The catalytic behaviour of NiFe₂-xCr_xO₄ (0.0 ≤ x ≤ 2.0) during the thermal decomposition of ammonium perchlorate, polystyrene and their composite propellants

Abstract

NiFe₂O₄, NiFeCrO₄ and NiCr₂O₄ catalysts have been prepared by solid state reaction and characterised by using chemical analysis and X- ray diffraction techniques. Electrical conductivity and thermoelectric power measurements have shown that the catalysts are p-type semiconductors. The thermal decomposition of ammonium perchlorate, polystyrene and a composite propellant of ammonium perchlorate and polystyrene has been studied in the presence of these catalysts using thermogravimetric analyser. The effectiveness of the catalysts during the decomposition of ammonium perchlorate (AP),

polystyrene (PS ) and a composite propellant of AP+PS has the following order respectively: NiCr₂O₄ > NiFeCrO₄ >NiFe₂O₄;NiFeCrO₄ > NiCr₂O₄ > NiFe₂O₄ and NiFeCrO₄ > NiCr₂O₄ > NiFe₂O₄.