化学学报 ›› 2011, Vol. 69 ›› Issue (11): 1280-1286. 上一篇    下一篇

研究论文

1-甲基-3-乙基咪唑缬氨酸盐离子液体[C2mim][Val]的热化学

关伟1,2,王彩霞1,2,王珍1,陈三平*,1,高胜利*,1   

  1. (P1P天然与合成功能分子教育部重点实验室 西北大学化学与材料科学学院 西安 710069)
    (P2P辽宁大学化学院 沈阳 110036)
  • 投稿日期:2010-11-09 修回日期:2010-12-30 发布日期:2011-01-27
  • 通讯作者: 高胜利 E-mail:gaoshli@nwu.edu.cn
  • 基金资助:

    氨基酸离子液体的热力学性质研究

Thermochemistry on 1-Methyl-3-ethylimidazolium Valine Ionic Liquid [C2mim][Val]

Guan Wei1,2,Wang Caixia1,2, Wang Zhen1, Chen Sanping*,1, Gao Shengli*,1   

  1. (1 Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xi an 710069)
    (2 College of Chemistry, Liaoning University, Shenyang 110036)
  • Received:2010-11-09 Revised:2010-12-30 Published:2011-01-27
  • Contact: Shengli Gao E-mail:gaoshli@nwu.edu.cn

用中和法合成了氨基酸离子液体1-甲基-3-乙基咪唑缬氨酸盐([CB2Bmim][Val]). 在298.15±0.01 K下, 利用恒温溶解反应热量计测定了不同含水量的[CB2Bmim][Val]溶解成不同质量摩尔浓度溶液的溶解焓, ΔBsolBHBmB (w), 借助标准加入法(SAM)和Archer方法得到了无水离子液体[CB2Bmim][Val]的标准摩尔溶解焓, . 利用RB-II型精密转动弹热量计测定了该离子液体的燃烧热, 计算了其标准摩尔燃烧焓 和标准摩尔生成焓 |并结合该离子液体的标准摩尔溶解焓和乙基咪唑阳离子[CB2Bmim]在水溶液中的标准摩尔生成焓, 计算了[Val]P离子在水溶液中的标准摩尔生成焓. 利用RD496-III型热导式微量热量计测定了不同质量摩尔浓度[CB2Bmim][Val]水溶液的稀释焓, 根据扩展的Debye-Hückel方程计算得到的相对表观摩尔焓PφPL和根据Pitzer离子相互作用模型的计算值在实验误差范围内很好一致.

关键词: 缬氨酸, 离子液体, 溶解焓, 燃烧焓, 稀释焓

An amino acid ionic liquid, [C2mim][Val] (1-ethyl-3-methylimidazolium α-aminoisovaleric acid salt), was prepared by the neutralization method. Using the solution-reaction isoperibol calorimeter, the molar solution enthalpies of ionic liquid [C2mim][Val], ?solHm(w), with known initial mass fractions of water, w2, and with different molalities were determined at 298.15 ±0.01 K. In terms of standard addition method (SAM) and Archer’s method, the standard molar enthalpy of solution for [C2mim][Val] without water, ΔsolHmθ, was obtained. The combustion energy of the ionic liquid was determined using an RB-II type the rotating-bomb combustion calorimeter. The standard molar enthalpy of combustion, ΔcHmθ, and the standard molar enthalpy of formation, ΔfHmθ, were calculated. In terms of standard molar enthalpy of solution, ΔsHmθ, and the standard molar enthalpy of formation for cation of [C2mim]+, the standard molar enthalpy of formation for anion of [Val]? in water solution were calculated. Using an RD496-III heat conduction microcalorimeter, the molar enthalpies of dilution, ΔDHm(mi→mf), of aqueous [C2mim][Val] with various molalities were measured. The values of apparent relative molar enthalpy, φL, were calculated using extended Debye-Hückel equation, which are in good agreement with that calculated using Pitzer’s ion-interaction model.

Key words: valine, ionic liquid, enthalpy of solution, enthalpy of combustion, enthalpy of dilution