Application of chemometric techniques to the characterisation of impregnated materials obtained following supercritical fluid technology

The impregnation of salicylic acid following a supercritical fluid technolo gy was determined experimentally for various adsorbing matrices such as Flo risil, zeolite, silica gel and Amberlite under a wide range of experimental conditions. A thorough characterisation of these supercritical adsorption processes requires a large number of runs under various experimental condit ions in order to cover all possible sources of variance. which may result i ll a tedious and time-consuming task. The overall information contained in the data set generated in this series of experimental runs can be analysed more efficiently using chemometrics. Here. multivariate data consisting of adsorption values determined for each material were analysed with principal component analysis and partial least-squares regression (PLS). The corresp onding PLS models were subsequently applied to predict the impregnated amou nts for other experimental conditions. Results showed a reasonable concorda nce between the experimental and predicted values.