الفهرس 
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Abstract
Summary
i
SUMMARY
The present thesis “preparation and characterization of nanoparticles for catalytic applications” comprises three chapters:
The first chapter includes an introduction to:
Catalysis especially heterogeneous catalysis.
Nanoparticles and focus on metals (cobalt, nickel and nano zero valent iron), metal oxides (cobalt oxide, nickel oxide and akaganeite) and mixed oxides (cobalt ferrite and nickel ferrite).
Nitro compounds, removal of 4- nitrophenol by different methods especially reduction method and literatures survey to reduction reaction of 4-nitrophenol.
The second chapter includes:
Materials and instruments used in this work
Experimental methods for preparation of metals (cobalt, nickel and nano zero valent iron), metal oxides (cobalt oxide, nickel oxide and akaganeite) and mixed oxides (cobalt ferrite and nickel ferrite).
characterization tools (TEM, XRD, VSM, EDX and BET) were used in this work.
General procedure for the reduction reaction of 4-nitrophenol.
The third chapter presents the results and their discussions. This chapter is divided into three sections.
The first part in this chapter discussed ”metal nanoparticles”
a) Nano Zero Valent Iron characterized by XRD which showed cubic phase structure of NZVI and the average crystallite size was 11.3 nm, TEM showed that the NZVI were spherical in shape with size range from 8.86 to 11.2 nm, BET surface area values were determined as 81.491m2/g for NZVI, VSM confirmed the ferromagnetic behavior of NZVI at room temperature and studied catalytic activity of NZVI toward reduction reaction of 4-nitrophenol and determined the rate constant k=3.22×10-3s-1.
Nickel nanoparticles characterized by XRD which showed cubic phase structure of nickel nanoparticles and the average crystallite size was 7.5 nm, TEM showed that the nickel nanoparticles were spherical in shape with average particle size 3.22nm, BET surface area values were determined as 4.405m2/g for nickel nanoparticles, VSM confirmed the ferromagnetic behavior of nickel nanoparticles at room temperature and studied catalytic activity of nickel nanoparticles toward reduction reaction of 4-nitrophenol and determined the rate constant k =1.1×10-3 s-1.
c) Cobalt nanoparticles characterized by XRD which showed the amorphous cobalt nanoparticles as no diffraction peaks appeared, TEM showed that the cobalt nanoparticles were spherical in shape with size range from 6.4 to 9.1nm, BET surface area values were determined as 35.173m2/g for cobalt nanoparticles, VSM confirmed the ferromagnetic behavior of cobalt nanoparticles at room temperature and studied catalytic activity of cobalt nanoparticles toward reduction reaction of 4-nitrophenol and determined the rate constant k =2.5×10-3 s-1.
The second part discussed ”metal oxide nanoparticles”
a) Cobalt oxide nanoparticles characterized by XRD which showed cubic phase structure of cobalt oxide nanoparticles and the average crystallite size was 50 nm, TEM showed that the cobalt oxide nanoparticles were spherical in shape with size range from 2.16 to 6.44nm, BET surface area values were determined as 8.462m2/g for cobalt oxide nanoparticles and studied catalytic activity of cobalt oxide nanoparticles toward reduction reaction of 4-nitrophenol and determined the rate constant k=1.82×10-3s-1.
b) Nickel oxide nanoparticles characterized by XRD which showed rhombohedral phase structure of nickel oxide nanoparticles and the average crystallite size was 12.1nm, TEM showed that the nickel oxide nanoparticles were spherical in shape with size range from 5.22 to 8.76nm, BET surface area values were determined as 11.050m2/g for nickel oxide nanoparticles and studied catalytic activity of nickel oxide nanoparticles toward reduction reaction of 4-NP and determined the rate constant k =2.5×10-3 s-1.
c) Akaganeite nanoparticles characterized by XRD which showed tetragonal phase structure of akaganeite nanoparticles and the average crystallite size was 15.6 nm, TEM showed that the akaganeite nanoparticles were spherical in shape with size range from 6.60 to 9.44nm, BET surface area values were determined as 144.928m2/g for
akaganeite nanoparticles and studied catalytic activity of akaganeite nanoparticles toward reduction reaction of 4-NP and investigated that the akaganeite nanoparticles inactive toward reduction reaction of 4-NP.
The last part discuss characterization of ”mixed oxide nanoparticles”
a) Cobalt ferrite nanoparticles characterized by XRD which showed rhombohedral phase structure of cobalt ferrite nanoparticles and the average crystallite size was 3 nm, TEM showed that the cobalt ferrite nanoparticles were spherical in shape with size range from 1.44 to 2.88 nm, BET surface area values were determined as 43.721m2/g for cobalt ferrite nanoparticles, VSM confirmed the ferromagnetic behavior of cobalt ferrite nanoparticles at room temperature and studied catalytic activity of cobalt ferrite nanoparticles toward reduction reaction of 4-NP and determined the rate constant k =3.49×10-4 s-1 .
b) Nickel ferrite nanoparticles characterized by XRD which showed cubic spinel structure of nickel ferrite nanoparticles and the average crystallite size was 19.6 nm, TEM showed that the nickel ferrite nanoparticles were spherical in shape with size range from 10.44 to 15.1 nm, BET surface area values were determined as 30.405m2/g for nickel ferrite nanoparticles, VSM confirmed the ferromagnetic behavior of nickel ferrite nanoparticles at room temperature and studied Catalytic activity of nickel ferrite nanoparticles toward reduction reaction of 4-NP and determined the rate constant k =2.3×10-3 s-1.