The synthesis of acetaldehyde dimethylacetal was studied in a batch reactor by the acetaldehyde and methanol reaction in the liquid phase, using the acid resin Amberlyst-15 as the catalyst. Acetal synthesis was also performed with Y-type zeolite in order to compare the results for both catalysts. The reaction equilibrium constant was determined experimentally in the temperature range 293.15-333.15 K at 1.0 MPa: K eq ) 0.014 3 exp[2 142.5/T(K)]. The standard molar reaction properties were obtained at 298.15 K: ∆S°) -35.34 J mol -1 K -1 , ∆H°) -17.81 kJ mol -1 , and ∆G°) -7.28 kJ mol -1 . Kinetic experiments were carried out in the temperature range 293.15-313.15 K at 0.6 MPa. A two-parameter model based on a Langmnir-Hinshelwood rate expression was considered, using activity coefficients from the UNIFAC method, which can describe the experimental kinetic results. The kinetic law is 2 , and the parameters are k C ) 6.91 × 10 13 exp[-8 702.6/T(K)] mol g -1 min -1 and K D ) 2.37 × 10 32 exp[-22 713/T(K)]. The activation energy of reaction for the synthesis of acetal is 72.35 kJ mol -1 . The relationship between the effectiveness factor and the Thiele modulus was determined.

The synthesis of dimethylacetal (1,1-dimethoxyethane) was performed in a Simulated Moving Bed Reactor (SMBR) pilot unit LICOSEP 12-26 (Novasep, France) with 12 columns packed with the acid resin Amberlyst-15 wet (Rohm & Haas, France). For the operating conditions used, the performance parameters obtained were as follows:  acetal purity, 91.41%; productivity rate, 5.17 kgacetal/(Ladsorbent day); and desorbent consumption, 7.11 Lmethanol/kgacetal. The effect of the switching time, feed composition, and desorbent flow rate in the performance of the SMBR was studied by means of two mathematical models approaches:  the SMBR model (for the concentration profiles and performance parameters) and the True Moving Bed Reactor (TMBR) model (for the reaction separation regions).

The synthesis of dimethoxyethane using acetaldehyde and methanol as raw-material on a fixed bed adsorptive reactor packed with Amberlyst-15 resin was studied. Dynamic binary adsorption experiments were carried out in the absence of reaction at 293 K in a laboratory scale column. The parameters of the Langmuir type multicomponent adsorption isotherms were determined, by minimizing the difference between the experimental and calculated stoichiometric times of breakthrough curves. The mathematical model used to describe the adsorptive reactor dynamic behavior includes axial dispersion, mass transfer resistances, reaction kinetics, and multicomponent Langmuir adsorption isotherms. The mass transport phenomena through the external film and micropores were not taken into account explicitly; however, they were lumped in the global mass transfer coefficient. The model predicts the experimental results obtained for the reaction and regeneration experiments well, in terms of the outlet molar concentration of the species history.

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