Design Of Bimetallic Porous Materials And Its Performances Reduction Of P-Nitrophenol

With the continuous development of the chemical industry,the nitro compound water pollution is becoming more and more severe.P-nitrophenol?P-NP?is one of the common toxic pollutants in wastewater,which can pose a serious threat to ecosystem and human health due to enriching in aquatic organisms for a long time.Catalytic reduction of P-nitrophenol to P-aminophenol should reduce its toxicity as well as obtain important chemical and pharmaceutical intermediates.The method has attracted wide attention due to advantages such as mild reaction conditions and simple operation.Aiming at the scarcity and high cost of the precious metal catalysts,CuO-CSs and CuO/Cu-Co₃O₄were prepared by loading CuO onto carbon spheres and ZIF-67-derived porous metal oxides,respectively,and characterized by SEM,XRD,BET and XPS.Using Na BH₄ as the reducing agent,the catalytic performance of P-NP reduction,the catalytic kinetics and the mechanism of reduction over CuO/Cu-Co₃O₄ were investigated.The results of microscopic characterization show that the CuO-CSs has good dispersion,high sphericity and good pore size.It was found that the copper nitrate loaded on the surface of the support was completely converted to CuO,and the activity of the catalyst was also increased as calcination temperatures increase.The CuO-CSs showed good catalytic performances for reduction of P-NP when prepared using a loading amount of 10%by 300?calcination.The initial concentration of P-NP,the amount of catalyst,the amount of reductant and the reaction temperature have definite influences on the catalytic reduction reaction.The reaction rate decreases with the increase of the initial concentration of P-Nitrophenol.As the amount of catalyst,reductant and reaction temperature increase,the reaction rate increases.After 5 times of using CuO-CSs catalyst,the conversion still reached 100%,and the shape of CuO-CSs remained spherical.CuO/Cu-Co₃O₄ has a fluffy and porous structure.CuO/Cu-Co₃O₄with different Cu/Co mole ratio has different morphologies,but they are still mesoporous materials with uniform pore size distribution.After 3 min of reaction,the P-Nitrophenol could be completely reduced at room temperature when the molar ratio of Cu/Co is 3:7,the amount of reductant and catalyst are 0.1 mol/L and 0.02 g,respectively.CuO/Cu-Co₃O₄ had no obvious deactivation and no change in the morphology and structure of the catalyst after reusing for five times.The characteristic peaks of Co₃O₄,CuO and Cu could be still observed in the XRD patterns of the catalyst after reusing.The kinetic study shows that the reaction is first-order kinetic reaction with activation energy Ea=39.97 k J/mol.it is proposed that CuO/Cu-Co₃O₄ has excellent catalytic activity due to the synergistic effect of Co and Cu and the oxygen vacancy.