Supported Catalysts, Not Elsewhere Specified

Classification depends on which metal functions as the primary active substance. If the precious metal (palladium) is the catalytically active component and the base metal is a promoter or support modifier, heading 381512 likely applies. If the base metal (molybdenum) is the active substance and the precious metal is incidental, 381519 may be appropriate. Technical data sheets and supplier declarations identifying the active catalytic component are essential, and a CBP binding ruling is advisable for ambiguous formulations.

Spent catalysts containing certain metals — particularly those with residual hazardous constituents — may be subject to EPA Resource Conservation and Recovery Act (RCRA) regulations if classified as hazardous waste. Importation of hazardous waste for disposal is generally prohibited under US law, though imports for reclamation or regeneration may be permitted under specific conditions. Importers should assess the material's regulatory status before shipment.