Sustainable Glycerol Carbonate Manufacturing: Process, Synthesis, Design, and Control

Abstract

A proposed economic steady-state process design is developed for valorizing glycerol, a coproduct of biodiesel manufacturing, to glycerol carbonate (GC) via transesterification with dimethyl carbonate (DMC). Methanol is a coproduct of the reaction. The process flowsheet is synthesized using residue curve maps and consists of a pressurized reactive distillation (RD) column followed by three low-pressure simple distillation columns. The sensitivity of the MeOH−DMC azeotrope to pressure is exploited to recover pure MeOH coproduct and recycle the unreacted DMC. Comparison with recently published RD− pervaporation and RD−extractive distillation process designs shows their cost objective to be, respectively, 47 and 20% higher than that of the proposed design. The energy consumption per kmol GC product is also higher by 12 and 26%, respectively. Rigorous dynamic simulations show that the developed process design has good controllability, with a traditional decentralized plant-wide control system effectively handling the principal disturbances with tight product quality control.