第五章 论文写作(五).ppt

第五章 论文写作（五） Temperature dependent solid-liquid extraction behavior of rare earths using N-butyl pyridinium hexafluorophosphate with benzoyl acetone Zhongwei Pan1,2,a, Zicheng Cai1,b, Mengjin Bian2,c, Ting Lian2,d, Zengyi Su1,e, Zhenzhen Zhang1,f and Duqing Huang1,g 1 School of Chemical and Biological Science, Quanzhou Normal University, Quanzhou, Fujian, 362000, P. R. China 2Qinghai Institute of Salt Lakes, Chinese Academy of Sciences, Xining, P.R. China azhongweipan@, b459304899@, cbianmengjin@163.com, d1372643993@, e578193013@, f719337051@, g464570300@. Keywords: Ionic liquid, Benzoyl acetone, Rare earths, Solid-liquid extraction. Abstract. Temperature dependent solid-liquid extraction (SLE) behavior of six rare earth elements (REs) was investigated using N-butyl pyridinium hexafluorophosphate ([BPy]PF6) as an ionic liquid solvent and benzoyl acetone (HA) as an extractant at 80 ℃. Parameters including the amount of [BPy]PF6, HA concentration, extraction time, extraction temperature and pH were investigated and optimized. The extracted species was neutral REA(n-1)Cl (n-1 = 3 or 2) in the REn+-[BPy]PF6-HA SLE system. The extraction percentage of REn+ could be 100% at stated pH and HA concentration. The recovery of REn+ extracted into [BPy]PF6 can be achieved using the mixture of 0.1 mol·L-1 ClCH2CO2H and 0.2 mol·L-1 HCl as stripping agents. REs were extracted into solid ionic liquid phase with smaller volume and concentrated to some extent. Furthermore the temperature dependent SLE allows to recover [BPy]PF6 after the extraction procedures. These results indicate that the proposed procedure can be used for the preconcentration and separation of REs using [BPy]PF6 with high melting point. Introduction Ionic liquids (ILs) are salts with a melting point close to or below room temperature. They form liquids composed of the majority of ions. ILs are generally considered as green solvents due to their high thermal stability, very low flammability and negligible vapo