2D Polymeric Network of Cu/Na, A Route for the Preparation Truncated Octahedral Catalyst Applicable in the WGS Reaction

Abstract

A 2D heterometallic copper(II)–sodium(I) complex based on pyridine 2,6-dicarboxylato (dipic2-) formulated as [Cu(μ-dipic)2{Na2(µ-H2O)4}]n. 2nH2O (1) has been synthesized. Thermal stability of complex 1 was studied by thermo gravimetric analysis (TGA) and differential thermal analysis (DTA). Single-crystal X-ray diffraction (SC-XRD) analysis showed that the parallelepiped colorless crystal of complex 1 crystallizes in a monoclinic system with the space group P2/c . A highly dispersed truncated octahedral catalyst formulated as Cu-Na/Al2O3 (CNM) was prepared by thermal decomposition of complex 1. Besides, the reference catalyst of Cu-Na/Al2O3 (CNR) was prepared by impregnation conventional method. The catalysts were examined by FT-IR, powder X-ray diffraction (XRD), scanning electron microscopy (SEM), Brunauer–Emmett–Teller (BET) surface area, and subjected to water-gas shift (WGS) reaction in the temperature range of 150-400 °C. The catalysts showed strong surface structure-activity dependence in WGS reaction. Improved catalytic performance during the water-gas shift reaction was observed for CNM compared to CNR due to its high dispersion, smaller particle size, and higher BET specific surface area.