Technical-environmental assessment of CO2 conversion process to dimethyl carbonate/ethylene glycol

Utilization of CO2 to produce value-added chemicals is a promising approach to mitigate greenhouse gas emissions. In this work, a new process for the conversion of CO2 to dimethyl carbonate (DMC) and ethylene glycol (EG) was rigorously simulated and assessed in term of the technical performance and the environmental impact. The proposed model involves the conversion of CO2 catalyzed by ionic liquid-based catalysts, the reactive distillation with the reaction kinetics model, the pressure-swing distillation with rigorous phase equilibrium equations, and complex material-energy nexus between each unit. The results show that the carbon utilization efficiency of this process reaches 99% and the negative CO2 emission is 0.14 ton CO2/ton product achieving CO2 reduction. The green degree value of the entire process is 176.30 gd/h indicating that this new process can be evaluated as an environmental friendly process. Additionally, the retrofitted heat exchanger network designed via the pinch technique achieves 48.70% saving in heating utility consumption and increasing the green degree by 193.89 gd/h. (C) 2020 Elsevier Ltd. All rights reserved.

Automated summary

A new process for converting CO2 to dimethyl carbonate and ethylene glycol was proposed, showing high carbon utilization efficiency and environmental friendliness through rigorous simulation and assessment. The retrofit heat exchanger network designed via the pinch technique achieved significant energy savings and increased the green degree of the process.