Hydrogen to Carbon Monoxide Ratio

A mixture of the two reactants carbon monoxide and hydrogen is called synthesis gas and IS prepared by several processes The most widely used route to synthesis gas employs methane (from natural gas) and gives a 3 1 hydrogen to carbon monoxide ratio... 

Conversion to Hydrogen (Water Gas Shift Reaction). Carbon monoxide reacts with water over a catalyst to produce hydrogen and carbon monoxide (25). This reaction is used to prepare high purity hydrogen or synthesis gas with a higher hydrogen-to-carbon monoxide ratio than the feed (eq. 3). 

One of the most important, and perhaps the best studied, applications of three-phase fluidization is for the hydrogenation of carbon monoxide by the Fischer-Tropsch (F-T) process in the liquid phase. In this process, synthesis gas of relatively low hydrogen to carbon monoxide ratio (0.6 0.7) is bubbled through a slurry of precipitated catalyst suspended in a heavy oil medium. The F-T synthesis forms saturated and unsaturated hydrocarbon compounds ranging from methane to high-melting paraffin waxes (MW > 20,000) via the following two-step reaction ... 

The thermodynamics of the above reactions are illustrated in Figures 5.6 and 5.7174. Both figures assume a steam-to-methane ratio of 1.0. Figure 5.6 illustrates how the feed and product gases interact when the product gas has a hydrogen-to-carbon monoxide ratio of 3.0. Figure 5.7 illustrates the effects of temperature and pressure on the reactions. As pressure increases, lower conversion can be expected and more methane will not be converted and will be found in the reformer discharge stream. 

Oxygen-blown ATR with natural gas is used today in very large units that generate a mixture of CO and H2 for the Fischer-Tropsch process or methanol synthesis. This is attractive in part because the units can produce the hydrogen-to-carbon monoxide ratio needed in the synthesis step. Since the heat of reaction is added by combustion with oxygen, the catalyst can be incorporated as a fixed bed that can be scaled up to achieve further benefits of larger plant size in both the... 

In the Canadian context there need not be a restriction on biomass conversion processes to be self-sufficient and therefore be required to sacrifice carbon to drive the processes, Natural gas and hydro/nuclear electricity are likely to be available on a large scale through to the early decades of the next century. One or all of the following options have been discussed in the context of biomass conversion and in the specific case of methane additions to alter hydrogen to carbon monoxide ratios in syn gas work is presently under way to combine oxygen blown wood gasification with the reforming of natural gas, (5),... 

Synthesis gas production from combined CO2 reforming and partial oxidation of natural gas Maximization of both methane conversion and carbon monoxide selectivity while maintaining tiie hydrogen to carbon monoxide ratio close to 1. Real-coded NSGA with blend crossover Empirical models were used for optimization. Mohanty (2006)... 

In some cases, instead of changing each independent variable separately, a group can be formed. As an example we can refer to hydroformylation reactions, where such a group could be the hydrogen to carbon monoxide ratio. 

Petrochemical applications of syngas require a ratio of hydrogen to carbon monoxide of either 1 1 or 2 1. Commercial processes for syngas yield ratios much higher therefore, separation technology, by-product credits and production techniques which can adjust the hydrogen to carbon monoxide ratio are important aspects of syngas production. 

The desired products are synthesis gas mixtures of various hydrogen to carbon monoxide ratios, pure hydrogen, pure carbon monoxide and carbon dioxide. Although carbon dioxide is sometimes recovered as a byproduct and sold on the merchant market, it is not currently used as a feedstock for petrochemical production. The others, however, are important petrochemical feedstocks. 

The relative importance of these reactions to each other depends on many factors including the FT catalyst, the type of reactor and the composition of the synthesis gas, in particular its hydrogen to carbon monoxide ratio. 

A. Plant configuration. (1) The hydrogen-to-carbon monoxide ratio of the syngas is well suited to combined production of methanol and acetic anhydride. Although the hydrogen is not needed for production of acetic anhydride via carbonylation, it is used to decrease the hydrogen deficiency in the feed gas and thus minimizes use of the water-gas... 

There are several processes for purifying synthesis gas made from coal, coke, or oil. The impurities usually include H2S, CS2, COS, ungasified carbon, and residual ash. Other factors that influence the selection of a purification process are the hydrogen-to-carbon monoxide ratio and the carbon dioxide content. 

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