Controlled Nanostructure of Zeolite Crystal Encapsulating FeMnK Catalysts Targeting Light Olefins from Syngas

2020 ◽  
Vol 12 (52) ◽  
pp. 57950-57962
Author(s):  
Can Zhu ◽  
Mingwei Zhang ◽  
Chao Huang ◽  
Yizhuo Han ◽  
Kegong Fang
Keyword(s):  
Light Olefins ◽  
Zeolite Crystal

Structural/Texture Evolution During Facile Substitution of Ni into ZSM-5 Nanostructure vs. its Impregnation Dispersion Used in Selective Transformation of Methanol to Ethylene and Propylene

2020 ◽  
Vol 23 ◽  
Author(s):  
Parisa Sadeghpour ◽  
Mohammad Haghighi ◽  
Mehrdad Esmaeili
Keyword(s):  
High Temperature ◽  
Physicochemical Properties ◽  
Active Sites ◽  
Catalytic Performance ◽  
Fixed Bed Reactor ◽  
Light Olefins ◽  
Isomorphous Substitution ◽  
Impregnation Method ◽  
Hydrothermal Temperature ◽  
X Ray

Aim and Objective: Effect of two different modification methods for introducing Ni into ZSM-5 framework was investigated under high temperature synthesis conditions. The nickel successfully introduced into the MFI structures at different crystallization conditions to enhance the physicochemical properties and catalytic performance. Materials and Methods: A series of impregnated Ni/ZSM-5 and isomorphous substituted NiZSM-5 nanostructure catalysts were prepared hydrothermally at different high temperatures and within short times. X-ray diffraction (XRD), Field emission scanning electron microscopy (FESEM), Energy dispersive X-ray (EDX), Brunner, Emmett and Teller-Barrett, Joyner and Halenda (BET-BJH), Fourier transform infrared (FTIR) and Temperature-programmed desorption of ammonia (TPDNH3) were applied to investigate the physicochemical properties. Results: Although all the catalysts showed pure silica MFI–type nanosheets and coffin-like morphology, using the isomorphous substitution for Ni incorporation into the ZSM-5 framework led to the formation of materials with lower crystallinity, higher pore volume and stronger acidity compared to using impregnation method. Moreover, it was found that raising the hydrothermal temperature increased the crystallinity and enhanced more uniform incorporation of Ni atoms in the crystalline structure of catalysts. TPD-NH3 analysis demonstrated that high crystallization temperature and short crystallization time of NiZSM-5(350-0.5) resulted in fewer weak acid sites and medium acid strength. The MTO catalytic performance was tested in a fixed bed reactor at 460ºC and GHSV=10500 cm3 /gcat.h. A slightly different reaction pathway was proposed for the production of light olefins over impregnated Ni/ZSM-5 catalysts based on the role of NiO species. The enhanced methanol conversion for isomorphous substituted NiZSM-5 catalysts could be related to the most accessible active sites located inside the pores. Conclusion: The impregnated Ni/ZSM-5 catalyst prepared at low hydrothermal temperature showed the best catalytic performance, while the isomorphous substituted NiZSM-5 prepared at high temperature was found to be the active molecular sieve regarding the stability performance.

Efficient Production of Light Olefin Based on Methanol Dehydration: Simulation and Design Improvement

2020 ◽  
Vol 23 ◽  
Author(s):  
S. Majid Abdoli ◽  
Mahsa Kianinia
Keyword(s):  
Dimethyl Ether ◽  
Flow Reactor ◽  
New Technology ◽  
Plug Flow ◽  
Light Olefins ◽  
Efficient Production ◽  
Actual Process ◽  
Light Olefin ◽  
Aspen Hysys ◽  
Improved Design

Background: Ethylene, propylene, and butylene as light olefins are the most important intermediates in the petrochemical industry worldwide. Methanol to olefins (MTO) process is a new technology based on catalytic cracking to produce ethylene and propylene from methanol. Aims and Objective: This study aims to simulate the process of producing ethylene from methanol by using Aspen HYSYS software from the initial design to the improved design. Methods: Ethylene is produced in a two-step reaction. In an equilibrium reactor, the methanol is converted to dimethyl ether by an equilibrium reaction. The conversion of the produced dimethyl ether to ethylene is done in a conversion reactor. Changes have been made to improve the conditions and get closer to the actual process design done in the industry. The plug flow reactor has been replaced by the equilibrium reactor, and the distillation column was employed to separate the dimethyl ether produced from the reactor. Result and Conclusion: The effect of the various parameters on the ethylene production was investigated. Eventually, ethylene is

