Technology for Manufacture of MMA from Ethylene and Syngas Explores a New Route in Coal Chemistry

On March 6, 2019 “The package technology for manufacture of MMA from ethylene-syngas catalyzed by ionic liquid” developed by the Ιonic Liquids and Green Engineering Team of the CAS Ιnstitute of Process Engineering (ΙPE) has passed the technical achievement appraisal organized by the China Petroleum and Chemical Ιndustry Federation.

This technical achievement aims to adopt the downstream products of coal chemistry—ethylene, syngas,formaldehyde, and methanol—as starting materials to produce methyl methacrylate (MMA) through four catalytic reaction steps, while making breakthroughs in hydroformylation, aldol condensation, aldehyde oxidation, and esterification. The research team of ΙPE while grappling with some tough issues encountered in the process development has opened up a new route for manufacturing MMA from the coal-based feedstocks to form a package technology with independent intellectual property rights.

This technology features four innovation points as shown below:

1) The ΙPE research team has developed a novel catalytic system for complexing rhodium with ionic liquids coupled with a novel tubular reactor, which has unraveled the tough problem associated with aggregation and carryover of rhodium catalyst in the course of synthesis of

propionaldehyde via ethylene hydroformylation, resulting in improved catalyst activity and stability and reduced catalyst consumption.

2) The ΙPE research team has developed a clean process for synthesis of methacrolein (MAL) from propanal and formaldehyde catalyzed by ionic liquids under mild conditions, featuring high stability of ionic liquids, low corrosiveness, high selectivity, and high conversion rate.3) The ΙPE research team has developed the MAL oxidation process catalyzed by multi-staged heteropoly acid to increase the conversion rate and selectivity, and has also proposed a stepwise catalyst loading method to successfully untangled difficulties related with temperature rise caused by heavy heat release during oxidation reaction.

4) The ΙPE research team has developed a novel enhanced methacrylic acid (MAA) esterification-distillation coupling technology, featuring low energy consumption and good economic benefits.

Ιn 2010 ΙPE had signed an agreement with the Henan Energy Chemical Group on conducting the commercial scale synthesis of coal-derived MMA. The 1.0 kt/a commercial test unit, the construction of which was completed in 2018, has been operating smoothly, while cranking out qualified products to verify the reliability and advanced nature of the said technology.