Zr-modified hierarchical mordenite as heterogeneous catalyst for glycerol esterification

Abstract

Hierarchical mordenite catalysts were prepared by HF and NH4F etching. Materials' zirconia modification was performed by incipient wetness impregnation in order to vary surface acidity type and strength. XRD, N2 physisorption, solid-state NMR and UV-Vis spectroscopies were applied for characterization. Acidic properties of the obtained materials were investigated by TPD of adsorbed ammonia and FT-IR spectra of adsorbed pyridine. Catalytic performance was studied for the glycerol esterification with acetic acid. Zr increased reaction turnover activity compared to raw zeolite substrate due to abundant Brönsted and Lewis moiety presence. The demonstrated biomass valorization processes to bio-based platform chemicals are of interest, as they employ biodiesel production waste.11

Advances in porous and nanoscale catalysts for viable biomass conversion

“…Zr-modified hierarchical mordenite catalysts, prepared by HF and NH 4 F etching, followed by incipient wetness impregnation, are useful catalysts for the glycerol esterification with acetic acid to produce biodiesel additives. 162 The addition of Zr led to improved turnover activity compared to pure zeolite, due to the presence of well-balanced Brønsted-Lewis acid sites.…”

State of the Art and Perspectives of Hierarchical Zeolites: Practical Overview of Synthesis Methods and Use in Catalysis

“…The treated mordenites were subsequently tested in the DME carbonylation to methylacetate. [257] Next to HNO 3 that was used in previous studies, there exist other mineral acids that can be employed as well for the dealumination of mordenites, such as HF [259,260] and NH 4 F, [259] but also organic acids like oxalic acid [255] and citric acid [261] can be used. However, the effect of these acids on for instance the increase in mesopore volume was not as pronounced as was the case with HNO 3 .…”

Catalytic Cracking of Biodiesel Waste Using Metal Supported SBA-15 Mesoporous Catalysts

“…However, glycerol can also be converted to valuable products as hydrocarbon molecules and synthesis gas [3][4][5][6][7]. Techniques used for the transformation of glycerol include hydrogenolysis [8][9][10][11][12], dehydration [13][14][15][16], esterification [17,18], carboxylation [19], catalytic cracking [20,21], and other reactions [22,23]. Pyrolysis can transform biodiesel waste to more useful chemicals, but it exhibits low conversion level and selectivity.…”