We read the above-mentioned article by Dragomir and Jobson (2005) with interest. The authors present a new synthesis and design methodology for reactive distillation columns that feature both reactive and nonreactive sections. The proposed methodology is based on graphical techniques and uses the concept of stage composition lines in the transformed composition space. This methodology was applied to the syntheses of methyl tert-butyl ether (MTBE) and diethyl carbonate (DEC). The proposed methodology appears to be thorough and sound. However, we will show subsequently that a probably incorrect thermodynamic data-set was applied in the case of DEC synthesis. Consequently, incorrect results were obtained. Furthermore, we believe that the authors made a very questionable assumption in the calculation of the residue curve map in the transformed composition space in the case of the DEC synthesis, and thus, we will present a residue curve map that does not rely on that assumption. (C) 2012 Elsevier Ltd. All rights reserved.