(83a) Simulation and Experimental Investigation for Biodiesel Production Using Reactive Distillation

Abstract

     The present work concerned with studying the behavior of reactive distillation to produce biodiesel (methyl oleate) by the reaction of methanol and oleic acid using homogeneous catalysts H₂SO₄, experimentally and theoretically.

     Experimentally, after checking the experimental conditions of biodiesel production using bench experiment, a lab-scale packed reactive distillation column was constructed which consist of a heat resistance glass distillation column 42 cm packing height and 3.5 cm inside column diameter, packed with glass raschig rings of 10 mm length, 6 mm outside diameter, and 3 mm inside diameter at atmospheric pressure.

    The effect of many variables on conversion of oleic acid to biodeisel have been studied such as molar ratio of methanol to oleic acid 4:1, 6:1 and 8:1, amount of catalyst 0.6, 1.2 and 1.8 g sulfuric acid/g oleic acid, reaction time 36, 57 and 75 minutes, and reaction temperature 100^oC, 120^oC and 130^oC. The design of experiments by the Taguchi method was considered for performing the minimum numbers of experiments of 9. the best operating conditions obtained when the reaction takes place in the still are MEOH/OLAC feed molar ratio 8:1, catalyst amount 1.2 g sulfuric acid/g oleic acid, time of reaction 57 min and reaction temperature 130^oC, with 93.5485% conversion of oleic acid. The Molar ratio (OLAC/MEOH) was the most influential parameter on the conversion of oleic acid, while the time has less effect by compare to other variables.

   The properties of biodiesel (methyl oleate) such as viscosity, flash point, density and carbon residue were measured experimentally and compared with ASTM standard for biodiesel and petrol diesel. The comparison gives that methyl oleate ester could be used as alternative diesel.

   Theoretically, an equilibrium model (EQ) was simulated using MATLAB (R2010a) to solve MESHR equations. UNIQUAC liquid phase activity coefficient model is the most appropriate model to describe the non ideality of OLAC-MEOH-MEOL-H₂O system. The results of the developed model were compared with the results of experimental work which give a good agreement according to their linear correlation coefficient r and multiple coefficient of determination R² with percentage error of 2.5%.