Thermal analysis in reactive atmospheres

Abstract

By using reactive atmospheres, the area of aplb]ication of thermal analysis is expanded considerably to cover many aspects of high temperature research into fuels, extractive metallurgy, materials and catalysts. This article reviews the design of apparatus and its application in kinetic and thermodynamic studies involving atmospheres such as H2, CO, N2, NH3, CO2, H20, SO2or3~ H2 S, $2. C12, HCI, F2 and HF at low or high pressures and as low pressure plasmas. Apart from gas-solid reactions, the important influence of a controlled product gas atmosphere on decomposition reactions is discussed also. Gas-solid adsorption and solubility studies are not included. John Wiley & Sons, Limited, ChichesterAkaddmiai Kiad6, Budapest GIMZEWSKI: ANALYSIS IN REACTIVE ATMOSPHERESTable I Areas of application of thermal analysis using reactive atmospheres ATMOSPHERE APPLICATIONS 02 H2, CO N2, NH3, NO2 C02 H20 802 or3 H2S 02, HCI etc F2, HF etc Plasmas Combustion, extractive metallurgy, oxidation stability tests, carbon analysis. Extractive metallurgy, coal hidrogenation, catalysts, materials science, hydrogen storage. Nitriding using N 2 or NH3, decomposition of catalysts, and propellants in NH3, extractive metallurgy using NO2.Exploitation and analysis of carbonate minerals, processing fuel gases, corrosion.Coal gasification, materials science, reversible dehydration reaction analysis of plaster.Cleaning combustion gases, extractive metallurgy.Cleaning fuel gases, corrosion.Extractive metallurgy, analysis of ceramics.Nuclear fuel processing. Materials science Experimental ApparatusThermal analysis has been performed in gases and vapours at low and high pressures and in low pressure plasmas. Plasmas and vapours pose specific problems discussed below, but otherwise the apparatus design is dictated by the corrosive nature of the atmosphere, its pressure and its flow arrangement. A flowing atmosphere is preferred at normal and high pressures to facilitate mass transfer but at low pressures the atmosphere is usually static. Below, corrosion problems are discussed for furnaces, thermocouples and thermobalances, and the difficulties in generating and using controlled atmospheres are considered separately for gases, vapours and plasmas.s ThermalAnal. 33, 1988

Al2O3/Ni functionally graded materials (FGM) obtained by centrifugal-slip casting method

“…There is little research on the analysis of the sintering process conducted in reducing atmosphere. For this reason, DTA/TG analysis gives important information about thermal degradation of additives used in shaping process as well as about the thermal behavior of samples in the inert and reductive atmospheres [15][16][17][18]. Furthermore, coupling mass spectrometer with thermobalance allows to detect type of gases released from samples.…”