Argon (Ar) in Water Treatment
Quick Answer
Argon (Ar) is a noble gas with atomic number 18. PubChem lists its standard state as gas and its relative atomic mass as 39.9.
Argon is not normally a treatment target in water. If a dissolved noble gas must be controlled in a specialized process, gas-transfer operations such as aeration, vacuum degassing or membrane contactors are more relevant than particle filters.
Interesting Facts
- Argon makes up almost 1% of Earth’s atmosphere, making it far more abundant than carbon dioxide in dry air.
- Its name comes from a Greek word meaning “inactive,” reflecting its reluctance to form compounds.
- A particle filter cannot remove a dissolved gas; specialised control relies on gas transfer, pressure and membrane-contact area.
Water-treatment Design Implications
An element name alone is not enough to select treatment equipment. Confirm chemical form or speciation, total and dissolved concentration, pH, alkalinity, competing ions and the product-water target. Send the water-analysis results to Watermart to identify additional testing and shortlist processes before equipment is specified.
Summary Data Sources
Argon (Ar)
1. Basic Information
| Properties | Value |
|---|---|
| Atomic Number | 18 |
| Symbol | Ar |
| Atomic Mass | 39.948 g/mol |
| Category | Noble Gas |
2. Physical and Chemical Properties
Argon is a colorless, odorless, and tasteless noble gas. Some important properties include:
- Boiling point: -185,7°C
- Melting point: -189°C
- Density: 1.78 g/L at 0°C
- Water solubility: 61 mg/L at 20°C
- Very stable and chemically inert
3. Presence in Water and Health Effects
Argon is present in natural water in low concentrations, about 0.45 mg/L. Due to its inert nature, argon has no direct health effects on humans when present in drinking water. However, in high concentrations in air, argon can displace oxygen and cause asphyxia.
4. Water Treatment Applications and Removal Methods
Although argon is rarely a primary target in water treatment, several methods can be used to remove it if needed:
- Aeration: Effective for removing dissolved gases including argon
- Vacuum degasification: Can remove argon and other gases
- Degas membranes: Allows selective separation of gases from water
In most cases, removal of argon from water is not required due to its low concentration and inert nature.
5. Industrial Use in Water Treatment
Although argon is not commonly used directly in water treatment, the gas has several related applications:
- Used as a shielding gas in the welding of stainless steel water treatment equipment
- As an inert gas in laboratory analysis of water quality
- In the manufacture of ozone for water disinfection, argon is sometimes used as a carrier gas
8. Environmental Impact and Sustainability Considerations
Argon is a non-toxic natural gas and does not contribute to global warming or ozone depletion. Industrial argon production is generally done through liquid air distillation, which is relatively energy efficient. The use of argon in water-related applications generally has minimal environmental impact.