Life Time Improvement of Hierarchically Structured SAPO-34 Nanocatalyst in MTO Reaction via Applying Clinoptilolite, Investigating of Composite Design via RSM

2020 ◽  
Vol 23 ◽  
Author(s):  
Reza Yazdanpanah ◽  
Eshagh Moradiyan ◽  
Rouein Halladj ◽  
Sima Askari
Keyword(s):  
Surface Area ◽  
Natural Zeolite ◽  
Coke Formation ◽  
Life Time ◽  
Weight Percent ◽  
Light Olefins ◽  
Bet Surface Area ◽  
Relative Crystallinity ◽  
Mto Reaction ◽  
The Common

Aim and Objective: The research focuses on recent progress in the production of light olefins. Hence, the common catalyst of the reaction (SAPO-34) deactivates quickly because of coke formation, we reorganized the mechanism combining SAPO-34 with a natural zeolite in order to delay the deactivation time. Materials and Methods: The synthesis of nanocomposite catalyst was conducted hydrothermally using experimental design. Firstly, Clinoptilolite was modified using nitric acid in order to achieve nano scaled material. Then, the initial gel of the SAPO-34 was prepared using DEA, aluminum isopropoxide, phosphoric acid and TEOS as the organic template, sources of Aluminum, Phosphor, and Silicate, respectively. Finally, the modified zeolite was combined with SAPO-34's gel. Results: 20 different catalysts due to D-Optimal design were synthesized and the nanocomposite with 50 weight percent of SAPO-34, 4 hours Crystallization and early Clinoptilolite precipitation showed the highest relative crystallinity, partly high BET surface area and hierarchical structure. Conclusion: Different analysis illustrated the existence of both components. The most important property alteration of nanocomposite was the increment of pore mean diameters and reduction in pore volumes in comparison with free SAPO-34. Due to low price of Clinoptilolite, the new catalyst develops the economy of the process. Using this composite, according to formation of multi-sized pores located hierarchically on the surface of the catalyst and increased surface area, significant amounts of Ethylene and Propylene, in comparison with free SAPO-34, were produced, as well as deactivation time that was improved.

Nano-Structured Ceramic Oxide Catalyst for Syn Gas Conversion to Light Olefins

2012 ◽  
Vol 1 (1) ◽  
pp. 24-31
Author(s):  
Syed Tajammul Hussain ◽  
Nisar Ahmad ◽  
Bakhtiar Muhammad
Keyword(s):  
Oxide Catalyst ◽  
Light Olefins ◽  
Ceramic Oxide ◽  
Gas Conversion

Synthesis of composite zeolites composed of SAPO-5 and SAPO-34 and its application in methanol dehydration to light olefins

2021 ◽  
Author(s):  
Yadong Bai ◽  
Qinghu Zeng ◽  
Jinghui Sun ◽  
Qingfeng Song ◽  
Lei Tang ◽  
...  
Keyword(s):  
Light Olefins ◽  
Methanol Dehydration

scholarly journals Fischer–Tropsch Synthesis for Light Olefins from Syngas: A Review of Catalyst Development

Reactions ◽  
2021 ◽  
Vol 2 (3) ◽  
pp. 227-257
Author(s):  
Arash Yahyazadeh ◽  
Ajay K. Dalai ◽  
Wenping Ma ◽  
Lifeng Zhang
Keyword(s):  
Pore Size ◽  
Crystal Size ◽  
Tropsch Synthesis ◽  
Light Olefins ◽  
Face Centered Cubic ◽  
Fischer Tropsch ◽  
Light Olefin ◽  
Structure Transition ◽  
Fischer Tropsch Synthesis ◽  
Olefin Selectivity

