scrapping an oxygen concentrator

I recently came across 2 oxycons and decided that they were too old and in need of desperate repair, so I decided to scrap them. My question is about the aluminum cylinders full of zeolite. Should I just dump them or is there some use? I've already removed everything including the motors and SMC valves, which I'll try to sell, but is there any other input from someone who has run across these?

Can you undo the cylinders and pour out the zeolite fragments? There must be a way for a technician to change the zeolite during a service. If not, ensure the cylinder is not pressurised then cut a hole in it to pour out the zeolite. The cylinders contains zeolite/nitrogen, so there's nothing flammable in them.

I saw another thread a little while ago where someone mentioned it having an O2 sensor with platinum. Unfortunately, I cannot find that post within a post now. Would one know where the sensor might be located on an oxycon? My guess is on the SMC valve (there was a little yellow cylinder coming off of it with an elec. connector and an inlet, I would take a pic, but it's friggin' cold out now!!!)