Carbon monoxide syngas conversion

Figure 1.2 Carbon monoxide (CO) conversion in the water gas shift (WGS) reaction as a function of temperature and steam/syngas (S/G) ratio with a biosyngas feed (inlet composition CO, 22% CO2, 15% Hj, 20% other compounds inert for WGS, 43%).

The partial oxidation of methane in catalytic monoliths at short contact-times is another example with several empty routes illustrating importance of thermodynamic consistency in selection of kinetic parameters. This reaction offers a promising route for the conversion of natural gas into more useful chemicals such as synthesis gas (syngas), a mixture of hydrogen and carbon monoxide. Syngas can subsequently be converted into methanol or higher hydrocarbons. The kinetic model for partial oxidation of methane on Rh includes 19 reversible reactions with six-gas phase species and 11 adsorbed species [5]. Presence of 19 steps, one balance equation (which relates coverage of surface species) and... 

Steam Utilization. Less steam is used in the RMProcess than is required for conventional shift conversion even though in other methanation processes as little as one-half of the total syngas is processed through shift conversion in order to achieve a near-stoichiometric balance of hydrogen and carbon monoxide for methanation. 

Conversly, the Fe3(C0)12 NaY adduct is active for syngas conversion. A non-decomposed sample exhibits a significant activity at 230°C whereas the catalytic efficiency for the decar-bonylated one already appears at 200°C. Infrared experiments show an increase in the stability of the Fe3(C0)- 2 units upon thermal treatment under CO atmosphere so that total carbon monoxide evolution only takes place at 230°C thus suggesting that the catalyst is certainly not Fe3(C0)- 2. This cluster has to be transformed into higher nuclearity species which bind less strongly with carbon monoxide upon CO re-adsorption (1 7). 

Ci chemistry can no longer be equated only with syngas chemistry. Nature s own C02 photosynthesis and bacterial methane conversion are also Ci conversion processes. We are far from approaching these processes for practical synthetic use efficiently. Production of methane from carbon dioxide (similarly to carbon monoxide) and hydrogen is a feasible process (methanation).80 Similarly, reduction of carbon dioxide with hydrogen to methyl alcohol81 can be readily carried out, and the method has been industrially developed ... 

Using the catalyst system known from the Monsanto process, Dumas et at. have been able to direct the reaction towards ethanol formation using syngas mixtures extremely rich in hydrogen [87]. As is shown in Table XII, no acetic acid and only minor amounts of acetates are formed at an H3/CO ratio of 60. Ethanol and acetaldehyde aie the main products along with considerable amounts of methyl ethyl ether. Unfortunately, the Dumas c/ at. based the yields and conversion on carbon monoxide and not on methanol. This makes the data of this interesting process difficult to compare with those of other catalyst systems. 

All commercially produced methanol is made by the catalytic conversion of syngas containing carbon monoxide, carbon dioxide, and hydrogen as the main components. The basic reactions involved in methanol synthesis are... 

There are various feedstocks and chemical conversion reaction schemes that can be used to produce synthetic ultra-clean fuels. All start with the production of syngas, a hy ogen/carbon monoxide mixture. 

When the object of reforming natural gas is to produce hydrogen and not to prepare organic chemicals or carbonaceous fuels, it is necessary to complete the conversion by subjecting the syngas to the WGS reaction. This converts the carbon monoxide to carbon dioxide by further reaction with steam over a catalyst at a much lower temperature, i.e.. 

Iron-based Fischer-Tropsch (FT) catalysts undergo a series of phase transformations during activation and use (1). Activation with carbon monoxide or syngas typically results in the conversion of Fe O to Fe O and ultimately to one or more iron carbides (2). During FT synthesis, iron carbides can be oxidized to Fe O if the or COj/CO ratios are high... 

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