Characteristics of Adsorbable Solutes

In moving to a study of adsorption from solution, we would seem to need a new and different set of ground rules. The deep seated differences found between the adsorptive behavior of vapors versus solutes can be traced to a different character of the interface. In the case of the carbon ( gas interface, the gas space serves primarily as a reservoir from which molecules are delivered to, or received from, the interface. 

The carbon liquid interface presents a definite contrast here the liquid side of the interface exerts a number of positive influences as shown in Table 2 3. The intensity, magnitude, and direction of influence will vary according to the specific assortment of solutes and solvents the net resultant can serve to augment, modify, or nullify the attractive forces exerted by the carbon side of the interface. 

FACTORS INFLUENCING ADSORPTION AT CARBON LIQUID INTERFACE 

A salient difference in the adsorption of solutes versus gases and vapors is found in the altered role of temperature. An elevation in temperature increases the escaping tendency of a vapour or gas from the interface and invariably diminishes the adsorption. Similar action operates at the carbon liquid interface, but here it is often dwarfed by the influence of temperature on solvent affinities. This should not be taken to mean that temperature is without influence on adsorption from solution certainly, temperature can have much influence on the magnitude and direction of many factors shown in Table 2 3 and thereby alter the course of an adsorption. But the resulting action is quite specific (Table 2 4), many instances are 

INFLUENCE OF TEMPERATURE ON ADSORPTION OF DYES (Equilibrium concentration, 0.1 millimole/liter) 

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