Multiwalled carbon nanotube-supported Pt (Pt/MWNT) nanocomposites were prepared by both the aqueous solution reduction of a Pt salt (HCHO reduction) and the reduction of a Pt ion salt in ethylene glycol solution. For comparison, a Pt/XC-72 nanocomposite was also prepared by the EG method. The Pt/MWNT catalyst prepared by the EG method has a high and homogeneous dispersion of spherical Pt metal ...

Industrial bubble column reactor for Fischer-Tropsch (FT) synthesis includes complex hydrodynamic, chemical and thermal interaction of three material phases: population of bubbles of different sizes, liquid and catalyst particles suspended in liquid. To simulate FT bubble column, a Computational Fluid Dynamics model is described here. The model is based on Eulerian multifluid formulation and ac...

Cone-shaped nanostructures of mixed composition (nanocones) and largely graphitic nanofibers were synthesized on silicon substrates using iron/platinum alloy nanoparticles as the catalyst in a direct-current plasma enhanced chemical vapor deposition reactor. The catalyst nanoparticles were monodisperse in size with an average diameter of 3 (±1) nm. The nanocones were produced on laterally widel...

a two-dimensional (2d) single particle model for the copolymerization of propylene-ethylene with heterogeneous ziegler-natta catalyst is developed. the model accounts for the effects of the initial shape of the catalyst and carck/ pore patterns on the copolymer composition, polymerization rate and the average molecular weight properties. the spherical and oblate ellipsoidal shapes of catalyst p...

Carbon-supported platinum (Pt) and palladium (Pd) alloy catalyst has become a promising alternative electrocatalyst for oxygen reduction reaction (ORR) in proton exchange membrane fuel cells. In this work, the synthesis of highly active and stable carbon-supported Pt-Pd alloy catalysts is reported with a room-temperature electron reduction method. The alloy nanoparticles thus prepared show a pa...

single-walled carbon nanotubes (swnts) with high yield and quality were synthesized using chemical vapor deposition (cvd) over co-mo/ mgo nanocatalyst in a fluidized bed reactor. different parameters such as temperature, the ratio of hydrocarbon source to hydrogen, the flow rate of gas, growth time, the size of catalyst particles, heating rate, and the kind of hydrocarbon source were examined t...

Aggregation in heat-treated Nafion ionomer dispersion and 117 membrane are investigated by 1H and 19F Nuclear Magnetic Resonance (NMR) spectra, spin-lattice relaxation time, and self-diffusion coefficient measurements. Results demonstrate that heat-treatment affects the average Nafion particle size in aqueous dispersions. Measurements on heat-treated Nafion 117 membrane show changes in the 1H i...

tungsten trioxide nanoparticles with two different sizes (average particle sizes about 50 and 80 nm) were prepared by the spray pyrolysis method. photo degradation of congo red (azo dye) showed that photo catalytic property of the as-prepared wo3 nanoparticles with average size about 80 nm is higher than the sample with average size about 50 nm. photo degradation of rhodamine b (cationic triary...

in this study, sio2 nanoparticles were successfully synthesized via sol-gel precipitation method and the effects of different parameters such as temperature, ethanol, ammonia and tetraethylorthosilicate (teos) contents based on water were investigated in a systematic way applying taguchi experimental design method. it was found that, among all the investigated parameters, ethanol as a co-solven...