Salt-assisted surface charge driven synthesis of large pores alumina as carbon tolerance support for propane dehydrogenation

Yu Zhang; Wen-Cui Li; Xin-Qian Gao; Shu-Zhen Zhou; Zhankai Liu; Hao-Wei Wang; An-Hui Lu

doi:10.1016/j.jcis.2023.05.144

Salt-assisted surface charge driven synthesis of large pores alumina as carbon tolerance support for propane dehydrogenation

J Colloid Interface Sci. 2023 Oct 15:648:169-180. doi: 10.1016/j.jcis.2023.05.144. Epub 2023 May 24.

Authors

Yu Zhang¹, Wen-Cui Li¹, Xin-Qian Gao¹, Shu-Zhen Zhou¹, Zhankai Liu¹, Hao-Wei Wang¹, An-Hui Lu²

Affiliations

¹ State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, Liaoning, China.
² State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, Liaoning, China. Electronic address: anhuilu@dlut.edu.cn.

PMID: 37301142
DOI: 10.1016/j.jcis.2023.05.144

Abstract

Porous alumina has been widely used as catalytic support for industrial processes. Under carbon emission constraints, developing a low-carbon porous aluminum oxide synthesis method is a long-standing challenge for low-carbon technology. Herein, we report a method involving the only use of elements of the aluminum-containing reactants (e.g. sodium aluminate and aluminum chloride), sodium chloride was introduced as the coagulation electrolyte to adjust the precipitation process. Noticeably, the adjustment of the dosages of NaCl would allow us to tailor the textural properties and surface acidity with a volcanic-type change of the assembled alumina coiled plates. As a result, porous alumina with a specific surface area of 412 m²/g, large pore volume of 1.96 cm³/g, and concentrated pore size distribution at 30 nm was obtained. The function of salt on boehmite colloidal nanoparticles was proven by colloid model calculation, dynamic light scattering, and scanning/transmission electron microscopy. Afterward, the synthesized alumina was loaded with PtSn to prepare catalysts for the propane dehydrogenation reaction. The obtained catalysts were active but showed different deactivation behavior that was related to the coke resistance capability of the support. We figure out the correlation between pore structure and the activity of the PtSn catalysts associated with the maximum conversion of 53 % and minimum deactivation constant occurring at the pore diameter around 30 nm of the porous alumina. This work offers new insight into the synthesis of porous alumina.

Keywords: Macroporous alumina; Precipitation; Propane dehydrogenation; Salt.