چكيده به لاتين
In recent years, the discussion of increasing environmental pollution due to the expansion of industrial, commercial, economic activities, etc., has attracted the attention of many researchers as a fundamental challenge, because these activities affect all aspects of the environment, including soil resources, they have affected the water, atmosphere, etc. and have created serious risks for the health of humans and other living beings on the planet. Therefore, the efforts of concerned researchers have been directed towards finding a solution to prevent pollutants from entering the environment and also to clean the environment from the pollutants that have entered it, and we have tried not to be an exception to this rule. As a result, we tried to design and synthesize efficient nanocomposites so that they can help us achieve this goal with their catalytic activity. Keggin type polyoxometalate structures are nano-catalysts capable of redox reactions and can act as an efficient catalyst in reducing water pollutants and desulfurization of fuel. Despite their unique features such as unique chemical and electronic properties, etc., these structures have defects such as low surface area, lack of recycling due to high solubility in aqueous environments, sensitivity to environmental pH, etc. As a result, with a detailed design and composite of these compounds with metal-organic frameworks and placing them in the pores of these chachubs, we were able to synthesize two nanocomposites H3PSr3Mo9O37@ZIF-67 (In) and H3PSr3Mo9O37@MIL-101 (Cr) (In). show Synthesized nanocomposites were able to overcome many defects of POM structures, such as low surface area, non-reusability and lack of stability at high pH 6 and 7, and on the other hand, the thermal stability of the nanocomposites made compared to each of these parts a lone, increased. We used nanocomposite with ZIF-67 substrate to clean up water sources, so that this nanocomposite was able to reduce 4-nitrophenol in the presence of NaBH4 reducer in a period of 90 seconds with an efficiency of 99.43% and an apparent rate constant of Kapp=0.0618 S-1. and we also used the nanocomposite with MIL-101 (Cr) substrate in the oxidative desulfurization process of the model fuel, and this nanocomposite was also able to work in the presence of various oxidants such as H2O2/AA with a volume and ratio of 2:1 mL Model fuel desulfurization process in 60 minutes with 87.45% efficiency and apparent speed constant Kapp=0.0267 min-1 and also in the presence of H2O2/FA oxidant with volume and mL ratio of 2:1 in 40 minutes with efficiency of 94.47% and apparent rate constant Kapp=0.0488 min-1.
