含量需要在 99.9%甚至99.99%以上。一般石墨产品的纯度无法满足高纯石墨行业的要求，因而，高纯石墨材料的研发已成为目前炭素行业的发展趋势，也是石墨材料向更宽、更深领域发展亟需解决的问题之一。现有技术的物理法和化学法，提纯成本高、酸碱对设备和环境腐蚀严重、工艺流程时间长，因此开发出一种生产高纯石墨材料的优良工艺，已经成为近年来国内外研究的热点。本项目拟利用放电等离子纯化和石墨化同步工艺，采用电弧等离子体，利用快速产生高温特性协同注入化学活性物，除去石墨中的杂质，纯度达到99.9%及以上，与热工法和酸碱法相比，具有设备简单、稳定、可靠性高、前期投资小、能耗小、成本低、工艺简单、环境友好等特点，为石墨高附加价值工业化应用提供理论和技术支持。

石墨作为一种工业原料，在众多行业尤其是高科技领域具有举足轻重的地位，特别是高纯石墨，已经成为炭素行业的发展趋势。本项目针对现有石墨提纯技术中成本高、酸碱对设备和环境腐蚀严重、工艺流程时间长等问题，探索利用放电等离子体纯化和石墨化同步工艺，拟采用电弧等离子体的快速产生高温特性，协同注入化学活性物，去除石墨中的杂质。本项目采用黑龙江省鸡西市的大鳞片石墨作为提纯样品，建立了大气压氩气环境下直流电弧等离子体石墨提纯实验原理样机，研究了大气压氩气电弧等离子体炬的特性，确立了大气压氩气环境下直流电弧等离子体炬提纯大鳞片石墨的最佳条件为送粉速率10g/min、电流400 A、气流速25 Nl/min时石墨纯度达到极值为99.21%。该方法效率较高，比氢氟酸法、氯化锫烧法等环境污染、设备腐蚀低，在提高提纯效率的同时，对环境友好并保证了石墨的品质。