Methanol synthesis catalyst production

Ammonia, Hydrogen, and Methanol Production The ammonia synthesis catalyst is metallic iron promoted with AljO,. K 0. MgO. and CaO. The hydrogen-producing (methane reforming) catalyst is supported nickel. The methanol synthesis catalyst is ZnO promoted with Cr Oj or Cu(l>—ZnO promoted with CrjOl or AUOi. The respective reactions are cited as follows. 

We compared our novel catalysts with a commercial methanol synthesis catalyst Cu-Zn-A1 (Cu-Zn-Al=42 45 13, in atomic ratio). As shown in Fig.la, although the conversion of CO2 for the Cu-Zn-Al/HY composite catalyst was the highest (30.5%), the selectivity of hydrocarbons was the lowest (6.3%) in our study. The decomposition of methanol to CO at high temperatures accounts for the remarkable decrease in the selectivity of hydrocarbons. Moreover, because olefins are easily hydrogenated into paraffins over Cu-based catalysts [7], no olefins and only a trace of iso-butane appeared in the products. The Fe-Zn-Zr (1 1 1)... 

Catalytic hydrogenation of carbon dioxide was studied for the simultaneous synthesis of methanol and dimethyl ether (oxygenates). Various combinations of methanol synthesis catalysts and methanol dehydration catalysts have been examined for the hydrogenation. The hybrid catalyst of Cu/ZnO/CraOs and CuNaY zeolite was found to be very efficient for the production of oxygenates. 

The deactivation of methanol-synthesis catalyst was studied in laboratory and pilot-plant slurry reactors using a concentrated, poison-free, CO-rich feedstream. The extent of catalyst deactivation correlated with the loss of BET surface area. A model of catalyst deactivation as a function of temperature and time was developed from experimental data. The model suggested that continuous catalyst addition and withdrawal, rather than temperature programming, was the best way to maintain a constant rate of methanol production as the catalyst ages. Catalyst addition and withdrawal was demonstrated in the pilot plant. 

Experimental studies have demonstrated that conventional methanol-synthesis catalysts deactivate slowly in a slurry reactor, even with a concentrated, CO rich feedstream. The catalyst activity correlates with the BET surface area and the rate of deactivation increases rapidly with temperature. This limits the utility of temperature programming as a means for maintaining a constant methanol production rate as the catalyst ages. Continuous catalyst addition and withdrawal is the preferred means to maintain constant methanol production. The key mechanical and process features of this technique were demonstrated In the pilot plant. 

Only a few studies of the poisoning of copper/zinc oxide catalysts have been reported (refs. 4-6). Whether copper or zinc is most su.sceptible to attack by sulfur is still a question, Tlte literature findings on the sulfur tolerance of methanol synthesis catalyst are inconsistent with industrial experience. For example, observations from indusirinl production suggest that a... 

Then the product gas is fed to a low-temperature reactor where a Cu/Zn-Al2O3 particulate WGS catalyst works at about 200°C. Outlet CO concentration is decreased to <0.5%, while the remaining CO, which can poison downstream ammonia or methanol synthesis catalysts, is removed by pressure swing adsorption (PSA) unit. This method exploits the adsorption capacity of different molecular sieves or active carbon, which selectively permit the crossover of hydrogen but not of the other compounds present in the effluents. This technology has been... 

The catalytic CO hydrogenation activity for methanol production over Cu based catalysts are listed in Table 2. In Table 2, the activity of conventional copper based methanol synthesis catalysts, Cu/Zn0/Cr203 (Cu Zn Cr = 6 3 1) and Cu/Zn0/Al203 (Cu Zn AI = 4 5 1), as well as Cu-Yb203 prepared in the present work at various reaction... 

When carbon monoxide and hydrogen were treated at 400-450°C. in a copper-lined reaction tube in the presence of a methanol synthesis catalyst, small amounts of hydrocarbons were formed in addition to oxygenated products. Curve II (Fig. 6) shows the distillation curve for the C3-C4 fraction obtained with a zinc-copper catalyst. The C, fraction contained very small amounts of isobutane (0.2 g. per cubic meter of synthesis gas). 

Today methanol has become a very important feedstock for the production of many chemicals. Use as a clean fuel has increased and methanol is used in the production of the popular oxygenated fuel additive, MTBE. It has also been postulated that methanol could be a carrier of energy for safe transportation between remote countries. Furthermore, to prevent a greenhouse effect caused by COj generated from the tremendous oxidation reactions on the earth, methanol synthesis from CO2 is regarded as one of the potential solutions to decrease CO2 by the reaction with hydrogen which is produced by electrolysis of water, for example. Due to the increasing demand for methanol, many researchers are involved in the development of more active methanol synthesis catalysts. 

It is known that ZnO alone is a methanol synthesis catalyst [8,9,10], however, the impurities (for example, alkaline residues) introduced to the catalyst during the preparation accelerate side reactions including higher alcohol synthesis and hydrocarbon synthesis [9], In this paper, the support and the gold catalysts were prepared in a similar way, which enables us to investigate the function of gold over the supported catalysts. The results above show that the catalytic behaviour is improved with the addition of Au to the catalyst, since the Au/ZnO selectivity produces alcohols as products and there is a distinct increase in the selectivity for higher alcohols for Au/ZnO when compared with ZnO alone. 

The rapid rise in the production of methanol as chemical raw material first began in 1923 when the first large-scale synthesis plant was constructed by the Badische Anilin und Sodafabrik, Ludwigshafen (BASF). Based on the woik by Mittasch, M. Pier and his staff proved during test covering several years that iron is scarcely suitable as a catalyst for methanol production. On the contrary, it was established that iron must be carefully avoided in the production of methanol synthesis catalysts as its presence under the operating conditions applied to methanol synthesis leads to the formation of iron penta carbonyl which on its part resulted... 

Stull, Westrum, and Sinke devote a chapter to the discussion of the applications of thermodynamics to industrial problems. Subjects covered include the petroleum industry, chemicals from methane, styrene manufacture, acrylonitrile and vinyl chloride syntheses, methanol synthesis, formaldehyde production from methanol, acetic acid manufacture, the Gatterman-Koch reaction, and catalyst selection. 

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