Study on the Influence Mechanism of Furfural on Analysis of SARA Fractions

Elution chromatography was used to analyze the content of SARA fractions in simulated raffinate and extract phases containing furfural, and the influence mechanism of furfural on the content analysis of SARA in the two phases was explored by molecular simulation. The experimental results showed that the content analysis of SARA fractions was more affected by the furfural with a higher content of furfural in the sample. During the process of sample loading, some chromatographic bands of R and A significantly shifted down, some A being eluted down earlier while eluting S with n-heptane, and some R being eluted out earlier while eluting A with toluene. In addition, the molecular simulation results showed that the order of adsorption capacity of model molecules and FUL on the FCP-Al2O3 surface was S<A<FUL<R, and the order of interaction between S, A, R model molecules and FUL was S<A<R. The molecular simulation results revealed the mechanism of the influence of furfural on the analysis of SARA fractions, that was, the unadsorbed furfural would promote the desorption of some A and R, resulting in the downward movement of chromatographic bands and affecting the elution effect, thereby affecting the accuracy of the SARA fractions analysis data. Furthermore, the improved vacuum distillation method, namely the vacuum-oven method could be used to accurately determine the content of furfural in the sample.