Ascarite scrubber

Now, let s imagine the gas is delivered to a patient through a gas scrubber filled with Ascarite to remove the carbon dioxide. Ascarite is sodium hydroxide on asbestos. Ascarite II uses silica instead of asbestos. As the gas flows over this high-surface-area medium, carbon dioxide in the sample reacts with the sodium hydroxide to give the nonvolatile product sodium bicarbonate. 

CO2 removal agent A CO2 scrubber is used in the purification tube (16) to remove any traces of CO2 from the reference gas. Soda lime and Ascarite (sodium hydroxide coated silica Thomas Scientific Inc., Swedesborough, NJ, USA) are good choices. 

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