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Question
What do you understand by activation of adsorbent? How is it achieved?
Solution 1
By activating an adsorbent, we tend to increase the adsorbing power of the adsorbent. Some ways to activate an adsorbent are:
(i) By increasing the surface area of the adsorbent. This can be done by breaking it into smaller pieces or powdering it.
(ii) Some specific treatments can also lead to the activation of the adsorbent. For example, wood charcoal is activated by heating it between 650 K and 1330 K in vacuum or air. It expels all the gases absorbed or adsorbed and thus, creates a space for adsorption of gases.
Solution 2
Activation of an adsorbent means increasing it’s adsorbing power by increasing the surface area of the adsorbent by making it’s surface rough, by removing already adsorbed gases from it and by subdividing the adsorbent into smaller pieces or grains.
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