| Coal gasification to generate electric energy was a main way of coal clean utilization, especially coal gasification combined cycle power generation （IGCC） technology has attracted widespread concern of society with high heat efficiency, economy. The key was high temperature coal desulfurization to achieve this power generation technologies, because the existence of sulfide gas will corrode equipment, and has a great harm to human health and environment. On the other hand, the sulfur resource was lack, so the regeneration study of high temperature coal gas desulfurization sorbent and elemental sulfur recycle in the regeneration exhaust were significant.The preparation process and regeneration mechanism of cerium oxide high temperature coal gas desulfurization sorbent was relative simple, and the regeneration reaction rate was fast, especially the regeneration gas product was elemental sulfur under SO2 atmosphere. Because of these advantages, so this paper was supported by the National Natural Science Foundation （NO.21276172）, discussing the regeneration behavior of cerium oxide high temperature coal gas desulfurization under O2 atmosphere, SO2 atmosphere and O2-SO2 atmosphere in the fixed bed, and fitting the regeneration kinetics equations of cerium oxide high temperature coal desulfurization sorbent under O2 atmosphere and SO2 atmosphere using the regress function of MATLAB program. Through the content detection of exhaust in outlet, and study the rule of elemental sulfur production in regeneration exhaust under O2 atmosphere, SO2 atmosphere, O2-SO2 atmosphere, and analyzed the phase composition and morphology of sorbent by X-ray diffraction（XRD）、Scanning electron microscopy（SEM）.The results as shown:The regeneration of cerium oxide high temperature coal gas desulfurization sorbent under O2 atmosphere, the chemical reactions were:Ce2O2S （s）+2O2 （g）'2CeO2 （s）+SO2 （g） （main）Ce2O2S （s）+SO2 （g）'2CeO2 （s）+2S（g）.The main component of desulfurization was CeO2 after regeneration, and without sulfate generation, the regeneration exhaust were mainly SO2 and a small amount of elemental sulfur. Between 500℃ and 800℃, increasing the temperature, the elemental sulfur production decreased and the regeneration ratio increased, the maximum was 96%. The regeneration temperature under O2 atmosphere should above 500℃. The O2 concentration was between 1% and 4%, increasing O2 concentration, the elemental sulfur production decreased and regeneration ratio increased. Between 500 ℃ and 800℃, O2 concentration was 1-4%, the optimum regeneration conditions which elemental sulfur production was maximum were:700℃,1% O2. The chemical reaction and diffusion reaction kinetics equations of cerium oxide high temperature coal gas desulfurizer under O2 atmosphere were: dx/dt=0.102×103e-18544/8.314×CCO21.032（1-x）0.391 （chemical reaction） dx/dt=1.46×103e-37800/8.314×TCO21.074（1-x）0.5533 （diffusion reaction）The regeneration of cerium oxide high temperature coal gas desulfurization under SO2 atmosphere, the reaction was:Ce2O2S（s）+SO2（g）'2CeO2（s）+2S（g）.The main component of desulfurization sorbent was CeO2 after regeneration, and without sulfate generation, the main regeneration exhaust was elemental sulfur. Increasing temperature or SO2 concentration, the elemental sulfur production and regeneration ratio all increased. Between 600℃ and 750℃, the SO2 concentration was 0.81-4.25%, the optimum regeneration condition which elemental sulfur production was maximum were:750℃,4.25% SO2. The chemical reaction and diffusion reaction kinetics equations of cerium oxide high temperature coal gas desulfurization under SO2 atmosphere were: dx/dt=0.902×103e-41733/8.314×TCSO20.9698（1-x）0.6046 （chemical reaction） dx/dt=14.157×103 e-66111/8.314×TCSO20.9374 （1-x）0.6292 （diffusion reaction）The regeneration of cerium oxide high temperature coal gas desulfurizer under SO2-O2 atmosphere, the reactions were: Ce2O2S（s）+2O2（g）' 2CeO2 （s）+SO2 （g） （main） Ce2O2S（s）+SO2（g）'2CeO2（s）+2S（g） （main） S（g）+O2（g）'SO2（g）.The main component of desulfurization sorbent was CeO2 after regeneration, the regeneration exhaust were SO2 and elemental sulfur. Increasing temperature, the regeneration ratio and elemental sulfur production increased. The regeneration gas flow increasing, the elemental sulfur production and regeneration ratio increased at first and then decreased. The CS02/CO2 increased, the regeneration ratio changed little, but the elemental sulfur production increased.The form of elemental sulfur was S which cerium oxide high temperature coal gas desulfurizer regeneration under O2 atmosphere, SO2 atmosphere, SO2-O2 atmosphere. |
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