Reactive & Functional Polymers, Vol.28, No.1, 29-38, 1995
Extractive reactions with cationic exchange resins as catalysts (acetalization of aldehydes with alcohols)
The acid catalysed acetalization of aldehydes such as formaldehyde, acetaldehyde, glyoxal and glyoxylic acid, with alcohols are reversible reactions. In order to enhance the conversion of aldehydes, extractive reactions were carried out with the alcohols (e.g. 2-ethyl hexanol and n-butanol) having very low to low solubility in water. In such cases alcohols, in addition to being reactants act as extractive solvents for the acetals formed in the reaction. An experimental investigation was carried out using cation-exchange resins (Indion-130, Amberlyst-15 and Amberlite IR-120) as catalysts and significant conversion levels were realised for the reactions of formaldehyde and acetaldehyde; results were not encouraging for the extractive reactions of glyoxal and glyoxylic acid. The effect of different parameters, such as catalyst loading, temperature, mole ratio and aqueous phase concentration of aldehyde on the rate of reaction was studied.