Steam reforming of natural gas and

Today the two most common methods used to produce hydrogen are (1) steam reforming of natural gas, and (2) electrolysis of water. The predominant method for producing synthesis gas is steam reforming of natural gas, although other hydrocarbons can be used as feedstocks. For example, hydrogen can be produced from the biomass reforming process. 

One of the more important alternatives to the blast furnace for the production of iron is direct reduction of pelletised ore in a shaft reactor. The reducing gas mixture is usually obtained by steam reforming of natural gas and flows upward,countercurrent to the downward flow of solids. Sponge iron obtained by direct reduction may be used directly in arc furnaces for steel production. 

Thus we have several different processes for the production of hydrogen and CO for methanol synthesis. The most important today continues to be steam reforming of natural gas and naphtha. 

Although the above-discussed studies have defined sulfur-poisoning tolerances for conventional nickel catalysts used in steam reforming of natural gas and naptha, they have not considered in sufficient detail the kinetics of poisoning at above-threshold concentrations nor the effects of catalyst and/or gas compositions on rate of deactivation and tolerance level. Nor is there any previous report on the effects of sulfur on product distribution (i.e., relative rates of production of H 2, CO, CH4) in steam reforming of hydrocarbons. 

The raw synthesis gas produced by steam reforming of natural gas and light hydrocarbon feedstocks is free of sulfur. Any sulfur contained in the feedstock has to be removed of upstream of gasification to avoid poisoning of the sensitive reforming catalysts. This is usually performed by hydrodesulfurization and adsorption of the H2S by ZnO. As this is an essential part of the steam reforming process, it was already treated in Section 4.1.1. 

Steam Reforming of Natural Gas and Subsequent Synthesis of Methanol ... 

Cll-NK, a commercial nickel-based catalyst used for steam reforming of natural gas and naphtha, was obtained from United Catalysts and ground to the particle size of 300-500p. 

In practice, to recover the CO contained in a feedstock produced, for instance, by steam reforming of natural gas, and which is hence virtually free of nitrogen and available at 2. 10 Pa absolute, the installation has the following basic (low sheet... 

Figure 32.1 Hydrogen, carbon monoxide, and methane concentrations in chemical equilibrium based on the steam reforming of natural gas and the WGS reaction for a steam-to-methane ratio of 2.5.

Steam reforming of natural gas and other hydrocarbons remains the cheapest route to large-scale commercial production of hydrogen [251] [414] [426]. The costs are increased if CCS is included as illustrated in Table 2.1. 

The majority of the hydrogen produced in the United States is consumed at or within pipeline distances of the production site. Hydrogen is produced directly by steam reforming of natural gas, and electrolysis of water. It may also be produced directly by steam reforming of heavy hydrocarbons, and ammonia dissociation. 

Based on methane, the overall stoichiometric equation of NH3 synthesis via steam reforming of natural gas (and the subsequent secondary reforming and water gas shift) is given by... 

There are several commercial gas-solid catalysed reactions in which heat transfer plays a significant, if not dominant, role in limiting the reactor productivity, lowering the process selectivity and reducing the life of the catalyst. Among these include the oxidation of ethylene, benzene, C hydrocarbons and methanol, the ammoxidation of propylene, methanol synthesis (Lurgi), the hydrochlorination of methanol and steam reforming of natural gas and naphtha. 

The Ni-cermet with either stabilised zirconia, most often yttria stabilised zirconia (YSZ), or doped ceria has so far been the most successful anode in SOFCs in spite of the many problems associated with this electrode. The main reason for this is the excellent catalytic and electrocatalytic property of Ni for steam reforming of natural gas and for electrochemical oxidation of H2 and CO. These properties have been so good that they have overshadowed several drawbacks such as the sensitivity to sulphur poisoning and mechanical instability in case of redoxing. Furthermore, the electrode is fully reversible, i.e. works equally well in fuel cell and in electrolysis mode. 

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