On the current market, rock salt is a readily available ice melt option that is used by both property owners and municipalities to create traction control or eliminate ice on roads, driveways, and walkways.
However, the use of rock salt carries several significant drawbacks, the most serious being its impact on the environment. Excess salt can seep into ground water or leach into shallow soil on the side of roads.
Rock salt is hard on concrete, stone, and metals, often causing vehicles to rust or concrete to crack. This damage is attributed to the fact that rock salt is hydroscopic, meaning that it has a strong ionic attraction to water and absorbs it at a high rate. As ice and snow thaw, rock salts pull water into concrete pores. When temperature drops to the freezing point, water expands and places stress on concrete structures, leaving pits and cracks on the material.
Instead of pulling water into concrete pores, zeolite absorbs water and uses solar energy to embed itself into the ice and snow. Individual grains have large surface areas, multiple contact points, and ridged structures that do not deteriorate through the freeze and thaw process (Hogg, 2015).
A trial conducted at KMI Zeolite Inc. (Hogg, 2015) examined the durability of zeolite during hydration and dehydration, which are regular occurrences during the freeze and thaw cycle. The study was conducted outdoors during November 2014, a time when temperatures are continuously below freezing. Zeolite was placed on ice in a container and by means of solar absorption, it absorbed through the ice to the bottom of the container (Hogg. 2015). Then, the block of ice was turned over and zeolite once again absorbed through the ice. The process was repeated several times over the course of a month and the same results were observed. Study results demonstrate that zeolite can withstand freeze and thaw cycles indefinitely and degradation does not occur during the processes of hydration and dehydration (Hogg, 2015).
When zeolite is used as an additive and blended with other ice melt products (i.e. calcium chloride and sodium chloride) it can effective break down ice surfaces. Then, zeolite absorbs excess water, creating a high traction surface. In addition, zeolite absorbs many of the damaging chemicals contained in ice melt products and prevent them from contaminating nearby soil and water sources (KMI Zeolite Inc., 2013).