3. Catalyst waste

Precious metal catalysts are used in industry and transport.

In industry, rhodium-plated platinum wire cloth (approx. 90% Pt, 10% Rh) is used for the gas-phase oxidation of ammonia in the manufacture of nitric acid. Still in fabric form, platinum is used to manufacture hydrocyanic acid, a basic product for plastics, and salts for galvanic deposits.

Catalysts for hydrocarbon hydrogenation reactions are platinoids deposited on a porous alumina support. Platinum accounts for 0.5 to 1% of the catalyst mass, while rhodium, in the Rh/Pt ratio = 0.3 to 0.5%, extends the catalyst's working life. Palladium catalysts are available for olefins and dehydrogenation. Other hydrogenation reactions using palladium dispersed in carbon (Pd-C) include the catalytic hydrogenation of carbonyl compounds to alcohols, aldehydes and ketones to alcohols, organosynthesis...