Differentiation of bitumen according to the refinery and ageing state based on FTIR spectroscopy and multivariate analysis methods

摘要

The aim of this work was to determine models for the characterisation of bitumen based on the Fourier transform infrared (FTIR) spectroscopy and a chemometrical evaluation of the spectra. For this, 90 bitumen samples were investigated using the attenuated total reflexion technology with multiple reflexions. The gained spectra were divided into two partial spectra with the relevant peaks and pre-processed with a Standard Normal Variate transformation and the first derivative. For a comprehensive evaluation, multivariate analysis methods in terms of the factor analysis and the discriminant analysis were used. Based on the pre-processed spectra and the evaluation methods, models could be determined allowing the differentiation of bitumen samples according to the refinery and the ageing state. Concerning the long-term aged states, a simultaneous consideration of samples from different refineries is possible while, for the differentiation of the unaged and the short-term aged states, the separate consideration of the different refineries is necessary. Thus, the FTIR spectroscopy as a fast investigation method enables the first characterisation of bitumen samples according to the refinery and the ageing state.