A new adsorbing material, the monolith of activated charcoal, is used for the adsorption of volatile organic compounds (VOCs) and their desorption by electrothermal heating using Joule effect. The word "monolith" is proposed by analogy with the supports of catalysts for car. The monolith, obtained by agglomeration of activated charcoal in powder with a binder, appears under shape of a parallelepipede of square section including four hundred parallel channels. Equilibrium isotherms for toluene toluene on a piece of this material at various temperatures were measured by the gravimetric method and correlated by the equation of Toth. The adsorption breakthrough fronts measured on the monolith show that it is effective and that the stoechiometric capacity is in agreement with the measured isotherms. Desorption is performed by heating of the monolith by means of a continuous electric current flowing transversely to the channels. The curve of desorption shows that the toluene is desorbed with a factor of concentration which exceeds forty in first ten minutes. Examples of adsorption and desorption on the binary mixture toluene/butanol are also presented.
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