Preparation and catalytic applications of nanomaterials: a review

Abstract

Catalyst plays a very important role in the chemical industries. Catalysts have been used in processes like the workup of fuels such as oil, gas and coal, purification of effluents and industrial waste gases etc. Heterogeneous catalysts are gaining much attention as compared to the homogeneous catalysts as it confers more selectivity and provides better yield. Research in new catalytic materials or optimization of existing catalyst systems is of enormous importance in order to increase the efficiency of the catalyst resulting in higher product yields and purities.Currently, the research is more focused towards the nanostructured catalyst with enhanced physiochemical properties. Nanoscale catalysts have high specific surface area and surface energy, which ultimately lead to the high catalytic activity. Nano-catalyst improves the selectivity of the reactions by allowing reaction at a lower temperature, reducing occurrence of side reactions, higher recycling rates and recovery of energy consumption. Therefore, these are widely used in green chemistry, environmental remediation, efficient conversion of biomass, renewable energy development and other areas of interest. In this review prospects, paradox and perspective of preparation and catalytic application of nanomaterials in organic synthetic chemistry is reviewed, and an outlook of their developments is discussed.Zeolites sparked a revolution in the field of catalysis due to the special structure and performance. However, processing problem has been encountered with the zeolites such as the catalytic cracking of heavy oil macromolecules and immobilization of the macrocyclic complexes. Scientists had discovered mesoporous materials at early 18 th century. Since, that time mesoporous materials had become attraction for the material, chemical, physical and other disciplines. Mesoporous Silica Nanocatalyst is having the wide catalytic applications (Table 1).As, nanostructured mesoporous materials have large surface area, high activity and a great adsorption capacity 31-34 ( Figure.4). Figure 4. Variation in the pore size and particle size of the Mesoporous silica Nanocatalys. Due to an increasing interest and acceptance in the field of formation and applicability of MNB's, many new areas have been introduced with the advantages being provided by them. Theoretically, it is calculated that due to high pressure, and size in nanobubbles, the air should escape out of the bubble in microseconds. But, practically another aspect was noticed of the MNB's, i.e. under the appropriate circumstances, these MNB's can shape freely and remain stable for a comprehensive period of time. Hence, such property can be used for various different fields, like-The MNBs can be used for bioremediation purposes. Due to the large surface area of MNB, and high stagnation time in the water, sparging with MNB proves to be a better option of increasing the content of oxygen, than sparging with the macrobubbles. Hence, the water purification can be achieved with the help of MNB technology 164-166 . Mo...

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