Technology

Reactions

The UOP Advanced MTO Process integrates the UOP/Hydro MTO process and the Total Petrochemicals/UOP Olefin Cracking Process (OCP) to provide an economical means to convert methanol to light olefins, primarily ethylene and propylene^[1]. 

• The UOP/HYDRO MTO process uses a fluidized reactor and regenerator system to convert methanol to olefins using a proprietary, SAPO-34 catalyst (Fig. 1).
• The Total Petrochemicals/UOP Olefin Cracking Process (OCP) converts the C₄⁺ byproduct stream from the UOP/HYDRO MTO process to ethylene and propylene.
• The effluent from the OCP reactor section is compressed and combined with the MTO products for final fractionation and purification.
  This further increases the overall yield from the integrated complex

Feedstock

Feedstock for the UOP Advanced MTO process is methanol (crude or high purity) usually produced from synthesis gas (CO + H₂), which is produced from cost advantaged feedstock sources such as coal, natural gas or petroleum coke^[1]. 

Catalyst

• The MTO reaction is catalyzed by the MTO-100 silicoaluminophosphate synthetic molecular sieve based catalyst. This catalyst has demonstrated the degree of attrition resistanceand stability required to handle multiple regenerations and fluidized bed conditions over the long term. The catalyst is highly selective toward the production of ethylene and propylene.
• The Olefin Cracking Process uses a proprietary zeolitic catalyst supplied by UOP. The catalyst provides high selectivity and yields with good stability and uniquely low coking tendency^[1].

Catalyst Regeneration

Similar to Fluid Catalytic Cracking (FCC), a portion of the catalyst is continuously withdrawn from the MTO reactor and transferred to the regenerator where accumulated coke is removed from the catalyst via combustion with air. A portion of the regenerated catalyst is continuously transferred from the regenerator to the reactor to maintain the proper inventory and activity of the catalyst in the reactor. This provides continuous smooth steady-state operation^[1]. 

Figure 1 - UOP Hydro MTO process flow sheet^[2].

Process Yields

The yields of the Advanced MTO Process as a comparative example in the patent application WO2018210827A1 are reported to be^[3]:

References

1. Honeywell UOP, Petrochemicals, Feb 2019, UOP Advanced Methanol to Olefins (MTO) Process Datasheet.
2. Advances in Catalysis for Methanol-to-Olefins Conversion - Scientific Figure on ResearchGate.
3. E. Borodina et al., WO2018210827A1, Application filed 15^th May 2015, MTO-OCP UPGRADING PROCESS TO MAXIMIZE THE SELECTIVITY TO PROPYLENE, Total Research & Technology.