Experimental Study and Modeling of an Adiabatic Fixed-bed Reactor for Methanol Dehydration to Dimethyl Ether

2009 ◽  
Vol 17 (4) ◽  
pp. 630-634 ◽  
Author(s):  
M. Fazlollahnejad ◽  
M. Taghizadeh ◽  
A. Eliassi ◽  
G. Bakeri
Keyword(s):  
Experimental Study ◽  
Dimethyl Ether ◽  
Fixed Bed ◽  
Fixed Bed Reactor ◽  
Methanol Dehydration

Dimethyl Ether Synthesis via Methanol Dehydration over BEA Zeolite from Bagasse Fly Ash with Zircronium- and Nickel-Ion Exchange

2014 ◽  
Vol 931-932 ◽  
pp. 3-6 ◽  
Author(s):  
Watcharakorn Pranee ◽  
Pornsawan Assawasaengrat ◽  
Arthit Neramittagapong ◽  
Sasitorn Intarachit ◽  
Sutasinee Neramittagapong
Keyword(s):  
Fly Ash ◽  
Dimethyl Ether ◽  
Fixed Bed ◽  
Fixed Bed Reactor ◽  
Beta Zeolite ◽  
Methanol Dehydration ◽  
Nickel Ion ◽  
Bagasse Fly Ash ◽  
Bea Zeolite ◽  
Dimethyl Ether Synthesis

The synthesis of dimethyl ether via methanol dehydration has been carried out over Beta zeolite (BEA) and ion-exchanged Beta zeolite from bagasse fly ash using hydrothermal method. The reactions were taken place in a fixed-bed reactor. The effects of nickel and zirconium ion-exchanged of BEA were investigated. Ni-BEA zeolite exhibited high methanol conversion rate and DME-resultant upon the reaction temperature from 200 to 225°C with equilibrium-limiting condition over 225°C; Furthermore, the Ni-BEA zeolite presented the best stable activity at 225°C over 1,200 minute. The Ni-BEA zeolite has also been interesting as a zeolite which suited to be one role importance to improve the properties for methanol dehydration to dimethyl ether.

Dimethyl Ether Synthesis via Methanol Dehydration over Diatomite Catalyst Modified Using Hydrochloric Acid

2014 ◽  
Vol 931-932 ◽  
pp. 42-46 ◽  
Author(s):  
Watcharakorn Pranee ◽  
Pornsawan Assawasaengrat ◽  
Arthit Neramittagapong ◽  
Sutasinee Neramittagapong
Keyword(s):  
Hydrochloric Acid ◽  
Dimethyl Ether ◽  
Active Sites ◽  
Fixed Bed ◽  
Methanol Conversion ◽  
Catalytic Performance ◽  
Fixed Bed Reactor ◽  
Methanol Dehydration ◽  
Dimethyl Ether Synthesis ◽  
Ether Synthesis

The synthesis of dimethyl ether via methanol dehydration has been carried out over untreated-diatomite catalyst (DM) and hydrochloric acid modified treatment on diatomite catalyst (DMHC). The reactions were carried out in a fixed-bed reactor. The effects of hydrochloric acid modifications of diatomite on its catalytic performance were studied. The characterization such as XRD, SEM, FT-IR and FT-Raman had no deformation after HCl-modified treatment on catalysts. DMHC catalyst apparently gave the higher methanol conversion rate than DM due to the acidity while the selectivity of dimethyl ether from 250 to 350°C was slightly changed. The acidity was depended upon Al(IV) ions; nevertheless, both Al(V) and Al(VI) were affected and hence increasing the basic active sites. Not only was the competitively catalytic methanol dehydrogenation preferred with basic condition but also methanol-blocking water molecule interaction was the unwanted reaction. In this investigation, the chemical-bond arrangements of silicon and aluminium ions were proposed with solid MAS/NMR. The DMHC catalyst exhibited better DME yield than the DM catalyst, and it could be used as a selective catalyst for DME synthesis from methanol.

Synthesis and Characterization of Different γ-Al2O3 Nanocatalysts for Methanol Dehydration to Dimethyl Ether

2012 ◽  
Vol 10 (1) ◽  
Author(s):  
Seyyed Ya'ghoob Hosseini ◽  
Mohammad Reza Khosravi Nikou
Keyword(s):  
Dimethyl Ether ◽  
Solid Acid Catalyst ◽  
Fixed Bed ◽  
Operating Parameter ◽  
Textural Properties ◽  
Ammonia Solution ◽  
Precipitation Method ◽  
High Yield ◽  
Methanol Dehydration ◽  
Adsorption Desorption

Abstract A simple co-precipitation method was utilized to synthesize γ-Al2O3 catalysts using aluminum nitrate nonahydrate as the source of aluminum cations for methanol dehydration to dimethyl ether (DME). Different precipitating agents comprising ammonium carbonate, ammonium bicarbonate and ammonia solutions were used for preparation of the samples. The catalysts were characterized by XRD, FTIR, SEM, NH3-TPD and N2 adsorption-desorption techniques. The sample prepared by ammonia solution had the highest acidity among the synthesized catalysts. Also, N2 adsorption-desorption results showed suitable textural properties for all of the synthesized samples. Vapor phase dehydration of methanol to DME was performed in the fixed bed micro reactor over the synthesized catalysts and commercial one for comparison purposes. The effects of different characteristics of catalysts such as surface area, acidity, sintering factor and temperature as an operating parameter on performance of catalysts were investigated. The catalyst prepared by ammonia solution showed best catalytic activity due to the suitable textural properties and high amount of acidic sites. Also, the results showed that only high acid strength can’t result high yield of DME for a solid acid catalyst.

Dimethyl Ether Conversion to Olefins over the SAPO-34/ZrO2 Catalysts: Effect of the ZrO2 Supporter

2011 ◽  
Vol 347-353 ◽  
pp. 3681-3684 ◽  
Author(s):  
Young Ho Kim ◽  
Su Gyung Lee ◽  
Byoung Kwan Yoo ◽  
Han Sol Je ◽  
Chu Sik Park
Keyword(s):  
Physicochemical Properties ◽  
Dimethyl Ether ◽  
Fixed Bed ◽  
Fixed Bed Reactor ◽  
Coke Deposition ◽  
Light Olefins ◽  
Similar Activity ◽  
Dimethyl Ether Conversion ◽  
Zro2 Catalyst ◽  
Catalyst Lifetime

A SAPO-34 catalyst is well known to be one of the best catalysts for DME to olefins (DTO) reaction. Main products of the reaction were light olefins such as ethylene, propylene and butenes. However, the main problem is rapid deactivation of the SAPO-34 catalyst due to coke deposition during DTO reaction. In this study, various SAPO-34/ZrO2 catalysts added with ZrO2 were prepared for improving the lifetime and their physicochemical properties have been characterized by XRD and SEM. The DTO reaction over various SAPO-34/ZrO2 catalysts was carried out using a fixed bed reactor. All SAPO-34/ZrO2 catalysts showed similar activity and selectivity in the DTO reaction. The SAPO-34(9wt%)/ZrO2 catalyst was showed the best performance for the catalyst lifetime.

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