The inhibition of the combustion of carbon and carbon monoxide

✍ Scribed by Bridger, G. W. ;Appleton, H.

• Publisher: Wiley (John Wiley & Sons)
• Year: 1948
• Weight: 614 KB
• Volume: 67
• Category: Article
• ISSN: 0368-4075
• DOI: 10.1002/jctb.5000671207

✦ Synopsis

Abstract

The presence of small concentrations of inhibitors (CCl4, Cl2 and HCL) in the air passing into a bed of burning coke is found to increase the CO content of the combustion gases at the expense of the CO2. With sufficient inhibitor (> 2.0% CCL4) the effect amounts to almost complete suppresion of the reduction of CO2. The effect is not due to a promotion of the reduction of CO2, this reaction proceeding only to a very smal extent under the conditions of the experiments. Further experiments show that inhibitors cdan prevent the oxidation of 95% of the CO at 1000° in the presence of excess oxygen. if the inhibitor (chlorine) is present in the inlet gases in a concentration greater than a sharply defined critical value (c.0.5%). This is an extension to a high temperature region of the well‐known action of halogen compounds on CO oxidation at lower temperatures. The inhibition of the oxidation of carbon monoxide is found to be most effective when the area of surface of the silica reation vessel is greatest and also when the CO and Cl2 are preheated together; in an empty reaction tube and with the CO preheated separately from the Cl2, no critical Cl2, concentration is found and inhibition is poor.

The conclusions from the work on the oxidation of CO are applied to the earlier experiments on coke combustion in the presence of inhibitors; it is inferred from the absence of CO2 in the combustion gases produced in inhibited coke combusion, that CO2 is not formed as a primary product of the interaction between carboon and oxygen, but is always produced by the oxidation of carbon monoxide. This conception is discussed with reference to the “two‐zone theroy” of combustion.