Gas-liquid chromatography, to determine

Heats of Transfer between Solvents. Kurkchi and logan (147) have used gas-liquid chromatography to determine specific retention volumes of acetylene (23), propyne (24), and 1-butyne (25) in eight solvents (isooctane, 9,18,25,26,28,41,52) at a number of temperatures, and thence have derived heats of solution, AHy, and of transfer between solvents, AHij. The later quantities (transfer from isooctane to HBA solvents) are well correlated by /8 and x ... 

Cruickshank A.J.B., Windsor M.L., Young C.L. (1966). The Use of Gas-Liquid Chromatography to Determine Activity Coefficients and Second Virial Coefficients of Mixtures. I. Theory and Verification of Method of Data Analysis, Proc. R. Soc. London, A, vol.295, n°1442, pp.259-270. ISSN 1471-2954... 

Takahashi [12, 13] used gas liquid chromatography to determine BHA and BHT in breakfast cereals. He obtained quantitative recoveries of 20 to 30 ppm of the antioxidants added to cereals. To determine antioxidants and preservatives in soya sauce and other foods, Takemura [14] converted these compounds to trimethylsilyl derivatives and analysed the product by GC. The sample was shaken with the silation reagent (1 ml) for 30 seconds, then set aside for 5 minutes and 2 pi of the solution was analysed by GC on, for example 20% of SE-31 silicone on Celite 545 at 200 °C with helium as carrier gas (22 ml/min) and hexane as internal standard. The method was applied to 15 preservatives and 7 antioxidants well-separated peaks were obtained for 4-hydroxy benzoate estars, phenol, xylenol derivatives and salicylic acid. The calibration graphs for methyl, ethyl, propyl and butyl-4-hydroxybenzoates were rectilinear for the range 0.5 to 4 mg. The method was used to determine 4-hydroxybenzoates in soya sauce. 

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