Highly Selective Hydrodeoxygenation of Lignin to Naphthenes over Three-Dimensional Flower-like Ni₂P Derived from Hydrotalcite

Abstract

A strategy for low-temperature synthesis of hydrotalcite-based nickel phosphide catalysts (Ni2P-Al2O3) with flower-like porous structures was proposed. The in situ reduction of red phosphorus at 500 °C enables Ni2P catalysts with small particle size and abundant active and acidic sites, which facilitate the activation of substrates and H2. In the hydrodeoxygenation of guaiacol, a 100% conversion and 94.5% yield of cyclohexane were obtained over the Ni2P-Al2O3 catalyst under 5 MPa H2 at 250 °C for 3 h. Other lignin-derived phenolic compounds could also afford the corresponding alkanes with yields higher than 85%. Moreover, Ni2P-Al2O3 exhibited high hydrodeoxygenation activity in the deconstruction of more complex wood structures, including lignin oil and real lignin. Among the two different types of Ni sites of Ni(1) and Ni(2) in Ni2P, density functional theory (DFT) calculations showed that the Ni(2) site, highly exposed on the Ni2P-Al2O3 surface, possesses a stronger ability to break C–OH bonds during the hydrodeoxygenation of guaiacol in comparison with the Ni(1) site.

Catalytic Cleavage of the C–O Bond in Lignin and Lignin-Derived Aryl Ethers over Ni/AlPyOx Catalysts

“…Metal phosphates and phosphorus-doped materials had attracted the attention of researchers due to their excellent catalytic activity and unique physical and chemical properties. − Especially in application in biomass conversion, phosphorus-doped materials have been rapidly developed in recent years. − In this work, AlP y O x , prepared by calcinating a mixture of phytic acid and aluminum isopropoxide, was used to support Ni catalysts to catalyze the C–O bond cleavage of lignin model compounds under mild conditions. Benzyl phenyl ether, as a typical model compound of lignin, could be completely converted after reaction for 5 h with 3 MPa H 2 at 30 °C over the Ni/AlP 0.5 O x catalyst in this system.…”

Boosting Hydrolysis of Cellulose at High Temperature by β‐Glucosidase Induced Metal–Organic Framework In‐Situ Co‐Precipitation Encapsulation

“…To our knowledge, this flower-like structure material tended to be a multistage pore material, with a relatively large size and surface area. [38] It was noticeable that the β-G@MOF(PABA) was provided with a more complete flower-like structure, obvious wrinkle and pore structure at the petal edge compared with pure MOF(Figure 1 and Figure S4). It suggested that the induction of MOFs by enzymes can changed the morphology of enzyme complexes, firstly.…”

Integrated design of an amination process of lignin oxygenated model compounds to synthesize cyclohexylamine: catalyst nanostructure engineering and catalytic conditional strategy

“…The unique lignin structure is formed by various C-O and C-C bonds connected, such as α-O-4, β-O-4, and 4-O-5 bonds. [3][4][5][6][7][8][9][10][11][12] It is extremely challenging to realize lignin valorization. Extensive research studies have been performed on the selective cleavage of the high-strength and high-stability C-O bonds or C-C bonds of lignin via reductive depolymerization, oxidative depolymerization, pyrolysis, and other methods.…”