Direct high-pressure gas-phase oxidation of natural gas to methanol and other oxygenates

Abstract

PACS. 75.25+z -Spin arrangements in magnetically ordered materials (including neutron and spin-polarized electron studies, synchrotron-source X-ray scattering, etc.). PACS. 75.30Kz -Magnetic phase boundaries (including magnetic transitions, metamagnetism, etc.). PACS. 75.50Pp -Magnetic semiconductors.Abstract. -We studied magnetic order in EuTe by neutron diffraction under applied pressures up to 17 GPa. In the range P < 11GPa, the original antiferromagnetic (AF) phase with a propagation vector k = 1/2 1/2 1/2 transforms into another AF one with k = 1/4 1/4 1/4, then into a ferromagnetic phase. The observed sequence of magnetic transitions qualitatively confirms the proposed models of competing ferromagnetic and antiferromagnetic interactions in the EuX family (X = O, S, Se, Te). Nevertheless, a quantitative analysis of our data shows some differences with microscopic models. The structural transition from NaCl to CsCl phase occurs between 13 and 17 GPa. Interestingly, we do not observe any long-range magnetic order in the high-pressure CsCl phase.

High-pressure oxidation of methane

“…11. In line with findings of earlier studies[1,[90][91][92], reactions of methylperoxyl radicals are found to be important. The methane oxidation rate and even more so the formation of methanol and formaldehyde are sensitive to the reactions of CH 3 OO with both stable species (CH 2 O, CH 4 ) and radicals (HO 2 and CH 3 ).…”

“…Prediction of the methanol yield is also sensitive to reactions of the methylperoxyl radicals with CH 2 O (R35), CH 4 (R34), HO 2 (R30), and CH 3 (R31), in agreement with the results of Arutyunov et al[90]. These reactions also show up in the sensitivity analysis for formaldehyde.…”

Methane conversion using a high‐frequency pulsed plasma: Discharge features

“…Direct methane conversion to more valuable chemicals and liquid fuels has attracted much more attention from the beginning of 1980s (Edwards and Foster, 1986;Spencer and Pereira, 1987;Renesme et al, 1992;Fierro, 1993;Fox, 1993;Krylov, 1993;Parkyns et al, 1993;Arutyunov et al, 1996). Catalytic selective oxidation of methane to methanol was expected to be able to obviously save investment and operation cost if methane conversion and methanol selectivity can reach high levels.…”

Ab Initio Study for Selective Oxidation of Methane with NOx(x= 1, 2)

“…As far as we are aware, there is little experimental information on a detailed reaction mechanism for the conversion of methane to C 1 -oxygenates with NO because of the difficulty of the analysis of the rapid consecutive radical chain reactions. A theoretical investigation has also not yet been conducted because this reaction system has many plausible pathways formed by a large number of elementary reactions with O 2 . , …”