METHANOL CONVERSION TO OLEFINS OVER HIGH-SILICA ZEOLITES IN CONTINUOUS FLOW FIXED-BED REACTOR

1997 ◽  
Vol 15 (1-2) ◽  
pp. 19-36 ◽  
Author(s):  
D. S. Redwan
Keyword(s):  
Continuous Flow ◽  
Fixed Bed ◽  
Methanol Conversion ◽  
Fixed Bed Reactor ◽  
High Silica ◽  
High Silica Zeolites

Design of a continuous flow immobilized-cell reactor for biosynthetical production of L-aspartic acid

1985 ◽  
Vol 50 (10) ◽  
pp. 2122-2133 ◽  
Author(s):  
Jindřich Zahradník ◽  
Marie Fialová ◽  
Jan Škoda ◽  
Helena Škodová
Keyword(s):  
Aspartic Acid ◽  
Continuous Flow ◽  
Immobilized Cells ◽  
Scale Up ◽  
Fixed Bed ◽  
Packed Bed ◽  
Fixed Bed Reactor ◽  
Experimental Program ◽  
Design Parameters ◽  
Immobilized Cell

An experimental study was carried out aimed at establishing a data base for an optimum design of a continuous flow fixed-bed reactor for biotransformation of ammonium fumarate to L-aspartic acid catalyzed by immobilized cells of the strain Escherichia alcalescens dispar group. The experimental program included studies of the effect of reactor geometry, catalytic particle size, and packed bed arrangement on reactor hydrodynamics and on the rate of substrate conversion. An expression for the effective reaction rate was derived including the effect of mass transfer and conditions of the safe conversion-data scale-up were defined. Suggestions for the design of a pilot plant reactor (100 t/year) were formulated and decisive design parameters of such reactor were estimated for several variants of problem formulation.

scholarly journals Hierarchical H-ZSM5 zeolites based on natural kaolinite as a high-performance catalyst for methanol to aromatic hydrocarbons conversion

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Ahmad Asghari ◽  
Mohammadreza Khanmohammadi Khorrami ◽  
Sayed Habib Kazemi
Keyword(s):  
Pore Size ◽  
Aromatic Hydrocarbons ◽  
High Performance ◽  
Low Cost ◽  
Direct Synthesis ◽  
Fixed Bed ◽  
Methanol Conversion ◽  
Catalytic Performance ◽  
Fixed Bed Reactor ◽  
Good Prospect

AbstractThe present work introduces a good prospect for the development of hierarchical catalysts with excellent catalytic performance in the methanol to aromatic hydrocarbons conversion (MTA) process. Hierarchical H-ZSM5 zeolites, with a tailored pore size and different Si/Al ratios, were synthesized directly using natural kaolin clay as a low-cost silica and aluminium resource. Further explored for the direct synthesis of hierarchical HZSM-5 structures was the steam assisted conversion (SAC) with a cost-effective and green affordable saccharide source of high fructose corn syrup (HFCS), as a secondary mesopore agent. The fabricated zeolites exhibiting good crystallinity, 2D and 3D nanostructures, high specific surface area, tailored pore size, and tunable acidity. Finally, the catalyst performance in the conversion of methanol to aromatic hydrocarbons was tested in a fixed bed reactor. The synthesized H-ZSM5 catalysts exhibited superior methanol conversion (over 100 h up to 90%) and selectivity (over 85%) in the methanol conversion to aromatic hydrocarbon products.

scholarly journals Hierarchical Low Si/Al Ratio Ferrierite Zeolite by Sequential Postsynthesis Treatment: Catalytic Assessment in Dehydration Reaction of Methanol

2019 ◽  
Vol 2019 ◽  
pp. 1-9 ◽  
Author(s):  
Enrico Catizzone ◽  
Massimo Migliori ◽  
Alfredo Aloise ◽  
Rossella Lamberti ◽  
Girolamo Giordano
Keyword(s):  
Textural Properties ◽  
Vapour Phase ◽  
Solution Concentration ◽  
Methanol Conversion ◽  
Molar Ratio ◽  
Light Hydrocarbons ◽  
Hierarchical Zeolites ◽  
Type Zeolite ◽  
High Silica ◽  
High Silica Zeolites

