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Effect of Metal Contamination on the Performance of Catalyst for Deep Catalytic Cracking Process
The effect of different metal contamination levels of catalysts for Deep Catalytic Cracking (DCC) on the distribu-tion and selectivity of DCC products was investigated in a FCC pilot unit. The pilot test results showed that the effects of the metal contamination level of catalyst on the propylene yield, the coke yield, the LPG yield, the gasoline yield, the selectivity of low carbon olefins, and coke selectivity was significant, and that the influence of metal contamination level on the conversion and dry gas yield was minor....
2020-11-11 22:33:38浏览:75
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Fe-modified HZSM-5 catalysts for ethanol conversion into light olefins
A series of Fe/HZSM-5 catalysts with different iron loadings were prepared by impregnation method.Characterization was performed by N2 adsorption-desorption,X-ray diffraction (XRD),NH3 temperature-programmed desorption (NH3-TPD),temperature-programmed reduction (TPR),temperature-programmed oxidation (TPO) and thermogravimetry (TG) analysis.Iron content in the synthesized samples varied from 1.1 wt% to 20 wt%.The obtained samples have been used for ethanol conversion into light olefins.It was found that the amount of strong acidity at 300-550 ℃ on Fe-modified samples was decreased,going with another new acid site appearance at 550-600 ℃ and that Fe/HZSM-5 catalysts were highly selective towards light olefins,especially the 9FZ sample.In addition,Fe-modified catalysts suppressed the conversion of ethanol to aromatics and paraffins and enhanced their anti-carbon deposit ability....
2020-10-22 17:35:41浏览:65
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Fe/SiO2纳米复合物上合成气制低碳烯烃催化性能研究
分别采用一步合成法和常规共沉淀法制备了 Fe/ SiO 2催化剂,通过 N2物理吸附、X 射线衍射、透射电镜、傅里叶变换红外光谱和程序升温还原等方法对催化剂进行了表征,并在固定床反应器中对其费托合成制低碳烯烃的催化性能进行了评价。结果表明,与共沉淀铁基催化剂不同,采用一步合成法制备的纳米复合物主要由 Fe3 O4相构成,形貌呈规则球形,平均粒径为30 nm,尺寸分布窄,更容易还原。一步合成法制得的 Fe/ SiO2催化剂对费托合成反应具有较高的活性和低碳烯烃选择性、较低的甲烷选择性和良好的稳定性。...
2020-10-22 17:35:41浏览:61
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合成气催化转化直接制备低碳烯烃研究进展
合成气直接催化转化制备低碳烯烃是C1化学与化工领域中一个极具挑战性的研究课题,具有流程短、能耗低等优势,已成为非石油路径生产烯烃的新途径。直接转化方式主要包括经由OX-ZEO双功能催化剂直接制低碳烯烃的双功能催化路线以及经由费托反应直接制备低碳烯烃的FTO路线。综述简述了近年来在合成气直接制备低碳烯烃方面的研究进展,重点讨论了低碳烯烃的形成机理、新型催化剂的研发及助剂对其催化性能的影响,并对合成气直接制烯烃的未来进行了展望。...
2020-10-02 20:35:09浏览:60
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合成气制低碳烯烃铁基催化剂制备研究现状
论述了合成气制低碳烯烃铁基催化剂的研究现状,并对未来的发展前景进行展望,以期为铁基催化剂的进一步研究提供参考。...
2020-10-02 20:35:09浏览:83
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合成气直接制低碳烯烃技术进展与经济性分析
合成气直接制低碳烯烃是近年来研究较多的石油替代路线合成重要有机化学品的工艺之一。本文对该工艺的技术进展,包括催化剂和工艺的开发情况进行了综述,认为高催化活性、高选择性催化剂是打破产品分布受ASF规律限制的关键,而反应器和新工艺的开发也可提高低碳烯烃的收率,减少CO2排放,并通过与其它成熟技术的组合,推进该工艺的工业化进程。由初步的技术经济性分析可见,与传统蒸汽裂解和经甲醇制烯烃工艺相比,合成气直接制低碳烯烃工艺具有较强的经济竞争力。...
2020-10-02 20:35:09浏览:52
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Progress in studies of natural gas conversion in China
Progress in natural gas conversion in China is presented in this paper, including processes of natural gas to synthesis gas (syngas), syngas to liquid hydrocarbons, oxygenates synthesis, methanol to olefins (MTO), methane to aromatics and oxidative coupling of methane (OCM)....
2020-09-13 23:35:02浏览:85
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Study on the deactivation and regeneration of the ZSM-5 catalyst used in methanol to olefins
ZSM-5 zeolite catalyst modified by a trace of metal cations shows high activity and high selectivity for the reaction of methanol to olefins (MTO), but it inclines to deactivate during the reaction. In this paper, the mechanism of the catalyst deactivation and the regeneration method were studied by X-ray diffraction (XRD), N2 adsorption-desorption, infrared spectra (IR), and infrared spectra coupled with NH3 molecular probes (IR-NH3). These characterizations indicated that coke formation was the main reason for the catalyst deactivation. To regenerate the deactivated catalyst, two methods, i.e., calcination and methanol leaching, were used. N2 adsorption-desorption, IR and IR-NH3 characterizations showed that both methods can eliminate coke deposited on the catalyst and make the catalyst reactivated. XRD showed that the structure of the catalyst did not change after regeneration. Interestingly, the regenerated catalyst even showed better catalytic performance of the MTO reaction than the fresh one. Besides, the calcination regeneration can eliminate coke more completely, however, the methanol leaching method can be more easily carried out in situ in the reactor....
