Accession Number : ADA149041


Title :   The Reaction of Oxygen-Nitrogen Mixtures with Granular Activated Carbons below the Spontaneous Ignition Temperature


Corporate Author : GEO-CENTERS INC NEWTON CENTRE MA


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a149041.pdf


Report Date : Aug 1984


Pagination or Media Count : 28


Abstract : The presence of oxygen in the carbon network of gas adsorbent charcoals presents a research problem of long standing. Four pertinent topics now concerned with the oxygen-charcoal reactions are: a) activation of the adsorbent charcoals (manufacture), b) regeneration processes (applications), c) the spontaneous ignition temperature (safety considerations), and d) the use of charcoals as catalyst carriers and impregnation supports. It is desirable to have a deeper knowledge of the initial surface composition of a charcoal that is to be used in a specific process. Thermal desorption behavior can supply such information. The results to be reported cover three characteristic temperature- dependent phenomena: 1) an anomalous desorption in which a number of maxima occur in the concentrations of CO and CO2; 2) the formation of a surface barrier causing a decay in the CO and CO2 concentrations with the first-order rate constants at constant temperature; and 3) the attainment of a reproducible spontaneous ignition temperature (SIT) during programmed heating at a linear rate. These observations indicate a considerable complexity in the surface structure of an activated carbon.


Descriptors :   *ACTIVATED CARBON , *SURFACE ACTIVE SUBSTANCES , *CHEMISORPTION , TEMPERATURE , NITROGEN , OXYGEN , IGNITION , CARBON MONOXIDE , CARBON DIOXIDE , DESORPTION , OXIDATION REDUCTION REACTIONS , SPONTANEOUS COMBUSTION , GAS FLOW , PARTIAL PRESSURE , CHARCOAL , HEAT OF ACTIVATION , HEAT OF COMBUSTION


Subject Categories : Organic Chemistry
      Physical Chemistry


Distribution Statement : APPROVED FOR PUBLIC RELEASE