Surfactant-assisted preparation of FeCu catalyst for Fischer-Tropsch synthesis

Abstract

FeCu catalysts were prepared by co-precipitation method with or without the assistance of the surfactant, polyvinyl pyrrolidone (PVP), polyvinyl alcohol (PVA) or polyethylene glycol (PEG). The effect of surfactant on the structure and catalytic behavior of FeCu catalysts was investigated. The catalysts were characterized by inductively coupled plasma (ICP) spectroscopy, Brunauer- Emmett-Teller (BET) surface area, scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), H2-temperature-programmed reduction (TPR) and Fourier transform infrared (FTIR) spectroscopy techniques. They were tested for Fischer-Tropsch synthesis (FTS) at 230-310°C. The results showed that the catalysts prepared with PVA were more active than the catalysts prepared without any surfactant's assistance, the catalysts prepared with PVP and the catalysts prepared with PEG. In addition, the morphologies of the iron catalysts can be controlled by different surfactants. Meanwhile, addition of surfactant remarkably influenced the growth orientation of hematite nanocrystals, resulting in preferential exposure of the (110) plane. The characterization results revealed that PVA can promote the dispersion of iron oxides and the formation of the more active phase on the catalyst.