I often use Sodium Hydroxide as a desiccant, When should it be changed?
Is it still 'active' once it has liquefied completely or should it be changed at that point? I try and change it once it is all slush but lately
drying plant material it can be slush in an hour or so.
So i am wondering if once it has turned into liquid does it still pull water from the air?
I am keeping the liquid with intentions of drying it out in air and using the carbonate formed for non critical stuff.
I got the Hydroxide pretty cheap as prills in a 25Kg sack, i keep then in a large metal sealed drum. Four months later they still seem in good shape.RogueRose - 13-7-2016 at 02:42
I'm not sure how much is turned to carbonate but either way, it if is even 50/50, it could be heated, cooled, broken up with a sledge hammer or
something - then reused. It will absorb water as slush an to some point as a liquid - determining when that point is where it stops should be
determined by initial weight of the NaOH and the weight as a liquid. Bubbling air through it as a liquid might be worth a try.
IDK how much plant material you are drying, grams, kilo's or 10's kg's. I would highly advise against NaOH as the initial desiccant. I would try
putting the plant material in a box and pipe air through it (heated air is better) using a blower of some kind or a vacuum output. I think you will
be amazed at how quickly water is lost this way. Heck you could probably use a shop vac, put the plant material inside and turn it on (extending the
intake pipe to the bottom would help a lot). If you have garden hose (black is best), you could rig up the hose to feed the input and put the hose on
black pavement. If you have multiple hoses, put them in parallel as the resistance will be less but heat transfer should be the same. NEMO-Chemistry - 13-7-2016 at 05:27
Thanks, normally i dry upto around 1Kg max at a time, but some types contain alot of water.
I might try sodium chloride as a desiccant as well.RogueRose - 13-7-2016 at 12:23
