A novel synthesis process of ETS-4 titanosilicate using commercial anatase in the absence of fluoride ions

A novel synthesis process for ETS-4 titanosilicate using commercial anatase as the titanium source in the absence of fluoride ions was studied. Fluoride ions and traced ETS-4 seeds have important roles in forming ETS-4 structures. However, the method using ETS-4 seeds instead of fluoride ions to improve product purity and productivity is environment-friendly. ETS-4, ETS-4(NS), and ETS-4(NaF) were respectively synthesized using traced ETS-4 seeds, without seeds, and with fluoride ions. The as-synthesized samples were identified by X-ray diffraction, scanning electron microscopy, and thermogravimetric analysis. Adsorption isotherms and adsorption heats of nitrogen and methane on the prepared ETS-4 were also measured. The results showed that ETS-4 samples could be prepared using anatase in the absence of fluoride ions, with good purity, comparable physicochemical properties, and excellent adsorption properties.