Environmentally friendly efficient coupling of n-heptane by sulfated tri-component metal oxides in slurry bubble column reactor

SO4−2/SnO2–catalyzed cyclocondensation for the synthesis of fully functionalized pyridines

“…[13] In recent years, several rules and legislations are made on environmental emission, considering that efficient catalytical methods are much desirable. [16][17][18][19] Sulfated tin oxide (STO) is used as a heterogeneous catalyst for the last few years because of its large surface area. [14,15] Sulfated metal oxides were used as solid super-acid catalysts since they had Lewis and Brønsted acid sites, and they were also nontoxic, atmospherically stable, and thermally stable in nature.…”

A New Deactivation Mechanism of Sulfate-Promoted Iron Oxide

“…Among the solid acids, the sulfate-promoted metal oxides have been attracting more and more attention in recent years [1][2][3][4][5][6][7] due to their unique advantages over those traditional liquid acid catalysts. For example, they are quite stable to moisture, air, and heat, and they are also less corrosive to reactors and containers, and they are also environmentally friendly [8][9][10][11][12][13]. Above all, they exhibit extremely high initial activities in catalyzing many organic reactions such as esterification, isomerization of n-alkanes, cracking reaction, and so forth, even at very mild conditions [2][3][4][5][9][10][11][12][13].…”

“…For example, they are quite stable to moisture, air, and heat, and they are also less corrosive to reactors and containers, and they are also environmentally friendly [8][9][10][11][12][13]. Above all, they exhibit extremely high initial activities in catalyzing many organic reactions such as esterification, isomerization of n-alkanes, cracking reaction, and so forth, even at very mild conditions [2][3][4][5][9][10][11][12][13]. However, there is a fatal problem for people to utilize them as practical catalysts in chemical industry to replace those liquid acid catalysts with them.…”

SO<sub>4</sub><sup>2-</sup>/SnO<sub>2</sub>-Catalyzed C3-alkylation of 4-hydroxycoumarin with secondary benzyl alcohols and <i>O</i>-alkylation with <i>O</i>-acetyl compounds

“…Sulfated metal oxides with both Brønsted and Lewis acid sites are widely used as solid super acid catalysts [34,35]. Sulfated metal oxides are stable to moisture, air and heat [36]. They are easy to prepare and environmentally benign [37].…”