The interaction of different metal carbides, namely Cr7C3, Fe3C, TiC, ZrC, NbC, TaC, MoC, WC, VC and HfC with NaCl in a temperature range 900-1200 K in flowing oxygen has been studied. The thermogravimetric studies were carried out by measuring weight change as function of time and mole fraction of NaCl in the reaction mixture. The different constituents in the reaction products were identified by X-ray diffraction analysis and the morphologies of the reaction products were discussed on the basis of metallography, scanning electron microscopy and energy dispersive X-ray analysis. The concentration of water soluble metal species was determined using atomic absorption spectrophotometry.
The transition metal carbides on interaction with NaCl are decomposed into respective metal oxides which further interact with NaCl forming sodium metal oxide and/or metal chloride depending upon the local conditions prevailing during the interaction. The solubility measurements indicate the formation of water soluble metal species.
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