| Water is the source of life, and it is essential for human survival. However, with the rapid development of economy, environmental issues and the water pollution have become increasingly severe, so developing a sewage treatment system is urgently needed. Currently, artificial aeration repair process, in other words the artificial oxygen techniques, are the most efficient measures among the water purify methods. It has been attracted great attention due to its less pollution to the environment, high efficiency in disposing of sewage and easy to operate. Hence, Aeration process has become a hot topic in the wastewater treatment area.Until now, a large amount of research focus on improving aeration mode or aeration equipment. However, there are still much problems remain, such as operation with varying degrees of difficulty, feasibility low and high cost. If the aeration processes could be improved from the molecular level, unexpected results may be achieved. CNTs acting as a new material has already applied to the water treatment of environmental engineering owing to its high chemical stability, mesopore and surface active.In consideration of the CNTs is more expensive than conventional ones and easily assembled into a bundle in the water. In this paper, we prepared the MnO2-filled multiwalled carbon nanotube/polyaniline nanocomposites by using the CNTs as carrier for its high mechanical strength and large specific surface area and loading the conductive functional polymer polyaniline and MnO2 with high adsorption capacity and low cost.The CNTs-MnO2 composites were synthesized using in situ polymerization. The samples were further researched and analysized by scanning electron microscopy (SEM), transition electron microscopy (TEM), X-ray diffractometer (XRD) and fourier transform infrared spectrometer (FTIR). The observation reveals that the CNTs-MnO2 composites show enhance Gas-liquid mass transfer efficiency in comparison to the untreated CNTs. The enhanced properties may be mainly attributed to the composite material possess higher porosity, giving rise to the increase of the active site during the process of fabricating the CNTs-MnO2 nanocomposites. Furthermore, the CNT-MnO2/PANI nanocomposites were also successfully synthesized by using in situ polymerization with the CNTs-MnO2 as material, which were characterized by scanning electron microscopy (SEM), transition electron microscopy (TEM), X-ray diffractometer (XRD) and fourier transform infrared spectrometer (FTIR). The results show the polyaniline particles are covered onto the surface of the binary composite material, giving rise to increasing surface-active of the material. At the same time, a large number of amino and imino functional groups was added, which is advantageous to the oxidation-reduction reaction of aeration process.Moreover, we studied the effects of composites for oxygenation rate and gas-liquid mass transfer, as well as the effects of dose and type of the solid-phase medium for strengthening gas-liquid mass transfer capacity. The results confirmed that the CNT-MnO2/PANI nanocomposites show enhance gas-liquid mass transfer capacity compared to neat CNTs and CNTs-MnO2 without PANI addition and the gas-liquid mass transfer capacity is related to does of the solid-phase medium. Meanwhile, the CNT-MnO2/PANI nanocomposites possess high chemical stability so that it can be recycled. In addition, the cost of experiments had reduced greatly after compounding by calculating. Therefore, these factors can effectively reduce the cost of aeration process. And we also provides an experimental basis for the practical application of the water treatment process. |
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