In this work a highly profitable process to produce biodiesel from castor oil is being reported, which is convenient in equatorial climate countries where the higuerilla bush grows everywhere. It is not necessary to preheat the reactants, nor to use heat exchange systems in the reaction. The temperature and catalyst concentration effects in the reaction yield and the kinetic constants quantifications are determined by proton nuclear magnetic resonance spectroscopy (H-1 NMR). The benefit of using H-1-NMR system for monitoring the results and outcomes of the transesterification reaction is clearly obtained. An irreversible step followed by a reversible stage, both of pseudo-second-order are obtained in the best modeling of experimental data, the rate constant and equilibrium constant obtained k(2) = 814.056 ml mol(-1) min(-1) and K = 17,190, respectively, are in agreement with previous experimental studies. A biocliesel demand of 3935 kg/month, requires to use two intermittent reactors producing two batches from 122.261/day. The first reactor must operate 14.42 min at 26 degrees C, stirring the reaction constantly at 700 rpm to produce this demand which improve its quality in the second reactor. The adequate molar ratio feeding of oil/methanol/sodium hydroxide is 1/6/0.20, respectively. (C) 2011 Elsevier B.V. All rights reserved.