"Adsorption" experiment

How to purify air using active charcoal

This spec­tac­u­lar ex­per­i­ment shows how air is pu­ri­fied in gas masks and oth­er pu­ri­fy­ing de­vices, us­ing ac­tive char­coal.

Reagents and equip­ment:

  • cop­per;
  • con­cen­trat­ed ni­tric acid;
  • ac­tive char­coal;
  • con­ic flasks (3);
  • stop­pers (2);
  • stop­per with a gas pipe (1).

Step-by-step in­struc­tions

Pre­pare three flasks, two with stop­pers and one with a gas pipe. Place cop­per in the flask with a gas pipe and pour in con­cen­trat­ed ni­tric acid. A brown gas starts to be re­leased vi­o­lent­ly – ni­tro­gen diox­ide, which we pour into the two flasks and seal them with stop­pers. Af­ter a while, when we are sure that our sys­tems are her­met­ic, we add tablets of ac­tive char­coal to one of the flasks.

Pro­cess­es de­scrip­tion

Sev­er­al min­utes lat­er, in the flask with the ac­tive char­coal, the gas will grad­u­al­ly start to dis­ap­pear. The ab­sorp­tion of the gas by the ac­tive char­coal takes place. Ad­sorp­tion is a process when the sur­face lay­er of a liq­uid or sol­id body – an ad­sor­bent – takes in gas­es, va­pors and sub­stances from a sub­stance or gas mix­ture. Ac­tive char­coal is a good ad­sor­bent, and de­pend­ing on the tech­nol­o­gy of its man­u­fac­ture, the sur­face of one gram of char­coal that can ad­sorb sub­stances reach­es 1500 m². Ac­tive char­coal is wide­ly used in medicine and tech­nol­o­gy for the pu­rifi­ca­tion, sep­a­ra­tion and ex­trac­tion of var­i­ous sub­stances.

Safe­ty pre­cau­tions

This ex­per­i­ment uses poi­sonous sub­stances. Do not try it at home.

Warn­ing! Sub­stances of this ex­per­i­ment are tox­ic and high­ly dan­ger­ous for your health. Do not try this at home. Only un­der pro­fes­sion­al su­per­vi­sion.

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