Synthesis of high sintering-resistant Ni-modified halloysite based catalysts containing La, Ce, and Co for dry reforming of methane

Dry Reforming of Methane over Rare-Earth Metal Oxide Ni–M–Al (M = Ce, La) Catalysts

“…Furthermore, the highest carbon formation was observed in 15Ni–15La–20Al, featuring, according to XRD, La­(OH) 3 not being stable during DRM. Analogously to the current case with the La-modified catalyst containing more carbon than the corresponding Ce-modified catalysts 15Ni–15Ce–20Al, the La-modified Ni–halloysite catalyst showed higher coking than Ce–Ni halloysite . In the current case, the Ce-modified catalyst exhibited a molar ratio of Ni/Ce of 1.35 (Table S1), while no coking was observed in ref with the spent Ni–Ce–alumina catalyst, with a Ni/Ce molar ratio of 1.6 and a nickel particle size of 10 nm after DRM at 800 °C.…”

“…For example, Ni supported on halloysite clay and promoted with Co, Ce, or La resulted in improved catalyst stability by suppressing metal sintering during DRM. 8 Ceria-promoted catalysts have been promising in DRM. An overview of different catalysts tested in DRM is demonstrated in Table S1.…”

“…On the other hand, especially supported nickel catalysts are prone to deactivation, which can be mitigated at least partially by fine-tuning the catalyst composition. For example, CeO 2 and La 2 O 3 have been intensively tested as promoters or supports for Ni, − ,− ,,, while other modifications involve the use of encapsulated Ni nanoparticles or mesoporous supports for Ni as well as modifications with iron . The main idea has been to suppress the sintering of Ni and coking with these methods.…”

“…The main idea has been to suppress the sintering of Ni and coking with these methods. For example, Ni supported on halloysite clay and promoted with Co, Ce, or La resulted in improved catalyst stability by suppressing metal sintering during DRM …”

Assessing the effect of acid and alkali treatment on a halloysite-based catalyst for dry reforming of methane

“…It has been demonstrated that the etching of silica in the outer layer of the halloysite causes some defects and cavities that can conne Ni particles, which, consequently, leads to the formation of a strong metal-support interaction. 18,66 The H 2 consumption is calculated for all the catalysts, and it ranges from 18 to 34 cm 3 per g STP (see Table 2). The highest H 2 Table 1 Textural properties of the Ni-doped HNTs, BET and pore size analysis…”