(600y) Bamboo-Shaped Carbon Nanotubes and Hydrogen Produced by Catalytic Decomposition of Methane Over Ni-Cu-Zn Supported On MCM-22 Catalyst | AIChE

(600y) Bamboo-Shaped Carbon Nanotubes and Hydrogen Produced by Catalytic Decomposition of Methane Over Ni-Cu-Zn Supported On MCM-22 Catalyst

Authors 

Saraswat, S. K. - Presenter, Indian Institute of Technology, Delhi


Bamboo-shaped carbon nanotubes and hydrogen produced by catalytic decomposition of methane over Ni-Cu-Zn supported on MCM-22 catalyst

Sushil Kumar Saraswat, K.K. Pant#

Department of Chemical Engineering,

IIT Delhi, Hauz Khas, New Delhi, India-110016

# E.Mail: kkpant@chemical.iitd.ac.in

Tele.: + 91-1126596172 Fax: + 91-1126581120

Thermo catalytic decomposition of methane (TCD) has become an attractive alternative route both for clean hydrogen and for value-added carbon material due to its simplicity in process and high efficiency [1,2]. An additional advantage of this process is that, in principle, it does not produce any carbon dioxide. On the other hand, it is also produce carbon nanotubes which is recognized as one of the most important materials due to their superior surface property, high tennacity, high electron conductivity, excellent field emission property, metal and semiconductor property [3-5]. The effects of varying the catalysts used in TCD have been widely reported in the literature [6,7 ].There has been attempts to use catalysts to reduce the maximum temperature of the thermal decomposition of hydrocarbons. Common catalysts used are mainly transition and noble metals such as Ni, Fe, Pd, Co, etc., supported on high surface area ceramic substrates such as A12O3 and SiO2, etc. Among all the catalysts investigated, nickel appears to provide the highest activity and is most commonly used for this purpose [8].

This paper investigated the production of hydrogen and filamentous carbon from thermo catalytic decomposition of methane in a fixed-bed reactor using Ni-based catalysts. Highly active and stable Ni-Cu-Zn/MCM-22 catalysts were prepared by wet impregnation method. The catalytic activity of the Ni-Cu-Zn/MCM-22 catalysts was carried out at 650-800 oC and at atmospheric pressure. The influence of Cu and Zn content was investigated over Ni/MCM-22 samples with different Cu/Zn ratios. The activity results revealed that a certain amount of Cu/Zn could enhance methane decomposition activity of Ni/MCM-22 catalyst. 50%Ni-5%Cu-5%Zn/MCM-22 catalysts provide more than 80% methane conversion and carbon yield at 750 oC and WHSV 0.6 Lgcat-1h-1. It was observed that produced carbon filaments are deposited mainly in the form of multiwalled carbon nanotubes. The physicochemical characteristics of fresh and spent catalysts were characterized by BET-surface area, X-ray diffraction (XRD), temperature-programmed reduction (TPR), thermogravimetric analysis (TGA), scanning electron microscopy (SEM) and transmission electron microscopy (TEM).

References

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