An alkali metal can be any of the six elements found in the first column of the periodic table, namely: cesium, francium, lithium, potassium, rubidium, and sodium.
Properties of Alkali Metals
Alkali metals are very reactive—even at standard pressures and temperatures—because of their low ionization energy. This means that only a small amount of energy is necessary to remove the outermost and most loosely bound electron in the atom. They also have bigger atomic radii and are more likely to donate their electrons in chemical reactions.
Here are some other crucial properties of alkali metals to keep in mind:
They’re less dense compared to most elements.
They have low melting and boiling points.
They’re silvery in color, except for cesium, which appears golden.
They’re soft and ductile. They can be easily cut, except lithium which is harder than the others but can still be cut.
Hazards of Working with Alkali Metals
Due to the highly reactive nature of alkali metals, they need to be handled with care. Alkali metals form caustic metal oxides when exposed to air. Cesium and rubidium, in particular, will combust spontaneously when exposed to room-temperature air.
Alkali metals also react violently with water, releasing metal hydroxides and hydrogen gas. This hydrogen may ignite, causing an explosion or a fire with. The fumes can irritate or burn the eyes, skin, and lungs. Furthermore, alkali metals are incompatible with Teflon, acids, and halogens.
When handling alkali metal for experiments or for industrial purposes, protective gear must be worn at all times. This includes safety glasses or chemical splash goggles, a face shield, rubber or leather gloves, fire-resistant clothing, and fully enclosed leather shoes.
Cleaning Up Alkali Metals
There are several ways to clean up alkali metals in residual or larger quantities. By far, the safest and most cost-effective solution is the use of superheated steam. Here are some of the benefits of using this method:
The equipment from Creative Engineers only takes a week or two to install and is reusable
Reactions are controllable and can be easily stopped—with a typical response time of less than one minute
Projects can be finished quickly because our equipment operates at a rate of several hundred pounds per hour
It does not require the use of organics, which can cause fires or regulatory issues
It also does not require the use of potentially toxic substances
It can also be used to clean equipment or tools that have been used to handle alkali metals, including pumps, piping, valves, and tanks
The high temperatures make it impossible for moisture to condense into a liquid phase form of water allowing the reaction to be controlled and preventing runaway reactions
Emergency Response
To prevent reactions with air and water, alkali metals are usually kept under mineral oils or inert gas. They’re also typically used in airtight containers such as glove boxes with an inert atmosphere.
In case of accidents—with fire as the most likely incident—an immediate response is necessary to prevent further damage. Use powder-based fire extinguishers ( class D) and avoid using units that contain water or carbon dioxide since alkali metals are highly reactive to these substances. If it’s impossible to extinguish the fire safely, evacuate the area right away.
Conclusion
Alkali metals are highly reactive. When handling alkali metals for experiments or other commercial uses, proper care is necessary. Cleanup is easier and more cost-effective with the use of specialized equipment operating with a superheated steam process. It ensures a safer, faster, and more effective alkali metal cleanup.
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Specialists In Alkali Metal Engineering
Creative Engineers Inc has spent many years working with alkali metals (sodium, potassium, lithium). Our experts have been involved in many projects, with experiences that include alloys such as sodium-potassium alloy and lithium-aluminum.
We can provide you with specialists for consultation, training, documentation, and engineering processes for these unique materials. Contact us to learn more!