I don’t see anything about the cost of this method.
If it cannot produce more value than it costs, it is useless.
It's probably heavily dependent upon scaling. Doesn't sound like it's there yet. But at the current price of gold, I'd bet he'll have takers.
This is the key take away.
““It’s estimated that a ton of e-waste contains at least 10 times more gold than a ton of the ore from which gold is extracted.”l
Having worked in Guyana on a gold mine I can assure you getting gold from Ewaste is more environmentally friendly than hydraulic mining. You first strip mine off all the jungle above the deposits, then using high pressure water hoses you turn to liquid all the underlying strata with the runoff going into sluces where the dense material is separated from the lighter clays and muds. You then use acids to leech the microscopic gold particles out of the remaining materials. All the runoff goes directly into the local watershed untreated I might add. Gold is $2600+ TOZ today if they got 99.9% out of ewaste they are making money for sure as its gold content is an order of magnitude higher than ore you can use chemicals in the $100+ per litre range and laugh all the way to the bank. MOF are cheap they are industrial chemicals used in tonne quantities for such things as catalysts for hydrocarbons cracking they are valued in dollars per metric tonnes not dollars per ounce.
Every ounce recovered from waste means hundreds of tonnes of earth under pristine jungle doesn’t get washed into a River system in the third world and that’s a good thing. I was there for a university friend of mine his father owns the mine and I am a geochemistry expert his son is a hydrologist you need both to hydromine.