Complete oxidation of methane on supported palladium catalyst: Support effect

Catalytic behavior and reaction routes of MEK oxidation over Pd/ZSM-5 and Pd–Ce/ZSM-5 catalysts

“…One of the main factors is likely to be the acidity. Pd loaded on an acidic support is reportedly more effective in catalyzing an oxidization reaction than when it is loaded on neutral or basic supports because the electrophilic character of acidic supports results in an electron deficiency in Pd atoms [31,32]. In addition, it was also determined that the PCZ catalyst with more acid sites (especially the strong acid sites) has a higher catalytic activity.…”

Synthesis and characterization of Pd/ZSM-5/MCM-48 biporous catalysts with superior activity for benzene oxidation

“…For instance, Pd/MCM-48 possesses a relatively low Pd dispersion (D c = 2.33 nm) although it possesses a large specific surface area (Tables 1 and 2). Muto et al and Okumura et al [11,13,15] reported that the support acid property plays an important role in VOCs catalytic activity, because the acid sites can determine the Pd dispersion on the support. Similarly, in our previous work, we also found that Pd atoms are inclined to disperse on the support with a larger surface area and more acid sites (especially the strong acid sites) [58].…”

“…In addition, the specific surface area of Pd/ZSM-5 (326.4 m 2 /g) is also smaller than that of Pd/MCM-48 (1029 m 2 /g) ( Table 2). Many researchers reported that Pd particles loaded on acidic supports were more easily oxidized than those supported on the neutral or basic support as the acidic supports with elec- trophilic character resulted in the electron deficiency on Pd atoms [11,13,15], and the acceleration of Pd 0 → Pd 2+ can also promote the catalytic reaction according to the Mars-van Krevelen model (the second step). As a consequence, we expect that the acidity and Pd dispersion may have a synergetic effect on benzene catalytic oxidation, as the acidity of Pd/ZSM-5 (0.41 mmol NH 3 /g-cat.)…”

“…On the other hand, researchers have found that the catalyst support plays an important role in the generation of active species and in the catalytic performance for the Pd-loaded catalysts [11,12]. For instance, Niwa and co-workers [13] proposed that the activity of Pd-based catalysts was very much dependent on the acid-base character of the supports. They further demonstrated that the Brønsted acid sites were responsible for the generation of dispersed Pd species, and that the acid-base property of the support can significantly influence the dispersion and oxidation state of Pd [11,14,15].…”

High-throughput screening of coke resistant catalyst with thermal barcode

“…Catalyst supports influence catalytic reaction via the support structure and metal and support interaction. 80 When the support is microporous structure (< 2nm), the pore is too small for the coke molecule to go inside. Porous silica with a small pore size of 2 nm was taken into study.…”