In contrast to high silica zeolites, it is difficult to obtain mesoporosity in zeolites with low Si/Al ratio (e.g., <20) via conventional NaOH-based treatment, making the obtainment of hierarchical zeolites with high acidity a challenging target. In this paper, we report the preparation of hierarchical FER-type zeolite at low Si/Al molar ratio (about 10) by postsynthesis etching involving a sequence of three treatments with NaAlO2, HCl, and NaOH solutions and investigate the effect of both NaAlO2 solution concentration and time of treatment on the textural properties. The obtained materials exhibit a mesoporous volume higher than the parent ferrierite with no significant effect on the sample acidity. The catalytic activity of some samples was investigated in vapour-phase methanol dehydration to dimethyl ether, revealing the superiority of hierarchical zeolites in terms of methanol conversion, although the presence of mesopores causes formation of light hydrocarbons at high temperatures.

Paths of methanol conversion to hydrocarbons on high-silica zeolites

1985 ◽  
Vol 34 (11) ◽  
pp. 2251-2257
Author(s):  
T. V. Vasina ◽  
E. G. Khelkovskaya-Sergeeva ◽  
B. K. Nefedov ◽  
O. V. Bragin
Keyword(s):  
Methanol Conversion ◽  
High Silica ◽  
High Silica Zeolites

Modeling and Optimization of MeOH to DME in Isothermal Fixed-bed Reactor

2010 ◽  
Vol 8 (1) ◽  
Author(s):  
Mohammad Farsi ◽  
Abdolhossein Jahanmiri ◽  
Reza Eslamloueyan
Keyword(s):  
Fixed Bed ◽  
Methanol Conversion ◽  
Fixed Bed Reactor ◽  
Methanol Dehydration ◽  
Algebraic Equations ◽  
Optimal Temperature ◽  
Heterogeneous Model ◽  
One Dimensional ◽  
Shell And Tube ◽  
Green Fuel

Dimethyl ether (DME) is a green fuel that commercially produced in an adiabatic fixed bed reactor by methanol dehydration. In the present work, a shell and tube fixed bed reactor is modeled and optimized for DME production. The reactor is modeled based on mass and energy conservation equations as well as auxiliary equations. In order to estimate the DME production and temperature profile along the reactor, a one dimensional heterogeneous model consist of a set of nonlinear differential and algebraic equations has been solved numerically. Also, The DME production in the isothermal reactor is maximized by adjusting the optimal temperature distribution along the reactor using genetic algorithm. Then, the performance of the proposed isothermal reactor is compared with industrial adiabatic fixed bed reactor. Results showed the higher DME production rate and methanol conversion in the optimized reactor.

Effect of Silica Base Catalyst on Transformation of Methanol to Hydrocarbon

2017 ◽  
Vol 751 ◽  
pp. 512-517 ◽  
Author(s):  
Supranee Lao-Ubol ◽  
Phunthinee Somwongsa ◽  
Pracha Laoauyporn ◽  
Pasinee Panith ◽  
Siriporn Larpkiattaworn ◽  
...  
Keyword(s):  
Pore Diameter ◽  
Fixed Bed ◽  
Methanol Conversion ◽  
Liquid Hydrocarbon ◽  
Product Distribution ◽  
Catalytic Performance ◽  
Zeolite Catalysts ◽  
Fixed Bed Reactor ◽  
Phosphorus Species ◽  
Methanol To Hydrocarbon

Five different types of silica catalyst (SBA-15, SBA-15-PO3H2, and three different Si/Al ratio of commercial zeolites (30, 80 and 280) were used to study the transformation of methanol to hydrocarbon (MTH). The aim of this study was to investigate the effect of pore diameter and acidity in the structure of silica catalysts on the process performances in terms of methanol conversion and hydrocarbon selectivity. The mesoporous silica catalysts were prepared by co-condensation method. The catalysts samples were characterized by GC-MS, XRD, BET, and NH3-TPD techniques. The catalytic performance of synthesized and commercial catalysts for MTH process was evaluated using a homemade fixed bed reactor at temperature (300°C). It was found that the liquid hydrocarbon product provided by zeolite catalysts is aromatic hydrocarbons-rich. High Si/Al zeolites with larger pore size lead to higher selectivity and yield to paraffins (C1-C7). In contrast to commercial zeolite catalyst, SBA-15 and its modification with phosphorus species showed no conversion under studied condition. These results indicate that both pore diameter and acidity influence the product distribution in methanol to hydrocarbon process.

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