Cat Converter Honeycomb

How to recover a large percentage of the precious metals washcoat from your cats, block off one end fill it with water then freeze it, as the ice expands inside the monolith it scrubs off most of the precious metals.

As the ice melts save the water and any fine powdered residue into a small pail once the ice has completely melted tap gently on the sides of the cat then pour a pint of fresh clean water through the cat to remove any clingers.

The majority of the heavies will settle to the bottom of your pail, but there will be some float, I use coffee filters to catch the powder on average I've been getting 1.5 grams.

Wear gloves when handling catalytic monoliths and or any byproducts you've created.

With your saved precious metals powders you can now by-pass the cat buyer and sell directly to any refinery that specialises in precious metals.

Below a small chunk of monolith encased in ice, second image showing how much catalyst was removed. No dangerous chemicals.