Effect of Carbon Dioxide on the Reactivity of the Oxidation of Boron Particles. Issue 4 (5th February 2014)

• Record Type: Journal Article
• Authors: Li, Heping; Ao, Wen; Wang, Yang; Zhou, Hua; Liu, Jianzhong; Zhou, Junhu
• Is Part Of: Propellants, explosives, pyrotechnics. Volume 39:Issue 4(2014:Aug.)
• Page Start: 617
• Page End: 623
• Publication Date: 2014-02-05
• Subjects: Propellants -- Periodicals; Explosives -- Periodicals; 662.2
• DOI: 10.1002/prep.201300180
• Languages: English
• ISSNs: 0721-3115

Abstract

<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <p>Carbon dioxide produced in the primary combustion of propellants apparently affects the combustion of boron. In this study, the thermodynamic and kinetic properties of the combustion of boron particles in a CO<sub>2</sub> environment (solely or as a mixture with other gases) were investigated using thermogravimetric analyses. For the combustion of boron in an atmosphere containing 10 % oxygen, in addition to a large initial weight gain, a second increase in weight was observed when the temperature reached 1150 °C. However, when the combustion was carried out in pure CO<sub>2</sub> atmosphere, the sample lost weight at temperatures above 1300 °C. The above results indicated that the layer of boron oxide covering the boron particles had a significant effect on the combustion process. With a limiting concentration of O<sub>2</sub> (10 %), the initial temperature and effective activation energy slightly decreased as the content of CO<sub>2</sub> increased from 0 to 30 %. However, a further increase in the CO<sub>2</sub> content (50 %) increased the effective activation energy, indicating the inhibitory effects of CO<sub>2</sub> at higher concentrations. Furthermore, the weight and the rate of weight gain gradually increased with increasing CO<sub>2</sub> content. This behavior was attributed to the improvement in the diffusion of the oxidant. This study conclusively revealed that the inclusion of an optimal level of CO<sub>2</sub> in a reaction environment containing O<sub>2</sub> facilitated the combustion of boron particles.</p> </abstract>