Preparation Of Mo/LDH Nanocomposite And Degradation Of Methyl Orange In CWAO

The paper focused on the innovation of mild reaction conditions for catalytic wet oxidation (CWAO), and established quantitative structure-property relationships (QSPR) between the structure of dyes and the discoloration rate of dyes. Through delamination of LDH and then preparation of Mo/LDH nanocomposites by a layer-by-layer self-assembly method. Then investigated the affect of the composition ratio between LDHs and H3Mo12O40P and the delamination time of H3Mo12O40P in the manufacturing process, and studied the degradation of methyl orange dyes wastewater in CWAO process.The results was shown as follows.The DFT-based quantum chemical descriptors were obtained for the dye molecular and partial lease squares (PLS) regression was employed for QSPR model development.Two components were selected in the QSPR model. The absolute values of W*[1] for that absolute hardness (?) and the most negative atomic net charges of the molecule (q-) were 0.806657 and 0.561769 demonstrates ? and q-are the main cause for the first component. The second PLS component is loaded on descriptors dipole moment (?) for which the W*[2] values were 0.906712.Two components were selected in model, which account for 0.733 of the variance of the predictor variables and 0.979 of the variance of the dependent variable. The optimal QSPR model with a cross-validation Q2(cum) value of 0.845 indicates that the QSPR model has sufficient predictive ability and robustness. The equation was obtained with the descriptors: Y=51.5042+252.644?+0.899607?+102.427 q-.(1) The Zn-Al-LDHs was prepared by coprecipitation method and delaminated in formamide with the assisted of ultrasonic to obatined the positively charged layer. Then added the H3Mo12O40P sheet in the LDHs to preparation of Mo/LDH nanocomposites by a layer-by-layer self-assembly method. The X-ray diffraction (XRD), N2 adsorption measurements, Scanning electron microscopy (SEM), Zeta potential, Thermogravimetric analysis (TG-DSC) and X-ray photoelectron spectrometer (XPS) were used to investigated the affect of Zn-Al-LDH and H3Mo12O40P ratio for Mo/LDH nanocomposites strcuture and properties. The results showed that H3Mo12O40P and LDHs successful reorganization and maintained the properties of LDHs. When the composition ration was 1:0.4, the Mo/LDH nanocomposite has the highest crystallinity and Mo was in+6 form. It has a good thermal stability stability and a maximum value of the Zeta potential, and it has the catalytic activity with 74.2% of discoloration and 66.2% of TOC removal efficiency for methyl orange in CWAO process under room temperature and press. The leaching rate of Mo was 0.004 g/g and the discoloration rate of methyl orange was still 63.4% after 5 times reused.(2) The X-ray diffraction (XRD), N2 adsorption measurements, Scanning electron microscopy (SEM), Thermogravimetric analysis (TG-DSC) and X-ray photoelectron spectrometer (XPS) were used to investigated the affect of delamination time of H3Mo12O40P for Mo/LDH nanocomposites strcuture and properties. The results showed that Mo/LDH nanocomposite prepared under the H3Mo12O40P delamination time of 24h has layer structure and a higher degree of crystallinity, Mo was in the form of+6, and it has the catalytic activity with 68.3% of discoloration and 58.6% of TOC removal efficiency for methyl orange in CWAO process under room temperature and press. The leaching rate of Mo was 0.006 g/g and the discoloration rate of methyl orange was still 60.1% after 5 times reused.