Dichlorofluoroethane
[CAS# 1717-00-6]

Identification

• Classification: Organic raw materials >> Organic fluorine compound >> Fluoroethane series
• Name: Dichlorofluoroethane
• Synonyms: 1,1-Dichloro-1-fluoroethane; Freon 141b
• Molecular Formula: C₂H₃Cl₂F
• Molecular Weight: 116.95
• CAS Registry Number: 1717-00-6
• EC Number: 404-080-1
• SMILES: CC(F)(Cl)Cl

Properties

• Density: 1.3±0.1 g/cm³, Calc.^*, 1.25 g/mL
• Melting point: -104 °C
• Index of Refraction: 1.387, Calc.^*
• Boiling Point: 35.5±8.0 °C (760 mmHg), Calc.^*, 32 °C
• Flash Point: -33.4±11.9 °C, Calc.^*

^* Calculated using Advanced Chemistry Development (ACD/Labs) Software.

Safety Data

• Hazard Symbols: GHS07 Warning
• Risk Statements: H412-H420
• Safety Statements: P273-P501-P502

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Chronic hazardous to the aquatic environment	Aquatic Chronic	3	H412
Hazardous for the ozone layer	Ozone 99	1	H420

• Transport Information: UN 9274

Discovery and Applications

Dichlorofluoroethane, commonly known as Freon-12 or R-12, is a chlorofluorocarbon (CFC) with the chemical formula C2Cl2F2. It was first synthesized in the 1920s as part of a broader effort to develop safer and more efficient refrigerants and propellants for aerosol sprays. The discovery of dichlorofluoroethane marked a significant advancement in chemical engineering and refrigeration technology, as it provided a non-toxic and non-flammable alternative to the ammonia and sulfur dioxide systems commonly used at the time.

The initial commercial production of dichlorofluoroethane began in the 1930s, spearheaded by the American chemical company DuPont. The compound quickly gained popularity due to its stability, low boiling point, and effectiveness as a refrigerant. It was used extensively in air conditioning systems, refrigeration units, and as a propellant in aerosol products. Its properties made it particularly suited for applications requiring a stable and efficient refrigerant that could operate under a range of temperatures without posing a significant risk to human health or the environment.

In refrigeration, dichlorofluoroethane is favored for its excellent thermodynamic properties, which allow it to absorb heat effectively. This makes it highly efficient for use in various cooling applications, from domestic refrigerators to large-scale industrial cooling systems. The widespread adoption of dichlorofluoroethane in refrigeration contributed to the development of modern air conditioning systems, which transformed residential and commercial environments by providing controlled temperature and comfort.

Apart from its use in refrigeration, dichlorofluoroethane served as a propellant in aerosol products, such as sprays for personal care, household cleaning, and insecticides. Its ability to vaporize quickly at room temperature made it an ideal choice for delivering products in a fine mist. This contributed to the growth of the aerosol market in the mid-20th century, enhancing the convenience of various consumer goods.

However, by the late 1970s and early 1980s, concerns emerged regarding the environmental impact of chlorofluorocarbons, particularly their role in ozone depletion. Studies revealed that when CFCs are released into the atmosphere, they can ascend to the stratosphere, where ultraviolet radiation breaks them down, releasing chlorine atoms that catalyze the destruction of ozone molecules. This led to increased scrutiny and regulatory measures aimed at phasing out the use of dichlorofluoroethane and other CFCs.

In response to these environmental concerns, the Montreal Protocol was established in 1987, an international treaty designed to phase out substances responsible for ozone depletion. Following this treaty, the production and consumption of dichlorofluoroethane were significantly reduced, and alternatives were sought. Hydrofluorocarbons (HFCs) and other more environmentally friendly refrigerants began to replace dichlorofluoroethane in various applications. These alternatives do not contribute to ozone depletion, although some still pose global warming potential, prompting ongoing research for even greener options.

In summary, dichlorofluoroethane played a critical role in the advancement of refrigeration and aerosol technologies throughout the 20th century. Its discovery and subsequent applications revolutionized how cooling and dispensing systems operated, providing safer and more efficient solutions for consumers. However, environmental concerns regarding its impact on the ozone layer led to its phase-out under international agreements, highlighting the need for sustainable practices in chemical manufacturing and usage.

References

2023. Speed of Sound in Gaseous 1,1-Difluoroethene (R1132a) at Temperatures Between 193 K and 383 K at Pressures up to 3 MPa. International Journal of Thermophysics, 44(5).
DOI: 10.1007/s10765-023-03198-y

2024. Impact of Fluorides and Fluorocarbons Contamination on the Environment and Human Health. Environmental Science and Engineering, 4.
DOI: 10.1007/978-981-97-7733-4_4

2018. The development of environmentally acceptable fluorocarbons. Critical Reviews in Toxicology, 48(8).
DOI: 10.1080/10408444.2018.1504276.