CH107191A - Process for increasing the porosity of decolorizing carbons. - Google Patents

Description

  

  Process for increasing the porosity of decolorizing carbon. As is well known, the effectiveness of decolorizing charcoal is based on its adsorption capacity, which is conditioned on the one hand by the surface activity in the sense of Gibbs' theorem and on the other by capillarity phenomena due to the porosity of the charcoal particles.

   The process for the production of coals with high surface activity are generally based on the fact that organic substances at higher temperature, mostly in the presence of alkaline substances such as hydroxides, carbonates, sulfides and the like. a., of alkalis or alkaline earths, or of acidic substances such as acids, or substances that have an acidic effect at a higher temperature, such as chlorides, sulfates, phosphates of ammonium, aluminum, zinc, iron and the like, are heated with avoidance of air.

   In order to quickly remove the distillation organs that occur during the charring process, gases or vapors such as water vapor, carbon dioxide, nitrogen, chlorine and the like are passed many times during the charring process. a. through the crowd. In individual cases one has the surface activity of the. Coal, especially for the purpose of revitalizing used coal, sought to be increased by heating the coal to 200 to 400, possibly with the admission of air, or by letting dissolved oxidizing agents act on the coal.



  The invention relates to a process by which a particularly high porosity of the coal is achieved. It is based on fully formed adsorption coal of any origin and manufacture and consists in passing a mixture of oxygen and at least one gaseous substance that prevents combustion, for example a gas or steam, over the coal heated to over 500 for a longer period of time whose oxygen content is so low that

   that the oxidation of the carbon particles caused by the same takes place gradually and without visible signs of combustion only after the carbon structure has completely penetrated the mixture.



  The present process is expediently carried out in such a way that the gas or steam parchment is slowly passed through in a closed space which is heated to over 500 'and contains the coal, whereby one merely needs to be careful has that during this process no visible burns or burns on the glowing coal. Fire phenomena are noticeable. In this case the concentration of oxygen would have to be reduced. The starting material can be any decolorizing charcoal, for example charcoal, animal charcoal and the like. a., apply.

    For the preparation of the gaseous mixture one will not use pure oxygen, but expediently air; all oxygen-free or low-oxygen gases or gases that prevent combustion are suitable as dilution gases or vapors, for example exhaust gases from fires. Generators, lime kilns, etc.



  The products produced by the present process differ from the starting material in that they have a significantly higher absorption capacity for gases, vapors or dissolved substances.

 

Claims (1)

PATENT CLAIM: Process for increasing the porosity. of decolorizing charcoal, characterized in that a mixture of oxygen and at least one gaseous substance preventing combustion is passed over a dsorptionscolile of any manufacture and origin for a longer period of time at a temperature above 50l1, the oxygen of which , keep it so low The choice is that the oxidation of the carbon particles occurring through them takes place only after the carbon structure has been completely penetrated by the gaseous mixture and without any visible signs of combustion. '