Stage water-gas shift

Then, the significant improvement in the CO conversion was obtained by introducing multi-stage water-gas shift reactor in the ammonia synthesis plant. The first stage is characterized by working at higher temperatures, favouring... 

K.-R. Hwang, S.-Ki Ihm, S.-C. Park, J.-S. Park, Pt/Zr02 catalyst for a single-stage water-gas shift reaction Ti addition effect, Int. J. Hydrogen Energy 38 (2013) 6044—6051. 

V. M. Shinde, G. Madras, A single-stage water-gas shift reaction over highly active and stable Si- and Al-substituted Pt/Ce02 catalysts, Chem. Cat. Chem. 4 (2012) 1968-1978. 

K. G. Azzam, I. V. Babich, K. Seshan, L. Lefferts, Single stage water gas shift conversion over Pt/ri02 - problem of catalyst deactivation, Appl. Catal. A Gen. 338 (2008) 66-71. 

Design and test of a two-stage water-gas-shift reactor at a 5 kWe-scale. Presented at the 3rd European PECF Forum, Lucerne, Switzerland. 

Cutillo et al. also analysed the effect of introducing a carbon monoxide tolerant fuel cell into the system, which would make the overall system less complex [443]. Because such fuel cells were expected to be less efficient, about 3% lower efficiency was assumed. Another potential simplification was the removal of one of the water-gas shift reactors. The two stage water-gas shift reactors could be replaced by a medium temperature water-gas shift reactor with higher carbon monoxide outlet concentration in combination with the high carbon monoxide tolerant fuel cell. Alternatively, a water-gas shift reactor with heat-exchange capabilities, as discussed in Section 5.2.1, could be placed into such a system and combined with preferential oxidation and low temperature PEM fuel cell technology. 

The catalytic carbon monoxide clean-up worked with a two-stage water-gas shift in tubular reactors cooled by steam generation. The kinetics for a rhenium-alumina catalyst for high temperature water-gas shift and for a copper/alumina catalyst for low temperature shift had been extracted from the literature. 

Figure 9.46 Fuel processor reactor temperatures and carbon monoxide concentration after the second stage water-gas shift (WCS2 CO) and after the second stage preferential oxidation reactor (PrOx CO) as determined during start-up of a gasoline fuel processor to full power [519].

The partial-oxidation process differs only in the initial stages before the water gas shift converter. Because it is a noncatalyzed process, desulfurization can be carried out further downstream. The proportions of a mixture of heavy oil or coal, etc, O2, and steam, at very high temperature, are so adjusted that the exit gases contain a substantial proportion of H2 and carbon monoxide. 

Shift Conversion. Carbon oxides deactivate the ammonia synthesis catalyst and must be removed prior to the synthesis loop. The exothermic water-gas shift reaction (eq. 23) provides a convenient mechanism to maximize hydrogen production while converting CO to the more easily removable CO2. A two-stage adiabatic reactor sequence is normally employed to maximize this conversion. The bulk of the CO is shifted to CO2 in a high... 

Once particulate matter is removed, the syngas passes through a two stages catalytic reactor, where CO reacts with steam to produce C02 and further yield H2 water-gas-shift (WGS) reaction. 

It is partly the fault of statistics that experimenters have misconstrued the value of the number and precision of data points relative to the value of the location of the points. The importance of the location of the data in the model specification stage can be seen from Fig. 1, which represents literature data (M3) on sulfur dioxide oxidation. The dashed and solid lines represent the predicted rates of two rival models, and the points are the results of two series of experimental runs. It can be seen that neither a greater number of experimental points nor data of greater precision will be of major assistance in discriminating between the two rival models, if data are restricted to the total pressure range from 2 to 10 atm. These data simply do not place the models in jeopardy, as would data below 2 atm and greater than 10 atm total pressure. This is presumably the problem in the water-gas shift reaction, which is classical in terms of the number of models proposed, each of which adequately represent given sets of data. 

H20 + CO - COj + H2 (water-gas shift) Fe304 promoted with Cr203 (adiabatic fixed bed) for a second, lower temperature stage, Cu-ZnO on A1203 C0M0 on support... 

Conventionally the reaction is performed in two stages, the so-called high- and low-temperature water-gas shift. In large-scale industrial processes, Fe203/Cr203 catalysts are applied for high-temperature shift (which is then performed between... 

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