异丙基膦酸单(1-已基-4-乙基)辛酯的某些基本常数的测定

Determination of Some Basic Constants of 1-Hexyl -4 -ethyloctyl Isopropylphosphonic Acid

用两相滴定法测定异丙基膦酸单（１－己基－４－乙基）辛酯（ＰＴ－２，ＨＬ）在水中的溶解度Ｓ，在水中的解离常数Ｋ在水－正庚烷中的分配常数Ｋｄ及二聚常数Ｋ２，利用ＳＯＬＷＲ计算程序，简单快速地处理两相滴定数据，得到结果为：Ｓ＝３．６８ × １０－５ｍｏｌ／Ｌ，ｐＫａ＝５．４９，ｌｏｇ Ｋ２＝４． ６７，ＩｏｇＫｄ＝ ２． ６７（２５±０． ５℃）．

Some basic constants of l-hexyl-4-ethyloctyl isopropylphosphonic acid (PT-2) such as solubilities (s), dissociation constants (Ka) in water, dimerization constants (K2) in heptane solvent and distribution constants (Kd) between water and n-heptane were determined by a potentiometric two-phase titration. The results are as follows:s = 3. 68 × 10-5 mol/L, PKa= 5. 49, logK2 = 4. 67 and logKd = 2. 67 (25 ±0. 5℃ ). An excellent program SOLVER in Microsoft Excel was employed to calculate the values of logK2 and logKd.