Fluidized bed processing of sodium tungsten manganese catalysts for the oxidative coupling of methane

Magnetic Properties of Reduced and Reoxidized Mn–Na2WO4/SiO2: A Catalyst for Oxidative Coupling of Methane (OCM)

“…The catalysts were synthesized following procedures similar to those described previously in detail elsewhere allowing for production of large catalysts amounts and yielding comparable catalytic activity to catalysts prepared with incipient wetness impregnation method. 11 In this study, the SiO 2 support (Davisil 636, Sigma Aldrich, particle size 150-350 μm) was coated with 5 min and subsequently exposed to 1 mL of 30 % CH 4 in He. A total flow of 30 mL/min was used for an inner reactor diameter of 8 mm, a height of the catalyst bed of approx.…”

Data Driven Determination of Reaction Conditions in Oxidative Coupling of Methane via Machine Learning

“…In order to develop the OCM catalysts with these functions, hundreds of inorganic materials have been investigated as summarized in the previous review articles . Among the reported catalysts, Mn‐Na 2 WO 4 /SiO 2 exhibits relatively high activity, selectivity, and stability for the OCM . The catalytic performance of Mn‐Na 2 WO 4 /SiO 2 has been further improved by meso‐ordered structure of SiO 2 support as well as by a membrane reactor with separated feeding of CH 4 and O 2 .…”

“…[20,21] Among the reported catalysts, Mn-Na 2 WO 4 /SiO 2 exhibits relatively high activity, selectivity, and stability for the OCM. [23][24][25][26] The catalytic performance of Mn-Na 2 WO 4 /SiO 2 has been further improved by meso-ordered structure of SiO 2 support as well as by a membrane reactor with separated feeding of CH 4 and O 2 . [27,28] However, no catalytic reaction systems affording sufficient C 2 yield and selectivity for practical large-scale application have been developed.…”

Characterization of Mn–Na2WO4/SiO2 and Mn–Na2WO4/MgO catalysts for the oxidative coupling of methane

“…Mn, Na and W, on the catalytic activity and selectivity [5][6][7][8][9][10], the effects of reaction pressure [11] and temperature plus CH 4 :O 2 ratio [12], and studies have been conducted to investigate support materials other than SiO 2 [13][14][15][16]. In addition, fluidized bed processing for large scale production has been tested using the Mn-Na 2 WO 4 /SiO 2 catalyst [17][18]. A welldocumented phenomenon associated with the Mn-Na 2 WO 4 /SiO 2 catalysts is the phase transformation of the silica support from amorphous silica to the highly crystalline -cristobalite phase after calcinations at 800 °C, a phase transition that does not occur until higher temperatures when impregnating a silica support with manganese or sodium alone [1,5,6,10].…”