Study On Preparation Of MCM-41 Molecular Sieve Adopting Ultrasonic Impregnation And Its Desulfurization Performance

Hydrogen sulfide is a rotten and toxic gas.Hydrogen sulfide could corrode existing pipelines and production facilities.In addition,the international environmental protection laws for industrial hydrogen sulfide emissions have strict requirements.Therefore,the study of hydrogen sulfide removal on the industrial level and environmental protection is of great significance.In this paper,using hydrogen sulfide,nitrogen and oxygen gas mixture for simulate raw gas,modified MCM-41 molecular sieve adopted ultrasonic impregnation by metal were prepared.The composition and structure of adsorbents were characterized by thermogravimetric-differential thermal analysis?TG-DTA?,X-ray diffraction?XRD?,fourier transform infrared?FT-IR?,specific surface area?N₂-BET?,temperature programmed reduction?H₂-TPR?,X-ray photoelectron spectroscopy?XPS?,scanning electron microscope?SEM?and transmission electron microscope?TEM?.Effects of preparation and process condition on the performance of hydrogen sulfide removal were studied in a fixed bed reactor.The main results are as following:?1?Cobalt modified MCM-41 molecular sieve adsorbent:the absorbent with Co?NO₃?₂ impregnation concentration of 10%,ultrasonic time of 2 h,calcination temperature of 550 ^oC was found to give the best preparation conditions.The gas flow rate of 20 mL/min and adsorption temperature of 45 ^oC was found to give the best process conditions.The saturated H₂S capacity and H₂S removal rate reached 52.5 mg/g and47.8%,respectively.The H₂S adsorption kinetics was satisfied with Bangham equation and the ideal adsorption equation was obtained by fitting.?2?Manganese modified MCM-41molecular sieve adsorbent:the absorbent with Mn?NO₃?₂ impregnation concentration of 8%,ultrasonic time of 2.5 h,calcination temperature of 550 ^oC was found to give the best preparation conditions.The gas flow rate of 20 mL/min and adsorption temperature of 55^oC was found to give the best process conditions.The saturated H₂S capacity and H₂S removal rate reached 52.0 mg/g and 55.3%,respectively.The H₂S adsorption kinetics was satisfied with Bangham equation and the ideal adsorption equation was obtained by fitting.