Difference between diesel & non diesel cat. converters " ...The carrier material of a diesel particulate filter differs significantly from normal automotive catalytic converters for exhaust emissions (ACCs). Conventional automotive catalytic converters which have been instituted since the early 1990s consist of approx. 1kg of cordierite. This ceramic, made from aluminium, magnesium and silicon oxide, is easy to melt in electrical high-temperature furnaces. In this smelting process, the precious metals are separated from the ceramic and bound in what is called "collector metal". The smelting process is carried out under reducing conditions (release of oxygen), enabling a high yield in the recovery of precious metals.
In diesel particulate filters, the carrier material generally consists of approx. 3kg of silicon carbide (SiC). This material reacts very differently to the smelting process than cordierite. In this case, we use an oxidizing smelting process (addition of oxygen) to convert the carbon (carbide) into carbon dioxide and the silicon into silicon oxide. Only then it`s possible to efficiently recover the precious metal. If both material types, i.e. ACC and DPF, are mixed together, this makes the recovery of the precious metals extremely difficult or nearly impossible from a certain concentration onwards...
Catalytic converters – Hensel Recycling (hensel-recycling.com)
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