A continuous diethanolamine dehydrogenation fixed bed catalyst and reactor system

• A Cu/Co/ZrO2 catalyst enables continuous production of disodiumiminodiacetic acid.
• Yields of 98% are achievable in a series of adiabatic trickle beds.
• Laboratory tests should be conducted under commercially representative conditions.

We have developed a fixed bed Cu/Co/ZrO2 catalyst and reactor system for the production of disodiumiminodiacetic acid by dehydrogenation of diethanolamine. This process can give high molar yields (>98%) in a series of adiabatic reactors with interstage heating. This research and development program proceeded in three stages: catalyst discovery, reactor design, and process development. The discovery of a catalyst formulation that is superior in activity and selectivity to sponge-metal copper enabled project success. Subsequent reactor scale-up proceeded based on laboratory scale measurements of the reaction kinetics and catalyst lifetime. Validation experiments demonstrated the importance of using feed compositions and operating conditions in the laboratory that are identical to those expected in the full-scale operation.