Preparation of Mn substituted La-hexaaluminate catalysts by using supercritical drying

Synthesis of the high-surface-area CexBa1−xMnAl11Oycatalyst in reverse microemulsions using inexpensive inorganic salts as precursors

“…The supercritical drying process was operated at 260 uC and 7.0-8.0 MPa for 2 h. The details of the drying method were described elsewhere. 8 The precursor was calcined at 800, 1000, 1100 and 1200 uC in a muffle in air for 5 h, respectively. The precursor dried by the SCD method was designated as aerogel.…”

“…At the low temperatures, the combustion reaction is mainly controlled by surface reaction. 8 Compared with the CD catalyst, the SCD catalyst has higher surface area; and the SCD catalyst could provide larger reacting surface. T 90 (the temperature at 90% methane conversion) over the SCD catalyst is 770 uC, lower than those over the CD one (810 uC).…”

“…At the high temperatures, the combustion reaction of methane is mainly controlled by mass transfer process. 8 The high surface area of the SCD catalyst favors gas diffusivity. Therefore, the SCD catalyst shows higher activity than the CD one.…”

Morphology transcription process from CMC micelles to inorganogel and its effect on the properties of alumina particle

“…The washed cake was put into an autoclave and dried under supercritical ethanol condition (260 • C, 8.0 MPa). The details of the supercritical drying method were illustrated elsewhere [13]. Finally, the dried aerogel was calcined in air at 1200 • C for 4 h. The precursor and the calcined alumina samples were designated as Aerogel CMC and Al CMC , respectively.…”

Catalyzed Ceramic Burner Material

“…Thermal sintering and subsequent loss of surface area is also of concern, and hexaaluminates are widely regarded as one of the best material systems for providing resistance toward thermal sintering at elevated temperatures (Svensson, Boutonnet, & Jaras, 2008). The challenge with hexaaluminates continues to be the low inherent surface areas and activity, and significant efforts are focused on new synthetic methods to generate higher surface area hexaaluminates without compromising the properties of high thermal stability (Bai, 2009;Wang, 2003;Zhai & Li, 2006;Xu, 2003).…”