Homebrew PCBs

Getting back into this after many years absence, and am looking to etch my first simple PCB - the idea is to create the mask via a laser printer on inkjet photo paper, and then 'ironing' on the mask and etching with ferric chloride. My question is what do people do with the 'used' solution - I used to stick it back in the bottle and replace it when it took too long to etch a board, ie it was 'saturated'?

Is this a good approach or is it better to use (fresh) small amounts each time and dump it, in which case where?

In any event I would end up with a bottle of old etchant to get rid of, is there a safe/green approach?

Any comments/observations are welcome

Thanks

Chris