There is a lot of information about de-icing products I didn’t cover in the lead post this month. Here are a few additional facts.
Sodium chloride (NaCl), while the most common de-icing salt, is not the only one. There are also magnesium chloride (MgCl2) and calcium chloride (CaCl2), both of which contain more chloride. Each of these products is effective to different surface temperatures. Sodium chloride is not effective at temperatures below 15-25⁰ F. Magnesium chloride is effective to about 0⁰ F; calcium chloride to about -25⁰ F.
Products such as beet juice and molasses do not melt ice. They merely bind to the salt pellets and make them sticky. That way the salt says on the road surface better when put down. This helps reduce the amount of salt that is needed to get the same de-icing effect. Beet juice is considered an anti-icing agent. Communities in some states are finding adaptive re-uses for products such as pickle brine which contains chloride. Since it is a brine solution though, it too uses less chloride to greater effect.
Some products make pet-safe claims because they are made mostly of urea ((NH2) 2CO). It is used mostly as an agricultural fertilizer. While true, that it doesn’t contain chloride, its high nitrogen concentration binds dissolved oxygen in water and releases nitrogen. This promotes and accelerates the growth of algae blooms which further uses up available oxygen to the detriment of beneficial and critically important aquatic organisms at the bottom of the food chain. It is also more expensive and not effective below 25⁰ F.
If you would like to learn more, here are some helpful resources.
Salt Smart Collaborative: www.SaltSmart.org
Wisconsin Salt Wise: www.wisaltwise.com