1. Sodium Chloride, NaCl
– Low price, universally used
- Endothermic reaction requires heat when dissolved in water (83J/g)
- Effective above –9.4 ~ -6.7℃(15.08 ~20.48°F)(effective temperature within 15-20 minutes after spraying)
- Below –12.2℃(10.04°F), less effective(cannot melt the snow)
- The components, sodium ions (Na +) and chloride ions (Cl-), are both harmful to plants because they
interfere with nutrient absorption and growth
- Salt mist may even damage plants away from the road
- Salt accumulates in the soil and contaminates the roots, dehydrates the earth, and causes the plants' yellowing, shrinkage of leaves, and drying at the end of branches
- Salt extraction can be performed by spraying water, but the dense structure with high clay content is a problem because water does not drain well
- Caution during the late winter or early spring seasons should be taken when using this deicer, especially when the ground is not frozen
2. Calcium Chloride, CaCl2
- Price is higher than salt and price fluctuates (216 USD in Korean procurement standards, up from
155 to 302 USD per ton depending on the season)
- Initial melting speed is very fast due to the dissolution reaction involves high calorific value
- Effective de-icing up to –32 ℃(-25.6°F)
- Much less damage to plants than sodium chloride, but plants wither and yellow when used
- Short storage period, must store in a moisture-proof bag
3. Magnesium Chloride, MgCl2
- As with calcium chloride, the dissolution reaction is exothermic; however, it has a lower calorific value
- Effective at above –15 ℃(5°F)
- Magnesium chloride solution causes extensive damage
- Magnesium ions react with calcium hydroxide to form magnesium hydroxide,
- Oxychloride (Mg (OH)Cl・4HO) is produced in the presence of chlorine ion
- Calcium silicate hydrate (CSH) is also replaced with MSH (magnesium silicate hydrate); MSH deteriorates concrete because CSH forms it without cementitious properties
4. Potassium Chloride, KCl
- Can also be used as a fertilizer; it absorbs heat when dissolved in water and is five times more expensive than Sodium Chloride. (It is often mixed with salt.)
- Effective above –4 ℃(24.8°F)
- No damage on concrete, but spraying a lot will cause plants to wither and cause yellowing of the leaves
5. Chloride Based Eco-friendly De-icer
5.1. Solid Form Chloride Base Eco-friendly De-icer
- Chloride Base + Corrosion Inhibitor is added
1) To minimize corrosion and reduce the overuse of corrosion inhibitor, magnesium chloride is often replaced with calcium chloride since magnesium chloride is less corrosive
→ Inferior Melting Performance(Frictional force improvement (secondary de-icing effect) according to de-icing in the field is 1/3 of conventional de-icer)
2) Damage aquatic ecosystems due to the use of large amounts of corrosion inhibitors (inferior to Acetate)
3) Insufficient corrosion inhibit rate despite the over usage of corrosion inhibitor
: Compared to sodium chloride, 20 ~ 30%
4) Competitors using corrosion inhibitors at about 6% and it greatly increases the price
: Anodic Inhibitor is used as a corrosion inhibitor and is very costly
5.2. Liquid Form Chloride Base Eco-friendly De-icer
- Most eco-friendly liquid de-icer manufacturers use calcium chloride or potassium chloride + corrosion inhibitor
- Fast initial melting performance using calcium chloride
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