SIMULTANEOUS DETERMINATION OF 2-FURFURALDEHYDE, 5-HYDROXYMETHYLFURFURALDEHYDE AND MALONALDEHYDE IN MIXTURES BY DERIVATIVE SPECTROPHOTOMETRY AND PARTIAL LEAST-SQUARES ANALYSIS

2-Furfuraldehyde, 5-hydroxymethylfurfuraldehyde and malonaldehyde are known to react with 2-thiobarbituric acid when heated in an acidic medium. A study of the influence of several chemical and physico-chemical variables on the reaction was undertaken. The products of reaction show high absorption in the visible spectral region with several degrees of overlapping. The resolution of ternary mixtures of these compounds was accomplished by several chemometric approaches. A comparative study of the results obtained for simultaneous determinations in mixtures by using derivative spectrophotometry and partial least-squares analysis is presented. The multi-wavelength factor analysis-based method is demonstrated to be the method of choice for the multi-component analysis of ternary mixtures of these compounds.