Transformation of non-edible vegetable oils into biodiesel fuels catalyzed by unconventional sulfonic acid-functionalized SBA-15

Abstract

A real understanding of intrinsic acidity and catalytic property of unconventional and sulfonic acid-functionalized SBA-15 platelet catalysts synthesized with the aid of highly solvated Zr 4+ salts (shortly termed SA-SBA-15-p) for transesterification of non-edible vegetable oils into biodiesel fuel (BDF) was reported, in comparison with conventional SBA-15 catalyst (shortly termed SBA-15-conv), unconventional SBA-15 platelet catalyst (shortly termed SBA-15-p) and commercial sulfonic resins of Amberlyst-15 and SAC-13. Thorough characterizations and catalytic study revealed that the content of fatty acid methyl ester (FAME) as the main component of BDF was increased in the order of SBA-15-conv < SAC-13 < SBA-15-p < Amberlyst-15 < 5-25SA-SBA-15-p, which correlated closely with the loading, distribution, strength of acidic sites. Among them, the unconventional 15SA-SBA-15-p catalyst with proper loadings of propylsulfonic groups (1.15 mmol S -1 g -1 ) and superficial Zr 4+ clusters (0.66 mmol g -1 ) as a mixed solid Bronsted and Lewis acid, which had differential heat of NH 3 adsorption in the range of 90-125 kJ mol -1 , gave highest FAME content with low concentrations of byproducts, such as glycerides and free fatty acid (FFA). In addition to high water and FFA tolerance levels, the used 15SA-SBA-15-p catalyst could be easily regenerated by ethanol extraction and its high activity was maintain. By contrast, 3 the SBA-15-conv catalyst without any Lewis and Bronsted acids had almost no activity in BDF synthesis. The unconventional SBA-15-p catalyst with superficial Zr 4+ clusters as a pure solid Lewis acid gave a moderate FAME content accompanying with a high concentration of unreactive glycerides. Commercial sulfonic resins of Amberlyst-15 and SAC-13 with strongly phenylsulfonic and Nafion sulfonic groups as pure solid Bronsted acids gave moderate FAME contents accompanying with high concentrations of unreactive glycerides and unwanted FFA byproducts. Furthermore, they were significantly deactivated by water, FFA and regeneration treatment due to the poison and leaching of sulfonic groups and the decomposition of thermally unstable framework.Keywords: mesoporous silica materials, solid Lewis and Bronsted acids, crude and non-edible vegetable oils, the water and FFA tolerance levels, reusability.

Co-Processing of Jatropha-Derived Bio-Oil with Petroleum Distillates over Mesoporous CoMo and NiMo Sulfide Catalysts

“…High-resolution transmission electron microscopy (HRTEM) images were also obtained. In the in situ DRIFT spectra with pyridine adsorption (Figure 3A), the characteristic DRIFT signals centered at 1442 and 1540 cm −1 are assigned to pyridine adsorbed on Lewis and Bronsted acid sites, respectively [18][19][20]. The DRIFT signal centered at 1442 cm −1 is stronger than others, indicating that mesoporous sulfide catalysts are mostly related to Lewis solid acids.…”

“…A modified recipe for the preparation of mesoporous sulfide catalysts, which would be suitable for upgrading Jatropha bio-oil co-fed with petroleum distillates, was developed from our previous studies on hydrotreating catalysts for the conventional diesel HDS process [17][18][19]. A commercial support of γ-Al2O3 was kindly provided by a Japanese catalyst company.…”

Screening of mono- and bi-functional catalysts for the one-pot conversion of cellobiose into sorbitol

“…Therefore, the choice of the solid acid for the preparation of a bi-functional catalyst is very important. Ideally, the solid acid should not only be able to catalyze the hydrolysis of the substrate but also ought to be very stable under reaction conditions; otherwise, the leaching of the acid sites would result in a decrease of activity in the hydrolysis [10,20,[23][24][25][26]. Furthermore, the leaching of the acid sites can increase the rate of the metal leaching which is further detrimental.…”

Current advances in the utility of functionalized SBA mesoporous silica for developing encapsulated nanocatalysts: state of the art

“…Mesoporous silica materials [14][15][16][17][18][19][20] have not only proved their utilities as heterogeneous catalysts [21][22][23][24][25][26][27][28][29] for promoting various organic transformations, [30][31][32][33][34][35][36][37] but also nd interesting applications 38,39 in other research elds such as food chemistry, 40 production of bio-mass derived chemicals, [41][42][43][44][45] petrochemisry, 46-48 sensors, waste treatment, 49,50 optical materials and carriers. One of the most important advances in this eld is developing hybrid systems through functionalization of mesoporous silica materials.…”