Soda lime

Soda lime is used in anesthesia machines and rebreathers ( or rebreather diving rebreathers ) for binding contained in the exhaled carbon dioxide to prevent the harmful effects of too high Kohlenstoffdioxidgehalts in the inhaled air. Soda lime is also used in space travel.

In medicine and diving, a mixture of calcium hydroxide Ca (OH) 2 and sodium hydroxide NaOH is used before and potassium hydroxide KOH, and barium hydroxide Ba (OH ) 2 Soda lime for chemical bonding of carbon dioxide was introduced in 1924 by Ralf Waters.

The following chemical reactions between the soda lime and carbon dioxide are operating:

1:

2:

3:

100 g of sodium hydroxide can bind up to 23 liters of carbon dioxide. Average absorbers can absorb 10-15 liters per 100 g. The optimal granule cross-section is 2.5 mm. The scrubber is mixed with a pH indicator which changes its color at a low pH - value of white to purple, indicating that the absorber has been consumed.