Energy Conversion and Management, Vol.138, 577-586, 2017
Intensification of monostearin (phase change material) synthesis in infrared radiated rotating reactor: Optimization and heterogeneous kinetics
The present article offers an intensification effort for the synthesis of glycerol monostearate (monostearin, a phase change material) using Amberlyst 36 (wet) catalyst. This work demonstrates the superiority of rotating batch reactor (RBR) over the stirred batch reactor (SBR) in glycerol (GL) - stearic acid (SA) esterification under far infrared radiation (FIRR). RBR depicted 92 +/- 1% monostearin yield, which is 40% higher than the yield obtained in SBR under optimal process condition viz., 20:1 GL:SA mole ratio, 363 K reaction temperature, and 6.0 wt.% catalyst concentration in only 25 mins. The speed regimes for mass transfer limitation and surface kinetics controlled were determined using Mears criterion. The heterogeneous surface reaction kinetics in RBR followed Langmuir Hinshelwood (LH)' mechanism (R-2 = 0.98) under resultant optimal condition. The reaction activation energy for the two different reactor configurations indicated that under identical operating conditions, SBR consumed almost double the energy required for RBR; thus representing superior energy-efficiency of RBR. Notably, the optimally synthesized monostearin demonstrated desirable properties of phase change material as confirmed by FTIR, TGA and DSC analyses. (C) 2017 Elsevier Ltd. All rights reserved.
Keywords:Monostearin synthesis;Phase change material;Heterogeneous reaction kinetics;Far infrared radiation;Rotating batch reactor;Energy-efficiency