| The new process of benzene one-step oxidation to phenol with N2O over Fe-ZSM-5zeolite is good for efficient production of phenol while facilitating the removal of N2O in industrial emissions, this new process is a win-win project about economic development and environmental friendly. Research of this process focused on the catalyst R&D currently, the Fe-ZSM-5zeolite, as a catalyst, has excellent initial catalytic activity in this reaction and good performance in regeneration, but the problem of rapid deactivation is the main obstacle in the slow process of industrialization. Based on the past research, this article studied on the effective operating range of reaction and regeneration conditions, and matching scheme of reaction-regeneration. Hope to lay the foundation for matching and coupling technology of reaction-regeneration in ultimate industrial production of phenol.Experiments of study on reaction conditions were investigated by single factor test method and were operating in a integral tubular reactor(<D16x2mm, L=400mm) on fixed-bed, experimented and compared the effects of reaction temperatures, space velocity, molar ratios of benzene:N2O on performance of Fe-ZSM-5zeolite. Range of optimum operating conditions of reaction were determined as follows:reaction temperature of400℃-450℃, space velocity of4000h-1-5000h-1, benzene:N2O of6:1-10:1. Under such conditions, the yield of phenol is relatively higher, up to77.8%, effective operating range of Fe-ZSM-5zeolite is120min. Experiments of study on regeneration conditions of Fe-ZSM-5zeolite were investigated by single factor test method and were operating in a integral tubular reactor(φ16×2mm, L=400mm) on fixed-bed, experimented and compared the effects of regeneration temperatures, regeneration time, space velocity of regeneration gas, and molar ratios of N2O in regeneration gas on regeneration performance of Fe-ZSM-5zeolite. Range of optimum operating conditions of regeneration were determined as follows:regeneration temperature of400℃-450℃, regeneration time of20-40min, regeneration space velocity of4000h-1-6500h-1, molar ratio of N2O of10%-12.5%. Under such regeneration conditions, Fe-ZSM-5zeolite could be restored to the performance as fresh catalyst.Consider the reaction and regeneration as an organic whole in process analysis, the Fe-ZSM-5zeolite prepared here has two time operating ranges, one is the initial activity time domain in the first40min in reaction, which has high activity, another one is stable active time domain in40min-120min. The optimum matching conditions of reaction and regeneration were determined as follows:reaction temperature425℃-445℃, regeneration temperature400℃-470℃, space velocity of4500h-1,benzene:N2O=8:1, N2O ratio of10%in regeneration gas; Compare and discuss the fixed bed technology, moving bed technology and circulating fluidized bed technology in matching scheme of reaction-regeneration of N2O oxidation of benzene to phenol over Fe-ZSM-5zeolite. |
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