Method for the volatile organic compounds adsorption capacity prediction based on filling adsorption

A method for volatile organic compounds adsorption capacity prediction based on filling adsorption, comprising the following steps:

• (1) providing two or more porous materials with concentrated pore size distribution as model adsorption materials;
• (2) testing pore structure parameters, testing adsorption isotherms of the model adsorption materials for specific VOCs at specific adsorption temperatures, and obtaining an adsorption capacity Q of the model adsorption materials under different pressures;
• the pore structure parameter comprises a pore size distribution, a pore volume in a specific pore size range, and a specific surface area in a specific pore size range;
• (3) obtaining a corresponding pressure interval when the filling adsorption occurs in each of the model adsorption materials according to the adsorption isotherms, taking an intermediate value of the pressure interval as a critical pressure point PC, making a critical pressure point PC correspond to the intermediate value of the pore size distribution of the adsorbent material, taking the intermediate value of the pore size distribution as the critical pore size DC at which filling adsorption can occur at the critical pressure point PC;
• (4) taking the critical pore size DC as a demarcation point, obtaining a pore volume VC of the pores below the critical pore size DC and a specific surface area of the pore SC above the critical pore size DC, respectively, according to the pore structure test results of the adsorption materials;
• (5) the adsorption capacity Q, pore volume VC and specific surface area SC meet the prediction equation Q=f(VC, SC) of volatile organic compounds adsorption capacity based on filling adsorption, i.e. formula 1:
• Q
• =
• f
• ⁡
• (
• Vc
• ,
• Sc
• )
• =
• a
• ×
• ρ
• ×
• Vc
• +
• b
• ×
• Sc
• ,
• i
• .
• e
• .
• ;
• (
• formula
• ⁢
• 1
• )
• wherein, Q is the adsorption capacity of VOCs by adsorption materials per unit mass, g/g;
• a is the coefficient of filling adsorption, no unit;
• ρ is the density of liquid VOCs at specific adsorption temperature, g/cm3;
• VC is the pore volume of the pores below the critical pore size DC, cm3/g;
• b is the adsorption amount of VOCs per unit specific surface area through covering adsorption, g/m2;
• SC is the specific surface area of the pores above the critical pore size DC, m2/g;
• (6) testing the other adsorption materials at the same adsorption temperature, according to the steps (2)~(4), obtaining the adsorption capacity Q, pore volume VC and specific surface area SC of the remaining adsorption materials, introducing these data into formula 1 to obtain the specific values of coefficients a and b, and obtain the prediction equation of adsorption capacity of volatile organic compounds based on filling adsorption.