First off, welcome to TFP!
A related question was put to me in a PM as follows:
iori8sun said:
... can you give me any advice in increasing the dissolution of BCDMH into Br solution? Likewise is there anything i can do to stabilize the solution for use as a liquid like sod. hypo.
I respond to that here as follows:
Normally BCDMH or DBDMH tablets/pucks are put in a floating feeder so you increase their rate of dissolving by opening up the feeder slots so that there is more water flow. They are also designed to work in hot water so the water should remain warm by keeping a cover on the tub when not in use.
If you just want to increase the bromine level, you simply shock with chlorine (such as unscented bleach) or with non-chlorine shock (MPS) assuming you have a sufficient bromide bank (if not, you can add sodium bromide). The BCDMH or DBDMH are only necessary if the bromide bank is low -- they are mostly a convenient way of adding bromine and chlorine (for BCDMH; for DBDMH this only adds bromine) since they are slow-dissolving tablets. See
this article in the Pool School for more info on bromine.
Additional comments:
I'm also not sure what is trying to be accomplished here. Is this for some experiment or for actual pool or spa use? From the first post it sounds like this will be for a pool, but why is bromine going to be used in a pool replacing sodium hypochlorite? You can't stabilize bromine to protect it from breakdown from sunlight -- it will last longer than chlorine in a pool with no CYA, but not as long as chlorine in a pool with CYA. I suppose that having CYA in a bromine pool might help shield lower depths from the UV in sunlight, but no one has tried that and it wouldn't protect water near the surface. CYA does not combine with bromine so the protection effect would certainly be far less than with chlorine.
Also, mixing ammonia with a bromine solution (from BCDMH) doesn't make bromine, but rather bromamine -- that is bromine combined with ammonia. Also, calcium chloride has nothing to do with production of bromine so I'm unclear as to why that is being considered.
It sounds like maybe you are trying to make a "concentrated bromine solution" analogous to chlorinating liquid. That's not how you normally add bromine to your pool. You could add sodium bromide to the pool and then add chlorinating liquid to activate it to bromine. Chlorine added to a pool with bromide in it will convert the bromide to bromine (and the chlorine gets converted to chloride). However, that doesn't eliminate the regular required addition of chlorinating liquid to the pool, if that's what you were trying to avoid (and I'm not sure why, since adding a bromine solution would be just as much effort). If you didn't want to have to regularly add a solution to the pool, then you would use BCDMH in a floating feeder if there is such a thing for pools (the water is colder so it dissolves more slowly). I don't understand why you want to use bromine in your pool -- perhaps you could start by answering that question.
Richard