Major Project

High performance Cu–ZnO/Pd-b catalysts for syngas to LPG

Qingjie et al. (2008) conducted a performance study of Cu (Copper)/ZnO (Zinc oxide) over Pd (Palladium)-b (beta-zeolite) for preparation by physically mixing. They investigated Cu-ZnO/Pd-b zeolite because Cu strongly inhibits coke formation, ZnO was helped dispersion of Cu in catalyst, Pd-b was showed the best activity for conversion methanol to LPG. In this research, they studied different kinds of zeolites, influence of SiO₂/Al₂O₃ ratio, crystal size b of catalyst, influence of Pd content on catalyst, and optimum condition for synthesis LPG from syngas. After preparation,  the catalyst will analyzed by X-ray Diffraction (XRD) for the study crystal size of catalyst, Scanning Electron Microscope (SEM) for looking crystal of catalyst, and H₂-chemisorption. From the results found that Cu-ZnO/Pd-b was higher conversed methanol to LPG than Cu-ZnO/Pd-ZSM-5, and Cu-ZnO/Pd-UDY due to Cu-ZnO/Pd-b showed the high activity by CO conversion achieve 72.9%.  The SiO₂/Al₂O₃ ratio at 37 was showed high CO conversion because acidic active site of catalyst increasing by CO conversion achieve 72.2%. The crystal size b at (2) was showed high CO conversion because this size have small crystal size. The Pd content at 0.2 wt% was showed high CO conversion. For optimum condition at the study found that at temperature 325 °C and pressure 2.1 MPa was showed high CO conversion and yield of hydrocarbon. Additionally, properties of Cu-ZnO/Pd-b catalyst was significantly improved comparing with other catalyst. The researcher suggested that Cu-ZnO/Pd-b might be used for synthesis LPG from methanol due to its high activity and high yield hydrocarbon.

            This study provides helping the conversion of methanol to LPG with high performance and environmentally friendly. However, this catalyst is some limitation.

1)               The researcher did not study durable, and specific surface area of Cu-ZnO/Pd-b catalyst. The researcher might miss effect related to activity of catalyst. Actually, the catalyst should be studied durable and specific surface area of catalysts. For Example, Congming Li et al. (2014) study durable, and specific surface area of CZZA/Pd-b catalyst. The results found that CZZA/Pd-b catalyst could be operate 100 hours by this catalyst without regenerate coke on catalyst. The specific surface area of CZZA/Pd-b catalyst is 17.4 square metres per gram.

2)         This study did not investigate mechanism of reaction, by mechanism should be studied major topic, which is important for the study effect of metal on catalyst. All catalyst should be studied because when they added metal on catalyst found that the product and byproduct from reaction not coincide. Then, they known the effect of metal to reaction (Congming Li et al., 2014).

3)         This study used only SEM to confirm the dispersion of metal on catalyst. The researcher should be studied dispersion by other technique to confirm the presence of Cu, ZnO, and Pd metal on catalyst.  One of common method for the study dispersion of catalyst is Energy-dispersive X-ray spectroscopy (EDX) technique. Using a combination of SEM is more performance for analyzer catalyst than using only one this method (Congming Li et al., 2014).

            The strength of this study is that the ratio of catalyst, component and optimum condition. These method are widely major problem of catalyst is coke formation on catalyst. Another advantage of this study is that the product from reaction could be decreased LPG from crude oil.  

References

Qingjie Ge, Yu Lian, Xingdong Yuan, Xiaohong Li, Kaoru Fujimoto (2008). High performance Cu– ZnO/Pd-b catalysts for syngas to LPG. Catalysis Communications, 9, 256–261

Congming Li, Xingdong Yuan, Kaoru Fujimoto (2014). Development of highly stable catalyst for methanol synthesis from carbon dioxide. Applied Catalysis A: General, 469, 306– 311