AbstractsChemistry

Pyrolysis Studies of Copper and Copper Phosphate Mixtures on a Tungsten Surface

by Kharel Aryashree Poudyal




Institution: Southern Illinois University at Edwardsville
Department:
Year: 2016
Keywords: Chemistry
Posted: 02/05/2017
Record ID: 2126630
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Abstract

The purpose of this research is to identify the chemical species present on a tungsten filament atomizer in the moment prior to the atomization. The first sample prepared was used to investigate the effects of copper samples with phosphate modifier and the second sample investigated the effect of copper samples with pyrophosphate. The aim of this thesis is to investigate the thermal decomposition of copper phosphate on a tungsten surface. An alumina crucible was used to understand the role of tungsten. The project sought to identify the possible copper compounds that remain after drying and pyrolysis in electrothermal atomic absorption spectroscopy. This was carried out by examining the effect of mass loss with the time and temperature. Dry sample residues, prior to and following heating, were studied using thermogravimetric analysis (TGA). X-ray diffraction showed that the starting material before performing TGA analysis was copper phosphate hydrate. The observation showed the formation of copper pyrophosphate at around 600°C for different concentrations of sample prepared. The X-ray diffraction (X-RD) spectra from TGA confirmed the formation of crystalline copper pyrophosphate at around 600 °C. The well separated endo thermal effects correlate to the mass loss steps and characterize thermal behavior of copper pyrophosphate.