“scientist’s calculations reveal that the procurement costs of the source materials and the energy cost of the entire extraction process are 50 times lower than the value of the gold that can be recovered. “
If we assume that “source materials” cover the circuit boards, whey, acids and any other chemicals, then byproduct processing and waste disposal hasn’t been addressed in any way. What’s the processing plant supposed to do anything that isn’t gold, silver or copper?
Anyway, this technique could work in tandem with a normal circuit board leaching plant. If you already have a factory for processing this sort of feed material, you could try to reduce the cost of operating one of the steps by using whey sponge instead.