Development of New Separation Analysis and Continuous Flow Analysis Using Supercritical Water or Subcritical Water

构建了以超临界水和亚临界水为流动相的色谱仪，并对其分离特性进行了研究，以阐明其潜力。分离特性的一个突出方面是柱效率。HETP随水流动相温度的升高而缓慢升高，这与从扩散率等物理性质所期望的结果不同。分离特性的另一个重要方面是各种溶质的保留行为。水流动相的溶剂强度随温度的升高而增大，甲醇与水的混合物（80/20）对应的水流动相为190℃。提出了一种描述和评价标准溶质保留选择性的新方法，即测定一组标准溶质相对于线性烷烃同系物的保留指数。考虑到烷烃在热水中难溶且对紫外检测器无反应的特点，本文以同类系列的乙酸烷基酯为基准，测定了各种溶质的保留指数。用单乙酸酯和双乙酸酯计算了前者的保留指数。参考气相色谱中麦克雷诺氏法等，选择了5种不同类型的标准溶质。反映保留选择性的保留向量以5个不同官能团为元素，确定为标准溶质与同形烃保留指数的差异。同样的官能团在过热水和同等溶剂强度的甲醇-水混合物中的贡献有所不同。保留选择性随水温的变化程度小于随甲醇-水混合物组成的变化程度。并对亚临界水连续流分析先进技术的基础研究进行了讨论。少

A chromatograph using supercritical water or subcritical water as mobile phase was constructed and its separation characteristics were investigated in order to elucidate its potentiality. One eminent aspect of the separation characteristics is the column efficiency. The HETP was increased slowly with the temperature of water mobile phase : a different behavior from that expected from the physical properties such as diffusivity. The other significant aspect of the separation characteristics is the retention behavior of various solutes. The solvent strength of water mobile phase was increased with the temperature and water mobile phase at 190 ℃ corresponded to the mixture of methanol and water (80/20). A new method describing and evaluating the retention selectivity was proposed, in which the retention indices of a set of standard solutes were measured relatively to linear alkane homologs. Taking into account the facts that alkanes are sparingly soluble in hot water and don't respond to … More UV detector, the homologous series of alkyl acetates were used as the reference for measurement of the retention index of any solutes. The retention indices of the former was determined by the calculation using a monoacetate and a diacetate. Five standard solutes of different types were chosen by reference to McReynolds' method in GC and so on. The retention vector reflecting the retention selectivity had the contributions of five different functional groups as element, which were determined as the difference in retention index between a standard solute and the homomorphic hydrocarbon. Some differences in the contribution of the same functional groups were observed between super-heated water and the mixture of methanol-water with comparable solvent strength. The extent of the variation in the retention selectivity with the water temperature was smaller than that with the composition of methanol-water mixture.Simultaneous determination by using plural reactors in series was also discussed for fundamental investigation of advanced techniques of continuous flow analysis using subcritical water. Less