Adsorption isotherms
Answers
Answer:
Explanation:
Adsorption isotherms
Adsorption isotherm is a graph or a relation between the amounts of adsorbate adsorbed on the surface of adsorbent and pressure at a constant temperature.
Different adsorption isotherm was studied by different scientists-
Freundlich Adsorption Isotherm
Freundlich proposed an empirical relationship between amount of gas adsorbed by unit mass of adsorbent and pressure at a particular temperature. Following equation was proposed for freundlich adsorption isotherm-
x/m= k. p1/ n (n > 1)
x is the mass of the gas adsorbed
m is the mass of the adsorbent
p is the pressure
k and n are constants which depends on the nature of the adsorbent and the gas at a particular temperature.
Taking log of the above equation, the following equation will be observed
log x/m = log k +1/n log p
x/m is plotted on y axis and log p is on x axis. If straight line is observed than only freundlich isotherm is verified.
Slope gives 1/n and intercept gives log k. The value of 1/n varies from 0 to 1.
If 1/n is 0, adsorption is independent of pressure.
If 1/n is 1, adsorption changes with pressure.
Answer:
Isotherms. The adsorption of gases and solutes is usually described through isotherms, that is, the amount of adsorbate on the adsorbent as a function of its pressure (if gas) or concentration (for liquid phase solutes) at constant temperature. ... To date, 15 different isotherm models have been developed.
