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The synthesis of 1,1-dibutoxyethane or acetaldehyde dibutylacetal was studied in a batch reactor by reacting butanol and acetaldehyde in a liquid phase, using Amberlyst-15 as the catalyst. The reaction equilibrium constant was experimentally determined in the temperature range 20-40°C at 6 atm, where K a ) 0.00959 exp[1755.3/T (K)]. The standard properties of the reaction at 298.15 K were estimated: ∆H°) -14.59 kJ mol -1 , ∆G°) -3.07 kJ mol -1 , and ∆S°) -38.64 J mol -1 K -1 . Kinetic experiments were performed in the temperature range 10-50°C at 6 atm. A two-parameter kinetic law based on a Langmuir-Hinshelwood rate expression, using activity coefficients from the UNIFAC method, was used. The kinetic parameters are k c ) 2.39 × 10 9 exp[-6200.9/T (K)] (mol g cat -1 min -1 ) and k s,D ) 2.25 × 10 -4 exp[3303.1/T (K)]. The activation energy of the reaction is 51.55 kJ mol -1 . This work is an important step for further implementation of an integrated reaction-separation process, such as a simulated moving-bed reactor.

The present work intends to investigate how mobile phase composition influences the adsorption behavior of ketoprofen enantiomers (a nonsteroidal anti-inflammatory drug) on an amylose-based chiral stationary phase (Chiralpak AD). Three mobile phase compositions were studied: the usual 20% ethanol/80% n-hexane mixture and two pure mobile phases; methanol and ethanol. Pulse and breakthrough experiments under preparative conditions were carried out in order to measure and test adsorption isotherms. The results obtained show that, for preparative separations, pure ethanol is a better mobile phase than the usual 20% ethanol/80% n-hexane mixture: it allows higher solubility of the racemate, lower retention times, and also a higher selectivity at high enantiomer concentrations. These are aspects of crucial importance when the final goal is to achieve high productivity preparative separations, as it is shown for the simulated moving bed (SMB) operation.

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