Effect of Cu promoter on polyvinyl alcohol-assisted preparation of iron catalyst for Fischer-Tropsch synthesis

Fe₂O₃ or FeCu catalysts were prepared by co-precipitation method with or without the assistance of polyvinyl alcohol (PVA). The effect of Cu promoter on the structure and catalytic behaviour of the catalysts were investigated. The catalysts were characterized by BET, SEM, XRD, H₂-TPR and FT-IR techniques. The results showed that the addition of Cu promoter could enhance the crystal growth of α-Fe₂O₃, decrease BET surface area and pore volume and increase pore size and promote the reduction of the catalysts in H₂. In addition, Cu promoter remarkably influenced the surface morphology. In Fischer-Tropsch synthesis (FTS) reaction, the catalytic activity was increased when Cu promoter was added only. The addition of Cu promoter and PVA decreased the FTS activity, and shifted the hydrocarbon products to lighter molecular weight.