Gas phase dehydration of glycerol to acrolein on an amino siloxane-functionalized MCM-41 supported Wells–Dawson type H₆P₂W₁₈O₆₂ catalyst

Abstract

A novel amino siloxane-functionalized MCM-41 supported Wells–Dawson type H6P2W18O62 (D-HPW) catalyst was synthesized by a two-step method and investigated in the gas phase dehydration of glycerol to acrolein, and the yield of acrolein was obviously improved.

Nanosheet MFI Zeolites for Gas Phase Glycerol Dehydration to Acrolein

“…Besides acrolein and acetol, formaldehyde, acetaldehyde, acrylic acid, and allyl alcohol were also detected. Based on above results and former reports [9,23,27], the formation pathways of all detected products were shown in Scheme 1. Regarding product selectivity, NMZ-30 obtains the lowest acrolein selectivity in all NMZ-X samples (Figure 6b and Figure 8).…”

“…In recent years, a wide range of solid acid catalysts were employed for gas phase dehydration of glycerol to acrolein, such as transition metal oxides, heteropoly acids (HPAs), zeolitic catalysts, and so on [10,[13][14][15][16][17][18][19][20][21][22][23][24][25][26][27]. Among them, zeolites, like HZSM-5 [21], mordenite [28], ITQ-2 [7], etc.…”

Biomass valorisation over polyoxometalate-based catalysts

“…POMs supported on oxides (e.g. titania, 73 niobia, 74,75 alumina, 76,77 silica, alumosilicate, 78 and zirconium dioxide 77,79 ) and molecular sieves (MCM-41, 80 amino siloxane-functionalised MCM-41, 80,81 Zr-MCM-41, 82,83 SBA-15, 84 41 for the dehydration of glycerol to acrolein. The selectivity to acrolein increased with the increasing ratio of Brønsted to Lewis acids, while the lower ratio of Brønsted/Lewis acids favoured the production of hydroxyacetone as undesired side products.…”

Tuning of Selectivity for Sustainable Production of Acrolein from Glycerol

“…The mechanisms of acrolein and acetol formation on these sites were first proposed by Alhanash et al [16] who used Cs 2.5 H 0.5 PW 12 O 40 as a catalyst and then confirmed by many authors using metal oxides, [17,18] zeolites, [19,20] metal phosphides, [21] and HPAs. [22] In general, the dehydration of glycerol on Brønsted acid sites starts with the protonation of the secondary oxygen atom which has a higher negative charge compared to the terminal oxygen atoms (Scheme 3a). Then, the resulting protonated intermediate releases a hydronium to give 1,3-dihydroxypropene followed by its tautomerisation into 3-hydroxypropanal.…”