Mixing NaOH

HOH Cells - Mixing the Caustic Soda

24-12-2007

Balancing your system to operate at the most appropriate amperage can be a bit tricky, so I've detailed for you here the process I use to assist with this.

REMEMBER: CAUSTIC SODA (NaOH, Sodium Hydroxide) is nasty stuff. Eye and Skin Protection should be worn when working with this chemical and please be sure to refer to the Materials Safety Data Sheet (MSDS) before using. Here is a link for your reference http://www.physchem.ox.ac.uk/MSDS/SO/sodium_hydroxide.html

	Using a small set of scales.
	Tare your cup weight or deduct from total
	For a 10% concentration of NaOH add 100 grams of dried flakes to a suitable plastic container.
	Measure 1000g of distilled / dematerialised water (1 litre)
	Slowly and carefully add the 100grams of NaOH to the water, do not add water to the NaOH flakes. Make sure you use a suitable plastic container for this. Using a glass container is not recommended as there is heat generated as the solution is mixing which may crack a glass container. Ensure you have carefully followed the safety instructions in the Materials Safety Data Sheet (MSDS) Continually stir preventing the solid from forming of the bottom.
	Allow to sit and until dissolved and cooled before use
Add this mixture to your cell by filling until the cell itself is just submersed. Add additional pure water to this mixture to bring the operating amperage when cold to approximately 10AMP when cold. Higher Concentration will result in current run away effect unless the current is otherwise limited.