Oil-grease adsorption

Adsorption techniques have been successful in removing oil-grease. Clay minerals have been the most widely used absorbent because its cost is low and they can be reached easily. Oil-grease adsorption on various sorbents has been studied by many researchers [1-6]. 

The studies relating the effect of temperature on adsorption was carried out at eight different temperatures (natural illite clay, 110°C, 200°C, 350°C, 450°C, 550°C, 750°C, 900°C) with a oil-grease concentration of 1,000 mg L and 5 g of illite clay sample, keeping the other parameters constants. Figure 20.2 shows oil-grease adsorption as a function of temperature. 

Adsorption of oil- grease for seven different particle sizes on thermally activated illite clay (>710 pm 710-600 pm 600-425 pm 425-355 pm 355-150 pm 150-75 pm <75 pm) was studied keeping the other parameters as constant. The result of variation of this particle sizes on oil-grease adsorption show in Table 20.3. 

The adsorption capacity of thermal activated illite is increased as 5.5% according to natural illite mineral. It has seen that there is on significant loss of adsorption capacity of illite at about 550°C. The capacity of oil - grease adsorption is... 

Abstract The aim of this work was to study the simultaneous effect of amount of clay, activation temperature, contact time, pH, and size of the adsorbent on the retention of oil-grease thermally activated illite by adsorption. The values obtained for the percentage of oil-grease removed ranged from 93.87% for 110°C up to 66.73% for 900°C. The adsorption experiment showed surface that the stronger heat treatment the most effective adsorption of oil-grease. 

Figure 20.5 shows the effect of contact time and percentage adsorption oil-grease on the removal by thermally activated illite. 

In the detergency process, fatty materials (i.e. dirt, often from human skin) are removed from surfaces, such as cloth fibres, and dispersed in water. It is the surfactants in a detergent which produce this effect. Adsorption of the surfactant both on the fibre (or surface) and on the grease itself increases the contact angle of the latter as illustrated in Figure 4.7. The grease or oil droplet is then easily detached by mechanical action and the surfactant adsorbed around the surface of the droplet stabilises it in solution. 

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