I picked up a $30, smallish desiccant/tampon type filter for some testing applications. The filter is pretty well made! The pictures on many of these, just shows the 3/4" tampons. When I opened it up, I was surprised to find a mix of charcoal, and some little white beads. I needed an indicating type desiccant, so I replaced it with some indicating silica gel that I had on hand. I had just dumped the charcoal mix onto a little can, and had it sitting on my bench. After a few days, i was surprised to find the white beads liquified! My background in chemistry leads me to believe that the white beads were probably Calcium Chloride. The liquid would be pretty corrosive, and you probably couldn't regenerate the stuff. I would suggest that if you have, or get one of these, immediately replace the charcoal mix with silica gel, molecular sieves, or activated alumina.
