Technology

Process Description

In the standard thermal glycol reaction process, ethylene oxide (EO) and water are reacted at an elevated temperature (about 200°C) and pressure without catalyst. This process typically yields about 90–92% monoethylene glycol (MEG) and 8–10% heavier glycol products, mainly diethylene glycol (DEG) and triethylene glycol (TEG). The proportion of the higher glycols is limited by using excess water to minimise the reaction between the EO and glycols^[1].

The resultant water–glycol mixture from the reactor is then fed to multiple evaporators where the excess water is recovered and largely recycled^[1].

Finally, the water-free glycol mixture is separated by distillation into MEG and the higher glycols^[1].

Process Licensing

Shell offers two versions of the MASTER process, each optimised around a family of industry-leading catalysts. MASTERHS is optimised around the latest High Selectivity (HS) Shell catalysts, while MASTERHP offers a lower capex solution and operates at higher work rates by leveraging the exceptional stability of Shell’s High Performance (HP) catalysts^[2].

Shell has issued licenses for 89 EO/EG plants worldwide, 53 of which are still operating^[2].

References

1. Shell Catalysts & Technologies, 22^nd Mar 2021, ENHANCEMENTS IN ETHYLENE OXIDE/ETHYLENE GLYCOL MANUFACTURING TECHNOLOGY WHITE PAPER.
2. Shell, MASTER (EO/EG) Process (accessed 29th Apr 2024).