Accession Number : ADA306260

Title :   Model of Chlorocarbon (CFC-12) Chemisorption on Solid Rocket Motor Alumina Exhaust Particles.

Descriptive Note : Master's thesis,

Corporate Author : AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH

Personal Author(s) : Lund, Gary E.

PDF Url : ADA306260

Report Date : DEC 1995

Pagination or Media Count : 142

Abstract : Solid Rocket (SRMs) that power Titan IV rockets and Space Shuttles, exhaust large quantities of potentially ozone damaging pollutants directly into the stratosphere, while in powered flight. In the past, studies on potential stratospheric impact of the exhaust products from aluminum/ammonium perchlorate based SRMs have focused on the effect of gaseous HCl from SRMs on the stratosphere. Until recently, the impact of heterogeneous chemistry on stratospheric ozone was believed to be relatively insignificant. This research investigates the potential heterogeneous process of CFC-12 dissociative chemisorption on alumina surfaces and the release of reactive halogen species known to destroy ozone. Through a PM3 semi-empirical computational study of small alumina surface 'clusters,' dissociative chemisorption and desorption of CFC-12 was investigated. It was determined that CFC-12 does chemisorb but does not dissociate or desorb thermally based on our models. Follow-on work involving larger alumina structures should be investigated.

Descriptors :   *PARTICLES, *ALUMINUM OXIDES, *HALOGENATED HYDROCARBONS, *ROCKET ENGINES, *CHLORINE, *CHEMISORPTION, *EXHAUST GASES, DAMAGE, STRUCTURES, REACTIVITIES, SOLIDS, SURFACES, CHEMISTRY, FLUORINE, SPACE SHUTTLES, HETEROGENEITY, POLLUTANTS, DISSOCIATION, DESORPTION, OZONE, HALOGENS, STRATOSPHERE, AMMONIUM PERCHLORATE, PERCHLORATES, COMBUSTION PRODUCTS.

Subject Categories : Physical Chemistry
      Organic Chemistry
      Rocket Engines
      Astronautics

Distribution Statement : APPROVED FOR PUBLIC RELEASE