Christensen Paul A, Mashhadani Z T A W, Md Ali Abd Halim Bin, Carroll Michael A, Martin Philip A
School of Engineering , Newcastle University , Bedson Building , Newcastle upon Tyne , U.K. , NE1 7RU.
School of Natural and Environmental Sciences , Newcastle University , Bedson Building , Newcastle upon Tyne , U.K. , NE1 7RU.
J Phys Chem A. 2018 May 3;122(17):4273-4284. doi: 10.1021/acs.jpca.7b12297. Epub 2018 Apr 23.
This paper reports in situ Fourier transform infrared (FTIR) spectroscopic studies on the nonthermal plasma reaction of isopropyl alcohol in dinitrogen at Macor (a ceramic containing oxides of Al, Mg, and Si) and the analogous thermally driven process. While isopropyl alcohol did not react at the Macor at temperatures up to 600 °C, the study of the nonthermal plasma-driven process at the ceramic led to unexpected chemistry hitherto not observed, primarily the reaction of IPA in dinitrogen at short time scales to produce methane, HCN, acetone and "cold" CO at ca. 115 K. The CO, methane, and HCN rapidly established steady state concentrations, pointing to the need for faster FTIR studies: at longer times, isophorone and a "polymethylacetylene-like" polymer were formed as a brown oil. The observation of the steady-state gases and brown oil suggested parallel pathways in the plasma, the latter taking place at the plasma/catalyst interface, and the former in the plasma remote from the catalyst. Replacing dinitrogen with argon completely inhibited or negated the production of the oil, had no effect upon the processes taking place in the plasma remote from the Macor, and instead resulted in the production of acetylene.
