Synthesis of Ni-Al layered double hydroxide via coprecipitation: Formation mechanism, synthesis intensification, and catalytic application

Herein, the formation mechanism of Ni-Al layered double hydroxide (NiAl-LDH) synthesized by coprecipitation was explored. Moreover, NiAl-LDH was prepared in a rotating packed bed (RPB) under different rotation speeds, which shows that increasing the rotation speed decreases the lateral size and thickness of NiAl-LDH, since high rotation speed accelerates the nucleation of NiAl-LDH. Additionally, the Ni/mixed metal oxides (MMO) catalysts derived from NiAl-LDH were prepared for maleic anhydride (MA) hydrogenation. Result shows that Ni/MMO catalyst obtained from NiAl-LDH prepared under a higher rotation speed exhibits higher MA conversion due to its larger surface area and smaller nickel particle size. The Ni/MMO catalyst obtained from NiAl-LDH prepared under 500 rpm exhibits 100% MA conversion and 100% succinic anhydride selectivity under 30 & DEG;C and 2 MPa within 1 h. This work provides fundamental insight to understand the formation of NiAl-LDH. Moreover, RPB as an effective technique to synthesize NiAl-LDH and Ni-based catalysts was validated.

Automated summary

This study explores the formation mechanism of Ni-Al layered double hydroxide (NiAl-LDH) synthesized by coprecipitation. Furthermore, NiAl-LDH is prepared in a rotating packed bed (RPB) under different rotation speeds, and results show that increasing the rotation speed decreases the lateral size and thickness of NiAl-LDH due to accelerated nucleation. Additionally, the Ni/mixed metal oxides (MMO) catalysts derived from NiAl-LDH exhibit higher MA conversion with larger surface area and smaller nickel particle size.