Sciencemadness Discussion Board

Calcium Chloride solution for ice control - how does it work - apply first or after icing?

RogueRose - 13-3-2017 at 13:10

Just saw a gallon solution of CaCl2 (no concentration listed) but it didn't feel too much heavier than a regular gallon of water so I would guess 10-20% solution. Anyway, I know it lowers the freezing point of water but I'm not sure how this is supposed to work. It says to apply to icy surfaces or apply prior to icy weather conditions. Is this supposed to coat the surface, dry/evap and leave a coating which keeps ice from forming? If sprayed on ice, wouldn't it just make it more slippery?

CaCl2 - 13-3-2017 at 22:11

I think it should melt ice if sprayed on it. If applied before freezing, it would easily be washed away.

RogueRose - 14-3-2017 at 02:14

Quote: Originally posted by CaCl2  
I think it should melt ice if sprayed on it. If applied before freezing, it would easily be washed away.


Hmmmm. Conflicting reports and suggestions from the retailer and packaging as well as you. I've heard the state uses this stuff to pre-treat the roads (in liquid form) and I have a buddy who plows snow for businesses and he has to keep the lots clear. He does the same thing, pretreat with the CaCl2 solution.

I say another one that was CaCl2 and Sodium Sulfate (or maybe bisulfate..) which made me curious as well. It was in an opaque jug so i couldn't tell if it was clear or not and unfortunately it didn't state proportions, just which there was more of.

XeonTheMGPony - 14-3-2017 at 12:02

Reason they use it is it coats the surface more efficiently, Secondly it only works to -20.

Most the salt trucks I had seen in bc used liquid salts, and CaCl is used due to its easy melting abilities.

macckone - 14-3-2017 at 20:20

Before works better. Lots of experience, bag in the garage.