Chemical Research in Chinese Universities ›› 2009, Vol. 25 ›› Issue (6): 791-795.

• Articles • Previous Articles     Next Articles

Preparation and Characterization of Phosphorus Pentafluoride Gas for Lithium Ion Battery Electrolyte Salt

LIU Jian-wen*, LI Xin-hai, WANG Zhi-xing, GUO Hua-jun and HU Qi-yang   

  1. School of Metallurgical Science and Engineering, Central South University, Changsha 410083, P. R. China
  • Received:2008-10-28 Revised:2009-03-17 Online:2009-11-25 Published:2010-01-25
  • Contact: LIU Jian-wen. E-mail: changdeljw@163.com
  • Supported by:

    Supported by the National Basic Research Program of China(No.2007CB613607).

Abstract:

A novel preparation method of phosphorus pentafluoride(PF5) is introduced in details in the article. Phosphorus pentafluoride is mainly used to synthesize lithium ion battery electrolyte salt. In the experiment mesneproduct—hexafluorophosphoric acid(HPF6) was firstly prepared from phosphorus pentoxide(P2O5) and anhydrous hydrogen fluoride(HF), according to the chemical stoichiometrics, the optimum amount of excess HF used was about 60% and the optimum reaction time was 4 h; then HPF6 was dehydrated by oleum with an excess amount of 35%―40% which was heated for 40―50 min at 150 °C; thus HPF6 was decomposed to a mixture of gases containing PF5; impurity gases were removed through condensation in the presence of cooling water at 0 °C, then PF5 of high purity was eventually prepared. The production was characterized by infrared(IR) spectrometry and gas chromatography-mass spectroscopy-selected ion monitoring(GC-MS-SIM). Eventual results indicate that PF5 prepared by the novel method has a high target purity and a low amount of impurity and water.

Key words: Hexafluorophosphoric acid; Phosphorus pentafluoride; Preparation; Infrared spectrum; Gas chromatography-mass spectroscopy-selected ion monitoring