Selective oxidation of n-butane in the presence of vanadyl pyrophosphates synthesized by intercalation–exfoliation–reduction of layered VOPO4·2H2O in 2-butanol

Partial Oxidation of n-Butane over a Sol-Gel Prepared Vanadium Phosphorous Oxide

“…A similar shape but larger size, 1000 nm, is observed for active phase from MS and HS precursors. The crystallite thickness was estimated from both the Scherer's equation [29] and the surface area [17]. The XRD-based calculation yielded 14 nm for those having 600 nm in length and 11 nm for those of 1000 nm; the estimation from the surface area measurements gave values of 4 and 7 nm respectively.…”

“…The size of the crystallite has been demonstrated to affect the catalytic activity of VPO. Small crystallites of the precursor yielded small crystallites of the active phase and were reported as highly selective for the partial oxidation of butane to maleic anhydride [16][17][18]. Those small active crystallites are thought to form when the precursor crystallites break apart [19].…”

“…An exfoliated-reduced precursor in 1-butanol yielded an active phase with 3000 nm crystallite size that gave 53% selectivity to maleic anhydride at a conversion of 50% at 430 °C [7]. When 2-butanol was used as the exfoliating-reducing agent, the active phase with 800 nm crystallites was 75% selective at 50% conversion at 390 °C [16,17,19]. Finally, when the materials were exfoliated with a mixture of 2-butanol and ethanol, the active phase with 50 nm crystallites was 82% selective at 50% conversion at 390 °C [18].…”

Structural Characteristics, Stability, and Activity of (VO)2P2O7 and VO(PO3)2 Catalysts in p‐Cymene Liquid‐Phase Oxidation

“…[6][7][8][9][10][11][12][13][14] The catalytic performance of both VO(PO 3 ) 2 and (VO) 2 P 2 O 7 catalysts have been evaluated in gas-phase reactions such as oxidations, oxidative dehydrogenations, and ammoxidations. [15][16][17][18][19][20][21][22][23] However, VO(PO 3 ) 2 showed poor catalytic performance in gas-phase oxidation of n-butane to maleic anhydride when compared to the high catalytic activity of (VO) 2 P 2 O 7 . The poor catalytic performance of VO(PO 3 ) 2 in n-butane oxidation, due to low activity and selectivity, has limited its application in other chemical reactions.…”

Intercalação de íons lantanídeos e de poli(óxido de etileno) assistida por tensoativo na matriz hospedeira VOPO4.2H2O

“…Como já discutido anteriormente, a literatura apresenta uma discordância quanto à morfologia da matriz VOPO 4 .2H 2 O. Um grupo de artigos apresenta uma morfologia quadrada de tamanho médio dos cristais entorno de 10µm[28,57,58], enquanto um segundo grupo reporta cristais arredondados com circunferência média de 10µm[18,59]. e espessura de 0,8µm aproximadamente; ou seja; ocorreu uma diminuição do tamanho desses cristais quando comparada com a matriz VOPO 4 .2H 2 O sintetizada de acordo com a literatura[9].…”