Light olefins as one the most important building blocks in chemical industry can be produced via Fischer–Tropsch synthesis (FTS) from syngas. FT synthesis conducted at high temperature would lead to light paraffins, carbon dioxide, methane, and C5+ longer chain hydrocarbons. The present work focuses on providing a critical review on the light olefin production using Fischer–Tropsch synthesis. The effects of metals, promoters and supports as the most influential parameters on the catalytic performance of catalysts are discussed meticulously. Fe and Co as the main active metals in FT catalysts are investigated in terms of pore size, crystal size, and crystal phase for obtaining desirable light olefin selectivity. Larger pore size of Fe-based catalysts is suggested to increase olefin selectivity via suppressing 1-olefin readsorption and secondary reactions. Iron carbide as the most probable phase of Fe-based catalysts is proposed for light olefin generation via FTS. Smaller crystal size of Co active metal leads to higher olefin selectivity. Hexagonal close-packed (HCP) structure of Co has higher FTS activity than face-centered cubic (FCC) structure. Transition from Co to Co3C is mainly proposed for formation of light olefins over Co-based catalysts. Moreover, various catalysts’ deactivation routes are reviewed. Additionally, techno-economic assessment of FTS plants in terms of different costs including capital expenditure and minimum fuel selling price are presented based on the most recent literature. Finally, the potential for global environmental impacts associated with FTS plants including atmospheric and toxicological impacts is considered via lifecycle assessment (LCA).

scholarly journals Utilization of SAPO-18 or SAPO-35 in the bifunctional catalyst for the direct conversion of syngas to light olefins

RSC Advances ◽  
2021 ◽  
Vol 11 (23) ◽  
pp. 13876-13884
Author(s):  
Yuxuan Huang ◽  
Hongfang Ma ◽  
Zhiqiang Xu ◽  
Weixin Qian ◽  
Haitao Zhang ◽  
...  
Keyword(s):  
Direct Conversion ◽  
Bifunctional Catalyst ◽  
Light Olefins

SAPO-18 and SAPO-35 were synthesized and utilized as the zeotype in the bifunctional catalyst for the STO process, respectively.

scholarly journals Control of zeolite microenvironment for propene synthesis from methanol

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Longfei Lin ◽  
Mengtian Fan ◽  
Alena M. Sheveleva ◽  
Xue Han ◽  
Zhimou Tang ◽  
...  
Keyword(s):  
Active Sites ◽  
Inelastic Neutron Scattering ◽  
Sustainable Manufacturing ◽  
Methanol Conversion ◽  
Acid Sites ◽  
Light Olefins ◽  
Carbon Bond ◽  
X Ray ◽  
Carbon Carbon Bond ◽  
Catalytic Stability

AbstractOptimising the balance between propene selectivity, propene/ethene ratio and catalytic stability and unravelling the explicit mechanism on formation of the first carbon–carbon bond are challenging goals of great importance in state-of-the-art methanol-to-olefin (MTO) research. We report a strategy to finely control the nature of active sites within the pores of commercial MFI-zeolites by incorporating tantalum(V) and aluminium(III) centres into the framework. The resultant TaAlS-1 zeolite exhibits simultaneously remarkable propene selectivity (51%), propene/ethene ratio (8.3) and catalytic stability (>50 h) at full methanol conversion. In situ synchrotron X-ray powder diffraction, X-ray absorption spectroscopy and inelastic neutron scattering coupled with DFT calculations reveal that the first carbon–carbon bond is formed between an activated methanol molecule and a trimethyloxonium intermediate. The unprecedented cooperativity between tantalum(V) and Brønsted acid sites creates an optimal microenvironment for efficient conversion of methanol and thus greatly promotes the application of zeolites in the sustainable manufacturing of light olefins.

Kinetics of Oxidative Cracking of n‐Hexane to Light Olefins using Lattice Oxygen of a VO x /SrO‐γAl 2 O 3 Catalyst

2021 ◽  
Author(s):  
Hussein K. Amusa ◽  
Sagir Adamu ◽  
Abeer S. Arjah ◽  
Saad A. Al‐Bogami ◽  
Sameer Al‐Ghamdi ◽  
...  
Keyword(s):  
Lattice Oxygen ◽  
Light Olefins ◽  
Oxidative Cracking ◽  
Kinetics Of
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