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The adsorption of some hydroxy-acids (i.e. citric, tartaric and salicylic ) on a γ-alumina support has been investigated by transmission FT-IR. The results imply that the observed changes in the IR spectroscopic properties of the supported hydroxy-acids are mainly due to interaction of the acids with alumina hydroxyl groups. The IR spectra in the C=O stretching region of the hydroxy-acids supported on alumina are quite different from those of the unsupported compounds.

The infrared and Raman spectra of the three crystalline modifications of hydroquinone (HQ), known as α-HQ, β-HQ and γ-HQ, have been measured and compared with the spectra of HQ solutions. The spectra have been assigned on the basis of a normal coordinate analysis of the molecule and a factor group analysis of the crystals. The hydrogen bonds are relatively the strongest in β-HQ, the weakest in γ-HQ.

The adsorption of EDTA on a modified γ-alumina support has been investigated by transmission FT-IR. The results allow the conclusion that acidic and alkaline procedures used for γ-Al2O3 modification have an insignificant influence on the EDTA adsorption.