Ross W. Moshier

Feasibility of gas-liquid chromatography for quantitative determination of aluminiumIII, GalliumIII, IndiumIII and BerylliumII Trifluoracetylacetonates

Abstract The gas Chromatographic behaviour of the trifluoracetyl-aeetonates (TFAs) of aluminiumIII, galliumIII, indiumIII, berylliumII and thallium has been studied and conditions for their complete separation found. The thallium derivative has not been characterised, but produces a chromatographic peak well separated from the others. Elution products have been collected and examined for comparison with the injected material. An over-all relative mean error of 2%, based on calibration data, demonstrates the feasibility of gas chromatography with a thermal conductivity detector for the quantitative determination of aluminium, gallium, indium and beryllium. Using conditions established for complete separations, it is possible to obtain the gas chromatographic analysis of any combination of up to 5 metals by a maximum of two runs which involve a change in column temperature only. The TFAs of scandiumII, chromiumIII, copperII, manganeseIII, zirconiumIV, hafniumIV, zincII and thoriumIV are studied, enabling a prediction of interference in this method.

Determination of iron, copper and aluminium by gas-liquid chromatography.

Gas chromatography has been utilised in the analysis of two National Bureau of Standard alloys for quantitative determination of aluminium, iron and copper. In the analysis of N.B.S. 162a the relative mean errors were 3.13% for aluminium, 2.06% for iron and -1.72% for copper and for N.B.S. 164a the relative mean errors were -1.39%, -0.19% and -0.89% for aluminium, iron and copper, respectively. The procedure for analysis involves solution of the alloy, conversion of the metal ions to trifluoroacetylacetonates by solvent extraction and, finally, complete separation of the metal chelates and quantitative determination by gas chromatography using a column containing Gas Pack F coated with Tissuemat E, a polyethylene wax. Other metals present in the N.B.S. samples did not interfere with the determination of aluminium, iron and copper.