Determination of long-chained alkylimidazolium ionic liquids based on the hypochromic effect

摘要: The hypochromic effect of bromocresol green (BCG) resulted from long-chained imidazolium ionic liquids was investigated. may be caused by the formation neutral complex [Cnmim]2+[BCG]2−via electrostatic interaction and hydrophobic interaction. Based on spectral characteristics, a new method for determination is developed. proposed can performed using UV-vis spectrophotometer, at optimum λmin. Beer's law obeyed in concentration range 0.004–0.04 mmol L−1 [C14mim]Br [C16mim]Cl, detection limits are 0.0011 0.00095 respectively. Meanwhile, precision, accuracy tolerance also very good. fast, economical does not require organic solvents; it applied liquids.