Patent ID: 8198479

Claim:
A process for the oxidation of N-(phosphonomethyl)iminodiacetic acid or a salt thereof, the process comprising contacting said N-(phosphonomethyl)iminodiacetic acid or a salt thereof with an oxidant in the presence of a catalyst, wherein the catalyst comprises a carbon support having formed thereon a transition metal composition comprising a transition metal (M) and nitrogen, the transition metal being selected from the group consisting of copper, silver, vanadium, chromium, molybdenum, tungsten, manganese, cobalt, nickel, cerium, and combinations thereof, wherein the catalyst is characterized as generating ions corresponding to the formula MN x C y + when the catalyst is analyzed by Time-of-Flight Secondary Ion Mass Spectrometry (ToF SIMS) as described in Protocol A and the relative abundance of ions in which x is 1 is at least 20%.