Effect of sol–gel synthesis parameters and Cu loading on the physicochemical properties of a new SUZ-4 zeolite

SUZ-4 zeolites were synthesized hydrothermally using bagasse ash (BA) as a co-silica source and tetraethlyammonium hydroxide as a template, with synthesis occurring at a SiO2:Al2O3 ratio of 21.2 under autogenous pressure. Different amounts of copper (II) were loaded in the K+/SUZ-4 with different weight percentages: 2.3, 2.8, 3.3 and 5.5. The physico-chemical characterization of the obtained SUZ-4 and Cu-loaded SUZ-4 were investigated using X-ray powder diffraction (XRD), scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM/EDS), X-ray fluorescence (XRF), BET-N2 adsorption, and Fourier transform infrared spectroscopy (FTIR). The results show that Cu loading did not change the structure of SUZ-4. The obtained SUZ-4 zeolite has a narrow pore size distribution and a needle-shaped crystal with approximately 0.07 μm mean diameter. The increase in BA content did, however, change the total pore volume and BET surface area, due to the competitive formation of merlinoite zeolite (MER), phillipsite (PHI) and Linde Type F during the crystallization process.