Study on Competitive Adsorption and Displacing Properties of CO₂ Enhanced Shale Gas Recovery: Advances and Challenges

Table 1

Typical models for monolayer and multilayer adsorption.

Model	Formula	Reference
Langmuir		[71]
BET		[72]
Freundlich		[73]

where is the gas adsorption, mg/g; is the pressure, bar; is the Langmuir maximum adsorption, mg/g; is the Langmuir constant; is the saturation pressure, bar; is the constants of BET isotherm; is the maximum uptake, mg/g; and and are the constants of Freundlich isotherm.