化学氧化法制备可膨胀石墨过程中的电位控制  

Optimization of initial redox potential in the preparation of expandable graphite by chemical oxidation

作　　者：陈雅萍[1] 李舒艳 罗瑞盈[1] 吕晓猛 王煊军 

机构地区：[1]北京航空航天大学物理科学与核能工程学院,北京100191 [2]西安高新技术研究所603室,陕西西安710025

出　　处：《新型炭材料》2013年第6期435-441,共7页New Carbon Materials

基　　金：国家自然科学基金(21071011)~~

摘　　要：以高锰酸钾、硫酸、天然鳞片石墨为原料，采用化学氧化法制备可膨胀石墨。通过调控体系初始氧化还原电位，并结合其膨胀容积值，探讨石墨氧化的最佳电位区间，采用扫描电镜及x射线衍射仪对样品进行表征。结果表明，当体系初始氧化还原电位为1340～1810mV时，能够获得平均膨胀容积大于230mL／g，最高300mL／g的可膨胀石墨，扫描电镜及x射线衍射结果证实了此区间的合理性。此法避免了传统化学氧化法通过复杂正交实验来确定最佳工艺的弊端，可为实现可膨胀石墨制备的自动化和工业化生产提供重要的理论依据。The initial redox potential is employed to control the quality of expandable graphite prepared from natural flake graphite by chemical oxidation using KMnO4 as oxidant and sulfuric acid as intercalation agent. The effects of the initial redox potential on the layer structure and the expansion volume of the expandable graphite are investigated by scanning electron microscopy and X-ray diffraction. Results show that there is an optimum initial redox potential range between 1340 and 1 819 mV, at which the extent of graphite layer oxidation is moderate and the intercalation reaction is complete. Low-order graphite intercalation compounds are formed and a high expansion volume of the expandable graphite can be obtained in this potential range. The redox potential can be used as a quality control parameter for the industrial preparation of expandable graphite.

关 键 词：可膨胀石墨 制备 氧化还原电位 

分 类 号：TQ127.11[化学工程—无机化工]