Macro Kinetics of N-Phosphonomethyliminodiacetic Acid Catalytic Oxidation

Abstract:

The oxidation of N-phosphonomethyliminodiacetic acid (PMIDA) to prepare glyphosate (PMG) over active carbon was investigated. Experiments were carried out with O₂ as the oxidizing agent in a 150-mL autoclave made in stainless steel, with reaction temperature ranging from 323.15 to 353.25K and the pressure from 0.12 to 0.40 MPa. The macro kinetic model of the reactions in series was developed, and the pre-exponential factor and activation energy were estimated from the measured data in experiments. The influence of dissolved oxygen concentration was also considered in this macro kinetic model. The results indicated that the two step reactions are all one-order to reactant (PMIDA or PMG) and 0.3 or 0.07 to O₂ respectively. The active energy was 12.98kJ/mol for the first step reaction and 10.87kJ/mol for the second step reaction.

• Periodical: Advanced Materials Research (Volumes 455-456)
• Pages: 872-879
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.455-456.872
• Online since: January 2012
• Authors: Yan Bao, Jia Wu, Xiao Ping Hu
• Keywords: Active Carbon (AC), Catalytic Oxidation, Glyphosate, Kinetic, N-Phosphonomethyliminodiacetic Acid

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