CO2 absorbent

[James] [???]

 

=== Unfinished ===

Trichloroethylene reaction with sodalime

Types of CO2 absorbent

Sodalime

• Calcium hydroxide (80%)
• Water (15%)
• Sodium hydroxide (4%)
  --> Catalyst for CO2 absorbing property
• Potassium hydroxide (1%)
• Indicator (ethyl violet or phenelpthalein) (???spelling)
• Small amounts of silica to produce calcium and sodium silica

Baralyme

• Calcium hydroxide
• Barium hydroxide
  --> Active component in CO2 absorption
• May also contain KOH

Calcium hydroxide lyme

• Primarily calcium hydroxide and calcium chloride
• No KOH

 

 

=======

[James] [???]

Trichloroethylene

Trichloroethylene must not be used with sodalime

Heat in presence of alkali decomposes trichloroethylene to HCl + dichloroacetylene
--> Combine with O2 to form carbon monoxide and phosgene
--> Carcinogenic and hepatotoxic

 

Halothane

CO2 absorbents degrade halothane by dehydrofluorination reaction
--> Forms bromochlorotrifluoroethane or bromochlorodifluoroethylene (BCDFE)

BCDFE is potential nephrotoxin

 

 

Sevoflurane and CO2 absorber fires

Sevo reacts chemically with absorbents (especially baralyme)
--> Carbon monoxide and flammable organic compounds methanol and formaldehyde
--> Also produce heat which accelerate the reaction
--> At high temperature, can spontaneously combust

Most likely with desiccated absorbents