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Bentonite, a 2:1 type swellable phyllosilicate clay mineral having exchangeable inorganic cations in the interlamellar space to nullify their charge deficiency was used to generate palladium nanoparticles. It was found that 1% w/w palladium nanoparticles were generated in the interlamellar space using adsorption excess technique. The synthesized catalysts were characterized by using XRD, TEM, BET surface area analysis, and AAS. The modified clay catalysts were tested for their catalytic activity towards the hydrogenation of benzaldehyde to benzyl alcohol in liquid phase using a high-pressure reactor at various temperatures and pressures. High selectivity (100%) towards the desired product of benzyl alcohol was achieved with conversion over 80% in all cases. These results showed different hydrogen dependency for the reaction at various temperatures. The kinetics of the reaction was studied using Langmuir Hinshelwood single site model. The rate constant was determined using pseudo first-order kinetics and activation energy for benzaldehyde hydrogenation was calculated at various temperatures using Arrhenius equation and was found to decrease with increase in temperature.

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A dense carbon nanotube [CNT] forest was formed by chemical vapor deposition [CVD] using spin-coated iron oxide (Fe 2 O 3 ) thinfilm on Si substrate. The nanoforest contains carbon nanotubes was obtained by feeding a mixture of acetylene, hydrogen and nitrogen [N 2 :H 2 : C 2 H 2 D 27: 27: 5 mL/min] for 45 min at 700 C in the CVD chamber. The CNT forest was subjected to analyze the phase, crystalline quality and microstructure using X-ray diffraction, Raman spectroscopy, and scanning electron microscopy [SEM], respectively. The elemental analysis and mapping were also studied using energy dispersive X-ray spectroscopy [EDX]. The morphology, shape and size of the nanotubes were characterized by transmission electron microscopy. The obtained carbon nanotubes were of length 13-14 mm and diameter of 10-100 nm over Fe thin-film coated on Si substrate, which makes this CNT/ Fe/Si hybrid material could be a better candidate for field emission applications.

Multiwalled carbon nanotubes (MWCNT) are synthesized by isobutane decomposition at 700 °C over aspurchased and iron-loaded K10-montmorillonite catalysts. The results show that, upon reduction at 500 °C, K10 catalyzes isobutane decomposition. Few carbon fibers accompany the prevailing carbon flakes formation. Upon Na + exchange or by increasing the reduction temperature, the activity of the clay decreases. Fe-K10 behaves as a bifunctional catalyst: on added metal sites, MWCNT preferentially form, while on the support, carbon flake formation mainly occurs. At a given metal load, the increase of the reduction temperature up to 700 °C or the use of Na + -exchanged K10 as a support generally leads to an enhancement of the selectivity to MWCNT, because of the diminishing of the support active sites. Under the present reaction conditions, Fe supported on Na + exchanged K10 are the most active among the investigated catalysts. MWCNT copiously form, both at low and high metal load, and exhibit the highest structural order.