One-pot synthesis of a highly mesoporous Ni/MgAl₂O₄spinel catalyst for efficient steam methane reforming: influence of inert annealing

Abstract

The inert annealing step during the synthesis of the Ni/MgAl2O4 catalyst induces positive changes in the catalyst substructure. The obtained catalyst displayed high catalytic activity towards steam methane reforming with low carbon deposition.

Embedded Structure of Ni@PSi Catalysts for Steam Reforming of Methane

“…TGA analyses were performed to clarify the difference in carbon deposition performance of the spent catalysts as shown in Figure 6a. The weight loss below 200 °C was mainly from the absorbed water; the increased weight in the temperature ranges from 200 to 400 °C was attributed to the oxidation of metallic Ni species [26] . The weight loss stage exceeding 400 to 700 °C was due to the oxidation of the deposited carbon species formed in SRM [26,32] .…”

“…Ni@PSi‐850 catalyst had the lowest S BET because of the destroyed layered structure as confirmed by FT‐IR measurement (Figure 1b). All Ni@PSi‐x catalysts showed obvious H3 hysteresis loops and IV curves, indicating the mesoporous structure (Figure S1) [23,26] …”

“…All Ni@PSi-x catalysts showed obvious H3 hysteresis loops and IV curves, indicating the mesoporous structure (Figure S1). [23,26] TEM micrographs of fresh Ni@PSi samples reduced at different reduction temperatures were presented in Figure 2. The characteristic layered structure of Ni-containing phyllosilicate was clearly observed in the as-prepared Ni-PSi precursor (Figure 2a).…”

“…The weight loss below 200 °C was mainly from the absorbed water; the increased weight in the temperature ranges from 200 to 400 °C was attributed to the oxidation of metallic Ni species. [26] The weight loss stage exceeding 400 to 700 °C was due to the oxidation of the deposited carbon species formed in SRM. [26,32] Ni@PSi-600 had the minimum weight loss, which was benefit from the well-confined Ni NPs by the embedded structure.…”

“…[26] The weight loss stage exceeding 400 to 700 °C was due to the oxidation of the deposited carbon species formed in SRM. [26,32] Ni@PSi-600 had the minimum weight loss, which was benefit from the well-confined Ni NPs by the embedded structure. Raman spectroscopy was further used to identify the type of coke as shown in Figure 6b.…”