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Aim and Objectives: The focus of the present work is to synthesize ZnO/C composite using dextrose as carbon source by combustion method and study the comparative evaluation on one-pot synthesis of β-acetamido- β-(phenyl) propiophenone over ZnO nanoparticles and ZnO/C composite catalyst. Materials and Methods: The ZnO nanoparticles has been synthesized by sol-gel method using zinc nitrate and NaOH and ZnO/Carbon composites by combustion method using zinc nitrate and dextrose as carbon source. The resulting gel was placed in a preheated muffle furnace at 400o C. The solution boils and ignites with a flame. On cooling highly amorphous powder of ZnO/Carbon composite is obtained. Results: The XRD patterns reveal the hexagonal phase with Wurtzite structure and the nanocrystalline nature of the catalysts. The SEM image of ZnO/C composite showed that it contains spherical particles with an average size of 41 nm. The average particle size of the composite was around 60nm by DLS method. The catalytic activity of the ZnO/Carbon composites has been analyzed by one-pot four-component condensation of benzaldehyde, acetophenone, acetyl chloride and acetonitrile. The feed molar ratio of 1:1 (Bz:AP) and catalyst loading of 30 mol% is found to be the optimal condition for βacetamido ketone conversion over ZnO/carbon composite. Conclusion: The substantial catalytic activity of the synthesized ZnO/C composite materials was tested by one-pot fourcomponent condensation of benzaldehyde (Bz), acetophenone (AP), acetyl chloride (AC) and acetonitrile (AN) which showed a high β-acetamido ketone conversion under the optimized reaction conditions. It has also been found that the catalyst is very stable and reusable.

Activated carbon was synthesized from cooked food waste, especially dehydrated rice kernels, by chemical activation method using NaOH and KOH as activating agents. It was then characterized by ultimate and proximate analysis, BET surface analysis, XRD, FTIR, Raman and SEM. The XRD patterns and Raman spectra confirmed the amorphous nature of the prepared activated carbons. Ultimate analysis showed an increase in the carbon content after activation of the raw carbon samples. Upon activation with NaOH and KOH, the surface area of the carbon sample was found to have increased from 0.3424 to 539.78 and 306.83 m2g-1 respectively. The SEM images revealed the formation of heterogeneous pores on the surface of the activated samples. The samples were then tested for their adsorption activity using acetic acid and methylene blue. Based on the regression coefficients, the adsorption kinetics of methylene blue dye were fitted with pseudo-second order model for both samples. Similarly, the Freundlich isotherm was found to be a better fit than Langmuir isotherm for both samples. The activity of thus prepared activated carbons was found to be comparable with the commercial carbon.

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