2020-07-08 21:52:19浏览:71
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Study on Olefins Yield from Methanol Conversion over Different Catalysts
Conversion of Methanol to Olefins (MTO) under different reaction conditions was experimentally investigated over different catalysts, and comparison was made between the SAPO-34 and GOR-MLC catalysts. Optimization of reaction conditions has been explored. Conversion of methanol to olefins over these catalysts under different reaction temperatures was experimentally studied. In a fixed bed micro-reactor, the influence of temperature was found to be one of the major factors. For both catalysts the olefins yield was increased significantly when water was added to the methanol feed. A temperature range of 460-480 ℃ appeared to be the optimum range suitable for methanol conversion with appropriate catalyst activity and C2-C3 olefins yield. Some other hydrocarbons appeared during the MTO reaction in the presence of the SAPO-34 catalyst, while a lot of dimethylether was formed when the GOR-MLC catalyst was used. In the course of the MTO reaction, the GOR-MLC catalyst was found to have a faster catalyst deactivation rate compared to the SAPO-34 catalyst....
2020-07-08 21:52:19浏览:73
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Effects of Light Olefins Formation during Catalytic Pyrolysis of n-Heptane
The influence of zeolite structure and process parameters (including reaction temperature and catalyst/oil ratio)on rules for formation of ethylene and propylene in the course of catalytic pyrolysis of n-heptane was studied in a smallscale fixed fluid catalytic cracking unit.Test results have revealed that compared to the USY zeolite and Beta zeolite,the catalytic pyrolysis of n-heptane in the presence of the ZRP zeolite catalyst can result in higher yield and selectivity of ethylene and propylene,while a higher reaction temperature and a higher catalyst/oil ratio can promote the formation of ethylene and propylene during catalytic pyrolysis of n-heptane.The ethylene formation reaction is more sensitive to the changes in reaction temperature,whereas the changes in catalyst/oil ratio are more influential to the propylene formation reaction.This paper has made a preliminary exploration into the different reaction pathways for formation of ethylene and propylene on zeolites with different structures....
2020-07-08 21:52:19浏览:49
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甲醇制烯烃(MTO/MTP)技术研究进展
随着乙烯、丙烯等低碳烯烃供需矛盾的日益突出,针对我国“多煤少油少气”的能源现状,以煤或天然气为原料经甲醇制备低碳烯烃的技术越发重要。文章对甲醇制烯烃技术进展、反应机理和催化剂应用等进行了综述,并提出该技术下一步的改进方向。...
2020-06-12 16:09:56浏览:1598
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甲醇制烯烃(MTO/MTP)技术研究进展
随着乙烯、丙烯等低碳烯烃供需矛盾的日益突出,针对我国“多煤少油少气”的能源现状,以煤或天然气为原料经甲醇制备低碳烯烃的技术越发重要。文章对甲醇制烯烃技术进展、反应机理和催化剂应用等进行了综述,并提出该技术下一步的改进方向。...
2020-03-23 17:47:27浏览:1411
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SAPO-35分子筛的合成及其甲醇制烯烃反应性能
以六亚甲基亚胺为模板剂,采用水热法合成了不同硅含量的磷酸硅铝分子筛SAPO-35,并利用X射线衍射、X射线荧光光谱、扫描电镜、固体核磁、X射线光电子能谱和N2吸附-脱附等方法对样品进行了表征.研究了不同硅含量的SAPO-35分子筛在甲醇转化制烯烃反应中的催化行为,同时对比分析了具有相近硅含量的SAPO-35和SAPO-34分子筛在甲醇转化反应过程中积炭物种随反应时间的演变特征,尝试将分子筛结构和其积炭失活行为进行了关联....
2020-03-23 17:46:59浏览:1416
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煤基甲醇制烯烃技术及产业发展现状
介绍了煤基甲醇制烯烃技术及发展应用,指出煤基甲醇制烯烃是现代煤化工发展的新技术,也是今后发展的重要方向。我国在引进国外先进的甲醇制烯烃和甲醇制丙烯技术上,先后又自主开发了甲醇经二甲醚制低碳烯烃工艺、合成气经甲醇制低碳烯烃工艺和循环流化床甲醇制丙烯等技术,并逐步实现工业化应用。通过科学规划和优化产业结构,该技术在国内将会获得较好的发展。...
2020-03-23 17:42:42浏览:1427
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裂解C5烯烃醚化反应的开发与应用
综述了C5烯烃中异戊烯和环戊烯醚化反应的合成工艺以及甲基叔戊基醚和甲基环戊基醚的研究和发展前景.探讨混合C5中的异戊烯和环戊烯同时与甲醇发生醚化反应的可行性,提出通过改进甲基叔戊基醚合成的催化体系来促进C5中的异戊烯和环戊烯同时发生醚化反应,进而分离出高附加值产品甲基环戊基醚(CPME)和高辛烷值汽油组分甲基叔戊基醚(TAME),是裂解汽油副产C5馏分开发的重要方向....
2020-03-23 17:42:33浏览:1463
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