Evaluation of a rotary valve/cold trap/reinjection system for capillary columns

Abstract

SummaryThis paper describes a cold trapireinjection system for capillary columns which utilizes a flow switching rotary valve. Sample enrichment is performed in a liquid nitrogen-cooled glass trap attached to the valve. Evaporation of enriched compounds is carried out with the aid of an electric heating coil. Parameters such as cryogenic trapping efficiency, reinjection rates, transference of sample, and adsorption, as well as overall performance, are examined. In addition, a comparison is made between the cold trapireinjection techniqueand injection witha gas-tight syringe.

A Joule‐Thomson cooler for stationary‐phase or thermal focusing in capillary GLC

“…Thus, dithizone has been utilized to separate Cu (II), Ni (II), Co (II), Pb (II), and Hg (11). In the same research work, On the other hand, dithiocarbamate complexes of several metal ions have been separated by in situformation,i.e., formation ofthe complexes within the chromatographic system when the chelatingagent is present in the mobile phase [4].Thissamemethod has been utilized in the case of ternary complex formation by pyrrolidinecarbodithioate and morpholinecarbodithioate with several metal ions [5]. In the above cases, the chelating agent was not included in the mobile phase and the previously formed chelates were introduced into the chromatographic column.…”