What are the main components of photographic waste liquid? How to extract silver?

Composition? Anyway, there is silver ~

The extraction of ~ ~ is generally carried out by filtration or electrolysis.

Filtration method: add a small amount of sodium sulfide (also known as alkali sulfide) to generate silver sulfide, filter out fixing solution with denim bag, and generate pure silver after burning.

Electrolysis: two carbon rods are inserted into the fixed solution, and both sides are electrified with direct current, 2-3v, and silver slowly precipitates from the negative electrode. This method is slow and incomplete, but relatively easy.