A Continuous Diethanolamine Dehydrogenation Fixed Bed Catalyst and Reactor System.

Glyphosate is currently the largest volume commodity agricultural chemical. One key reaction step in the cost-efficient route for glyphosate synthesis is the dehydrogenation of diethanolamine (DEA) to form disodiumiminodiacetic acid (DSIDA). Early process technology reportedly utilized a Raney copper catalyst in a slurry reactor. To reduce processing costs, we sought to develop a continuous fixed bed process that would provide long catalyst lifetime, high DEA conversions, and high DSIDA selectivity, eliminating the operational costs associated with catalyst attrition, catalyst recovery, and catalyst recycle using slurry reactor technology, and increasing the operational efficiency relative to slurry-based batch processing. In this summary of our development program, we highlight key findings converting from a batch to a continuous oriented process while reviewing the scale-up methodology.