Determination of trimethylsilyl derivatives of silicate anions by gas chromatography using a hydrogen flame- ionization detector

Abstract

Eight trimethylsilyl (TMS) derivatives were used as standard substances in studies of the determination of TMS derivatives of silicate anions. The internal standard method was used for the determination of TMS derivatives with a gas chromatograph equipped with a hydrogen flame-ionization detector and n-tetradecane as internal standard. TMS derivatives and n-tetradecane wre dissolved with chloroform. The relative peak intensifies of the eight TMS derivatives on the gas chromatogram were a linear function of their molar concentration and of silicon concentration.It was found that a linear relationship exists between the relative peak intensifies and the atomic composition of the TMS molecules (C/Si) at equivalent concentrations with respect to silicon. By using this linear relationship and linear calibration graphs for TMS derivatives with respect to silicon concentration, a method for the determination of TMS derivatives of low-moleculr-weight silicic acids was established.