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A series of Na-W-Mn-Zr/SiO2 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/SiO2 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-Zr/SiO2 catalyst helps the formation of active phases, such as α-cristobalite, Na2WO4, ZrO2, 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/SiO2 catalyst, which contained 2 wt% S and 0.4 wt% P simultaneously. The deactivation of Na-W-Mn-Zr-S-P/SiO2 was due to the loss of surface active components.
A series of Na-W-Mn-Zr / SiO2 products 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- 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-Zr / SiO2 catalyst helps the formation of active phases, such as α-cristobalite, Na2WO4, ZrO2, and Na2SO4. Furthermore, 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, an impressive methane conversion and C2 hydrocarbon yield were obtained at a low temperature of 1023 K over the six-component Na-W-Mn-Zr-SP / SiO2 catalyst , which contained 2 wt% S and 0.4 wt% P simultaneously. The deactivation o f Na-W-Mn-Zr-S-P / SiO2 was due to the loss of surface active components.