Mechanism transformation of cyclohexene-thiophene competitive adsorption in FAU zeolite

来源 :中国化学工程学报(英文版) | 被引量 : 0次 | 上传用户:chyenu
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
Competition of hydrocarbon compounds with sulfides in gasoline has caused a not very high selectivity of sulfides in adsorption desulfurization so far,resulting in a reduction of catalyst lifetime as well as more sulfur oxide emissions.Tostudy the whole competitive process changing with the increase of the loading,the dynamic competition adsorption mechanism of cyclohexene and thiophene in siliceous faujasite(FAU) zeolite was analyzed by the Monte Carlo simulation.The results showed that with the increase of the loading,thiophene and cyclohexene had different performances before and after the inflection point of 40 molecule/UC.The adsorbates were distributed ideally at optimal sites during the stage that occurred before the inflection point,which is called the “optimal-displacement adsorption” stage.When approaching the inflection point,the competition became apparent and the displacement appeared accordingly,some thiophene molecules at S sites (refers to the sites inside the supercages) were displaced by cyclohexene.After the inflection point,the concentration of adsorbates at W sites (refers to the 12-membered ring connecting the supercages) was significantly reduced,whereas the adsorbates at S sites got more concentrated.The stage some cyclohexene molecules displaced by thiophene and inserted into the center of the supercage can be named as the “insertion-displacement adsorption” stage,and both the adsorption behavior and the competitive relationship became localized when the adsorption amount became saturated.This shift in the competitive adsorption mechanism was due to the sharp increase of interac-tion energy between the adsorhates.Besides,the increase in temperature and ratio of Si/Al will allow the adsorbates,especially thiophene molecules to occupy more adsorption sites,and it is beneficial to improve the desulfurization selectivity.
其他文献
近年来,随着我国的经济发展逐渐走向“新常态”,国民经济不断向高质量发展,经济增速放缓,产业结构优化成为了经济发展的重要动力。而在整个国民经济体系中,交通运输一直以其广泛的产业关联性,不断推动着地区间经济的协调发展。然而,交通运输在为我国成就的经济奇迹做出了巨大贡献的同时也带来了许多负面影响,如石油、天然气等不可再生能源的急剧消耗,生态环境污染等。为了找出一条和外部环境协调共生的交通发展道路,可持续
With the annual increase in the amount of lithium-ion batteries (LIBs),the development of spent LIBs recycling technology has gradually attracted attention.Graphite is one of the most critical materials for LIBs,which is listed as a key energy source by m
The particle size distribution of polymer always develops in emulsion polymerization systems,and cer-tain key phenomena/mechanisms as well as properties of the final product are significantly affected by this distribution.This review mainly focuses on the
近几年来,无人驾驶汽车发展迅速,自动泊车系统作为无人驾驶车辆最后一环,受到了人们的广泛重视。自动泊车系统对于缓解交通困难,提高交通效率,降低泊车事故具有重要意义。本文结合各方面研究现状,从路径规划、路径优化和路径跟踪三个方面对平行泊车系统进行研究,主要工作内容如下:1、基于阿克曼转向基础,建立了低速状态下的泊车运动学模型。在Simulink中搭建了仿真模型,在相同车辆参数和输入条件的前提下,对Si
The mass transfer of Rhodamine 6G from the droplet to the continuous phase in a coaxial micro-channel is studied using micro-LIF (Laser-Induced Fluorescence).The mass distribution inside droplet is measured and visualized.The experimental results affirm t
Distillation is the most common separation technology utilized in the petroleum and chemistry indus-tries.Due to the wide usage of the distillation column,even a small improvement in performance may result in significant energy cost savings.Aiming to impr
The development of an inorganic electrochemical stable solid-state electrolyte is essentially responsible for future state-of-the-art all-solid-state lithium batteries (ASSLBs).Because of their advantages in safety,working temperature,high energy density,
In the process of membrane absorption,spontaneous wetting of hydrophobic microporous membrane causes membrane modification and increases membrane phase mass transfer resistance,which have attracted wide interest.However,due to the limitations of previous
本文以西安市主城区地下水为研究对象,在资料收集、野外调查、水文地质补充调查基础上,应用水文地球化学、统计学以及地下水水质与水污染评价等理论方法,在时空上系统研究了地下水水化学特征以及地下水污染分布情况,并通过水质与水污染评价对地下水污染情况进行深入分析。揭示了人类活动影响下的地下水水质演化过程,阐明研究区地下水主要污染途径与来源,为西安市开展地下水环境保护工作提供科技支撑。主要研究成果如下:(1)
国民经济的健康快速发展促使我国在世界经济发展中突显大国担当,不断塑造先锋角色。我国许多建设企业不断加大对外基础设施的建设项目投资,许多非洲国家抓住这个机遇不断加大公路建设投资力度。由于红土粒料在西非众多国家大量分布,具有强度高,稳定性强的特点,广泛应用于非洲许多国家公路建设工程路面结构中,但是由于科特迪瓦奥迭内至马里边境公路现状道路尚未有完整合理的路面结构,所以本文以科特迪瓦奥迭内至马里边境公路建