Steam carbon monoxide reaction with

After the reforming reaction, the gas is quickly cooled down to about 350 450 °C before it enters the (high-temperature) water-gas shift reaction (CO shift). Here, the exothermic catalytic conversion takes place of the carbon monoxide formed with steam to hydrogen (H2) and carbon dioxide (C02) in the following reaction ... 

The water-gas shift (WGS) reaction is an important reaction in many commercial processes where hydrogen has to be generated or where CO must be converted. In the WGS reaction carbon monoxide together with steam is converted to carbon dioxide and hydrogen. The reaction is a reversible chemical reaction, usually assisted by a catalyst (see Eq. (14.8)). 

Kulkova, N.V. Temkin, M.I. Kinetics of the reaction of carbon monoxide conversion with steam. Zh. Fiz. Chim. (USSR) 1949,23 (6), 695-713. 

Chemical Use. Both natural gas and natural gas Hquids are used as feedstocks in the chemical industry. The largest chemical use of methane is through its reactions with steam to produce mixtures of carbon monoxide and hydrogen (qv). This overall endothermic reaction is represented as... 

Steam, at high temperatures (975-1375 K) is mixed with methane gas in a reactor with a Ni-based catalyst at pressures of 3-25 bar to yield carbon monoxide (CO) and hydrogen (H ). Steam reforming is the process by which methane and other hydrocarbons in natural gas are converted into hydrogen and carbon monoxide by reaction with steam over a nickel catalyst on a ceramic support. The hydrogen and carbon monoxide are used as initial material for other industrial processes. 

The SMR process consists of two steps. The first is the reformation process in which methane mixed with steam is passed over a catalyst bed at high temperature and pressure to form a mixture of hydrogen and carbon monoxide (reaction 1.1), called syngas. The second step is the shift reaction in which carbon monoxide from the first stage reacts with additional steam to release carbon dioxide and more hydrogen (reaction 1.2). 

All these cells are anodically combusting hydrogen, although MCFCs and SOFCs may be supplied with methane or carbon monoxide from which by internal reforming and/or shift reaction with steam within the cell the hydrogen may be generated in situ (98-100). 

After this preliminary study, we measured the rates of methane reaction with steam (i.e., r values in the r+ > r region), and the rates of carbon monoxide hydrogenation [i.e., ( —r) values in the r+ < region] at 470, 530, 600, and 700°C (84). In these experiments the PCH4 and Pco values did not exceed 0.2 and 0.1 atm, respectively therefore, (27 7) and (278) were applicable. Variations in catalytic activity were taken into account on the basis of control experiments. 

Where hydrogen is desired, it is necessary to oxidize the carbon monoxide by further reaction with steam through the water-gas catalytic reaction since by this means an extra mol of hydrogen is obtained per mol of carbon monoxide present in the gas. 

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.. 

The indirect liquefaction of coal involves a two-stage conversion operation in which coal is first converted (by reaction with steam and oxygen) (Chapters 20 and 21) to produce a gaseous mixture that is composed primarily of carbon monoxide and hydrogen (syngas synthesis gas). 

The other category of coal liqnefaction processes invokes the concept of the indirect liquefaction of coal. In these processes, the coal is not converted directly into liquid products but involves a two-stage conversion operation in which coal is first converted (by reaction with steam and oxygen) to prodnce a gaseons mixture that is composed primarily of carbon monoxide and hydrogen (syngas synthesis gas). The gas stream is snbseqnently pnrified (to remove snlfur, nitrogen, and any particnlate matter) after which it is catalytically converted to a mixtnre of liquid hydrocarbon prodncts. 

Carbon monoxide is manufactured industrially from natural gas (CH4) and petroleum hydrocarbons, either by reaction with steam or by partial oxidation. For example,... 

The carbon monoxide prodnced with hydrogen in steam reforming is a potential problem. This is becanse it will poison any platinum catalyst, as used in PEMFCs or PAFCs. With these fnel cells, the reformate gas must be further processed by means of the water-gas shift reaction (nsnally abbreviated to the shift reaction) ... 

---