- Various non-chloride-based deicers have been developed to prevent corrosion by chloride ions
- Further research, development is needed – inferior melting performance, expensive
- In foreign countries, it is mainly used for roads and exteriors in particular environments such as parking lots, bridges, and highways
1. Urea, CH4N2O
- Urea, also used as a fertilizer, absorbs 251 J/g of heat when melted
- Effective above –3.9 ℃(24.98°F)
- Safe for corrosion of steel and does not damage concrete but five times more expensive than salt
- When sprayed a lot, plants wither and yellow(weaker than potassium chloride)
- As microorganisms decompose it in water, it consumes oxygen
- Generates harmful ammonia that affects fish and other aquatic organisms
2. CMA(Calcium Magnesium Acetate)
- CMA is an alternative snow remover and deicer used for bridges and parking lots due to its environmentally friendliness and low corrosiveness
- According to a 1990 US Massachusetts Research study, the price is known to be 20 times more expensive than salt
- Effective above –6.7 ℃(19.94°F)
- In the case of 10% solution, the pH is 8 ~ 10, which causes alkalinity
- The CMA is the result of a study by Bjorksten Research Laboratories and is actively supported by the Federal
Highway Administration (FHWA)
- CMA shows a significant effect when sprayed before a snowstorm
- Salt mixed product is also commercially available
- Cons
1) CMA is slower to dissolve in snow or ice than salt and requires 1.2 to 2 times of spraying to have the same effect
2) CMA has a higher snow melting temperature
3) CMA is easy to produce acetic acid spontaneously through hydrolysis of acetic acid even if the pH is around 9, making it potentially harmful to the body
4) CMA has a lot of powder and may cause safety problems during spraying. CMA workers must wear dust masks.
5) CMA has a low density (35lb/ft bulk density), which tends to fly in haul trucks
- If the CMA(solid) remains on road, it will blow off the road after a few cars pass
6) CMA is susceptible to cake into dump trucks, shuttles, and spinners
7) CMA is hygroscopic, creating frost in previously sprayed areas
- During the day, dry areas remain wet, producing ice in the late afternoon or early morning.
3. Potassium Acetate, CH3CO2K
- Heat of dissolution is 151 J/g, in solid-state, developed as a substitute for glycol and urea
- Eutectic point is -60 ℃ in an aqueous solution of 49% concentration, effective above –20 ℃(-4°F)
Sodium Acetate
- Biodegradable into carbon dioxide and water in nature
- Lower biochemical oxygen demand (BOD) than glycol-based de-icer(commercially available in liquid form)
- Used as de-icer and prewetting agent
- Flexibility in spraying time since it can be used both after ice buildup and before pairing
- Expensive
4. Sodium Acetate, C2H3NaO2
- Compare to urea, sodium acetate works faster at lower temperatures, and less product is needed
Sodium Formate
- Like CMA, it causes a hydrolysis reaction to produce acetic acid
5. Sodium Formate, HCOONa
- Can use smaller amounts since Sodium Formate molecular weight is lower than acetate type
- The price of formic acid is similar to that of acetic acid
- Eutectic point is -17 ℃ in an aqueous solution with 30% concentration
- Due to its high density, it has less dust blowing problems compare to CMA
- Can spray in the form of a saturated or slurry solution
- No volatility or flammability