scholarly journals Thermodynamic Equilibrium Analysis of Methanol Conversion to Hydrocarbons Using Cantera Methodology

2012 ◽  
Vol 2012 ◽  
pp. 1-7 ◽  
Author(s):  
Duminda A. Gunawardena ◽  
Sandun D. Fernando
Keyword(s):  
Coke Formation ◽  
Equilibrium Composition ◽  
Abundant Species ◽  
Equilibrium Mixture ◽  
Methanol Conversion ◽  
Equilibrium Analysis ◽  
Ethyl Benzene ◽  
Aromatization Reaction ◽  
Pass Through ◽  
Methanol To Hydrocarbon

Reactions associated with removal of oxygen from oxygenates (deoxygenation) are an important aspect of hydrocarbon fuels production process from biorenewable substrates. Here we report the equilibrium composition of methanol-to-hydrocarbon system by minimizing the total Gibbs energy of the system using Cantera methodology. The system was treated as a mixture of 14 components which had CH3OH, C6H6, C7H8, C8H10 (ethyl benzene), C8H10 (xylenes), C2H4, C2H6, C3H6, CH4, H2O, C, CO2, CO, H2. The carbon in the equilibrium mixture was used as a measure of coke formation which causes deactivation of catalysts that are used in aromatization reaction(s). Equilibrium compositions of each species were analyzed for temperatures ranging from 300 to 1380 K and pressure at 0–15 atm gauge. It was observed that when the temperature increases the mole fractions of benzene, toluene, ethylbenzene, and xylene pass through a maximum around 1020 K. At 300 K the most abundant species in the system were CH4, CO2, and H2O with mole fractions 50%, 16.67%, and 33.33%, respectively. Similarly at high temperature (1380 K), the most abundant species in the system were H2 and CO with mole fractions 64.5% and 32.6% respectively. The pressure in the system shows a significant impact on the composition of species.

ON PRICE DYNAMICS WITH SEARCH AND BARGAINING IN THE PRODUCT MARKET

2020 ◽  
pp. 1-34
Author(s):  
Mirko Abbritti ◽  
Tommaso Trani
Keyword(s):  
Equilibrium Analysis ◽  
Intermediate Goods ◽  
Price Dynamics ◽  
Producer Price ◽  
Second Moments ◽  
Sensitivity Tests ◽  
The Us ◽  
B2b Relationships ◽  
Pass Through

We introduce business-to-business (B2B) relationships into an otherwise standard model to revisit two aspects of price dynamics in a unified analysis. On one side, the pass-through of cost shocks to prices is empirically incomplete. On the other side, the literature contains conjectures that long-term relationships may reduce the allocative role of price changes. After a partial equilibrium analysis of these aspects, we consider the general equilibrium effects. The formation of B2B relationships implies that the trade of intermediate goods depends on search, bargaining, and the adjustment along the intensive margin as opposed to the extensive margin. We find that, when this adjustment is costly, retailers have a relatively high bargaining power, and mismatch shocks are possible, the model can account for the second moments of the US producer price index and other variables. In this case, although its allocative role is low, the intermediate goods price affects the allocation of goods through the search externalities and is sufficiently volatile. The analysis includes several sensitivity tests and comparisons.

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.

ESR studies of coke formation on zeolite catalysts for methanol conversion

1987 ◽  
Vol 33 (2) ◽  
pp. 305-310 ◽  
Author(s):  
G. V. Echevskii ◽  
N. G. Kalinina ◽  
V. F. Anufrienko ◽  
V. A. Poluboyarov
Keyword(s):  
Coke Formation ◽  
Methanol Conversion ◽  
Zeolite Catalysts

Methanol conversion to light olefins over SAPO-34: kinetic modeling of coke formation

2000 ◽  
Vol 35-36 ◽  
pp. 121-135 ◽  
Author(s):  
D. Chen ◽  
H.P. Rebo ◽  
A. Grønvold ◽  
K. Moljord ◽  
A. Holmen
Keyword(s):  
Kinetic Modeling ◽  
Coke Formation ◽  
Methanol Conversion ◽  
Light Olefins

scholarly journals Enzymatic synthesis of l-fucose from l-fuculose using a fucose isomerase from Raoultella sp. and the biochemical and structural analyses of the enzyme

2019 ◽  
Vol 12 (1) ◽  
Author(s):  
In Jung Kim ◽  
Do Hyoung Kim ◽  
Ki Hyun Nam ◽  
Kyoung Heon Kim
Keyword(s):  
Biochemical Analysis ◽  
Equilibrium Composition ◽  
Structural Data ◽  
Binding Pocket ◽  
Equilibrium Mixture ◽  
Industrial Applications ◽  
Substrate Binding Pocket ◽  
Rare Sugar ◽  
Food Industries ◽  
Crystal Structural

Abstract Background l-Fucose is a rare sugar with potential uses in the pharmaceutical, cosmetic, and food industries. The enzymatic approach using l-fucose isomerase, which interconverts l-fucose and l-fuculose, can be an efficient way of producing l-fucose for industrial applications. Here, we performed biochemical and structural analyses of l-fucose isomerase identified from a novel species of Raoultella (RdFucI). Results RdFucI exhibited higher enzymatic activity for l-fuculose than for l-fucose, and the rate for the reverse reaction of converting l-fuculose to l-fucose was higher than that for the forward reaction of converting l-fucose to l-fuculose. In the equilibrium mixture, a much higher proportion of l-fucose (~ ninefold) was achieved at 30 °C and pH 7, indicating that the enzyme-catalyzed reaction favors the formation of l-fucose from l-fuculose. When biochemical analysis was conducted using l-fuculose as the substrate, the optimal conditions for RdFucI activity were determined to be 40 °C and pH 10. However, the equilibrium composition was not affected by reaction temperature in the range of 30 to 50 °C. Furthermore, RdFucI was found to be a metalloenzyme requiring Mn2+ as a cofactor. The comparative crystal structural analysis of RdFucI revealed the distinct conformation of α7–α8 loop of RdFucI. The loop is present at the entry of the substrate binding pocket and may affect the catalytic activity. Conclusions RdFucI-catalyzed isomerization favored the reaction from l-fuculose to l-fucose. The biochemical and structural data of RdFucI will be helpful for the better understanding of the molecular mechanism of l-FucIs and the industrial production of l-fucose.

The formation and degradation of active species during methanol conversion over protonated zeotype catalysts

2015 ◽  
Vol 44 (20) ◽  
pp. 7155-7176 ◽  
Author(s):  
U. Olsbye ◽  
S. Svelle ◽  
K. P. Lillerud ◽  
Z. H. Wei ◽  
Y. Y. Chen ◽  
...  
Keyword(s):  
Methanol Conversion ◽  
Active Species ◽  
Current Understanding ◽  
Methanol To Hydrocarbon

Studies leading to the current understanding of the initial and final stages of the methanol to hydrocarbon (MTH) reaction are reviewed.

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