A series of Na-W-Mn-Zr/SiO_(2)catalysts promoted by different contents of S or/and P were prepared and their catalytic performance for oxidative coupling of methane was investigated to clarify the effect of S and P on...A series of Na-W-Mn-Zr/SiO_(2)catalysts promoted by different contents of S or/and P were prepared and their catalytic performance for oxidative coupling of methane was investigated to clarify the effect of S and P on the Na-W-Mn-Zr/SiO_(2)catalyst.The catalysts were characterized by X-ray diffraction(XRD)and X-ray photoelectron spectroscopy(XPS).From the characterization results,it is found that the addition of S and P to the Na-W-Mn-ZffSiO_(2)catalyst helps the formation of active phases,such asα-cristobalite,Na2WO4,ZrO_(2),and Na2SO4.Moreover,the addition of S and P increases the concentration of surface-active oxygen species by improving the migration of active components from the bulk phase to the surface of the catalyst.According to the activity test,impressive methane conversion and C2 hydrocarbons yield were obtained at a low temperature of 1023 K over the six-component Na-W-Mn-Zr-S-P/SiO_(2)catalyst,which contained 2 wt%S and 0.4 wt%P simultaneously.The deactivation of Na-W-Mn-Zr-S-P/SiO_(2)was due to the loss of surface active components.展开更多
基金supported by the National Natural Science Foundation of China(20676116)
文摘A series of Na-W-Mn-Zr/SiO_(2)catalysts promoted by different contents of S or/and P were prepared and their catalytic performance for oxidative coupling of methane was investigated to clarify the effect of S and P on the Na-W-Mn-Zr/SiO_(2)catalyst.The catalysts were characterized by X-ray diffraction(XRD)and X-ray photoelectron spectroscopy(XPS).From the characterization results,it is found that the addition of S and P to the Na-W-Mn-ZffSiO_(2)catalyst helps the formation of active phases,such asα-cristobalite,Na2WO4,ZrO_(2),and Na2SO4.Moreover,the addition of S and P increases the concentration of surface-active oxygen species by improving the migration of active components from the bulk phase to the surface of the catalyst.According to the activity test,impressive methane conversion and C2 hydrocarbons yield were obtained at a low temperature of 1023 K over the six-component Na-W-Mn-Zr-S-P/SiO_(2)catalyst,which contained 2 wt%S and 0.4 wt%P simultaneously.The deactivation of Na-W-Mn-Zr-S-P/SiO_(2)was due to the loss of surface active components.
