Valenta J N, Weber S G
PPG Industries, Pittsburgh, PA 15101, USA.
J Chromatogr A. 1996 Jan 26;722(1-2):47-57. doi: 10.1016/0021-9673(95)00689-3.
Environmental concern is renewing interest in selective, waste-free extractions. A recent report demonstrated an improved extraction of phenobarbital by means of a specifically designed molecular receptor. In that work, the solvent was CHCl3. The current work is the first step in extending extractions based on molecular recognition to reusable solvents, namely plasticizers. Phenobarbital aqueous/organic partition coefficients, receptor solubility, and phenobarbital-receptor-formation constants in several plasticizers and in their CHCl3 solutions are reported. In addition, by a thermodynamic cycle, the free energy for transfer of the barbiturate-receptor complex from CHCl3 to plasticizers has been calculated. Finally, the data have been displayed in coordinate systems representing extraction efficiency and selectivity. The most selective extraction medium yielding useful extraction efficiency is dioctyl phthalate.
对环境问题的关注正在重新激发人们对选择性、无废萃取的兴趣。最近的一份报告表明，通过一种专门设计的分子受体可以改进苯巴比妥的萃取。在该项研究中，使用的溶剂是三氯甲烷。目前的工作是将基于分子识别的萃取扩展到可重复使用的溶剂，即增塑剂的第一步。本文报道了苯巴比妥在几种增塑剂及其三氯甲烷溶液中的水/有机分配系数、受体溶解度以及苯巴比妥-受体形成常数。此外，通过一个热力学循环，计算了巴比妥酸酯-受体复合物从三氯甲烷转移到增塑剂的自由能。最后，这些数据已在表示萃取效率和选择性的坐标系中显示。产生有用萃取效率的最具选择性的萃取介质是邻苯二甲酸二辛酯。
