Water with partial methane

In a partial oxidation process, methane and other hydrocarbons in natural gas are combined with a limited amount of oxygen (typically, from air) that is not enough to completely oxidize the hydrocarbons to carbon dioxide and water. With less than the stoichiometric amount of oxygen available for the reaction, the reaction products contain primarily hydrogen and carbon monoxide (and nitrogen, if the reaction is carried out with air rather than pure oxygen) and a relatively small amount of carbon dioxide and other compounds. Subsequently, in the WGS reaction, the carbon monoxide reacts with water to form carbon dioxide and more hydrogen. 

Production of Hydrogen and Synthesis Gas by Combining Thermal Water Spaltimg with Partial Oxidation of Methane... 

The adsorption of methane does not lead to significant changes in the band intensity of free silanols because of the weak interaction of nonpolar CH4 molecules with the silica surface. However, calculations of the free surface area (5ir) on the basis of the integral intensity of free silanols at VoH = 3747 cm" (as a surface characteristic) and a band at 1870 cm" as a bulk Si-0 combination mode (used as an internal standard related to the nanoparticle volume), according to a method described by McCool et al. (2006), give 5ir=263.3 m /g for A-300 alone (with adsorbed water from air) and 266.9 and 265.9 m /g for silica with methane adsorbed for 1 and 7 min, respectively. An increase in the value is due to partial desorption of water resulting from methane flow the cell. It should be noted that the value can be considered as a portion of the surface area free from adsorbates, since it is determined from the band of free silanols at 3747 cm", and it is close... 

Jiang, H. Q., Wang, H. H., Werth, V., Schiestel, T., Caro, J. (2(X)8). Simultaneous production of hydrogen and synthesis gas by combining water spHtting with partial oxidation of methane in a hollow-fiber membrane reactor. Angewandte Chemie, Intematiorwl Edition, 47(48), 9341-9344. 

The term hydrophilic is often said to describe substances or groups that attract water, with the term hydrophobic used for substances or groups that repel water and attract hydrocarbons. In fact, the molecules of a hydrophobic substance exert an electronic van der Waals attraction on water molecules as well as on hydrocarbon molecules. For example, the solubility at 25°C of water vapor at 0.0313 atm pressure (the vapor pressure of liquid water at this temperature) in kerosene (a mixture of hydrocarbons) is 72 mg per kg of solvent, whereas the solubility of methane at the same partial pressure is somewhat less, 10 mg per kg of kerosene. The water molecules are attracted somewhat more strongly by the kerosene molecules than are the methane molecules. The difference between water and methane is that at a higher partial pressure water vapor condenses to liquid water, which is stabilized by the intramolecular hydrogen bonds, whereas methane remains a gas. 

Synthesis gas (syn. gas) is a mixture of hydrogen and carbon monoxide. It may also include some carbon dioxide. Natural gas (methane) can be converted into syn. gas by reaction with water (steam reforming) and/or by partial oxidation. There are also several commercially proven processes for the gasification of coal using steam and oxygen (air. ), which yield mixtures of H, CO and CO, sometimes with some methane. Of these the Lurgi process uses a fixed bed reactor... 

Jiang, H., Wang, H., Werth, S., et al. (2008). Simultaneous Production of Hydrogen and Synthesis Gas by Combining Water Splitting with Partial Oxidation of Methane in a Hollow-Fiber Membrane Reactor, Angew. Chem. Int. Edit., 47, pp. 9341-9344. 

The carbon black (soot) produced in the partial combustion and electrical discharge processes is of rather small particle si2e and contains substantial amounts of higher (mostly aromatic) hydrocarbons which may render it hydrophobic, sticky, and difficult to remove by filtration. Electrostatic units, combined with water scmbbers, moving coke beds, and bag filters, are used for the removal of soot. The recovery is illustrated by the BASF separation and purification system (23). The bulk of the carbon in the reactor effluent is removed by a water scmbber (quencher). Residual carbon clean-up is by electrostatic filtering in the case of methane feedstock, and by coke particles if the feed is naphtha. Carbon in the quench water is concentrated by flotation, then burned. 

Ethane, like methane, is a colorless gas that is insoluble in water. It does not react with acids and bases, and is not very reactive toward many reagents. It can also be partially oxidized to a carbon monoxide and hydrogen mixture or chlorinated under conditions similar to those used... 

In practice, this ratio is even lower than what is shown hy the stoichiometric equation because part of the methane is oxidized to carhon dioxide and water. When resids are partially oxidized hy oxygen and steam at 1400-1450°C and 55-60 atmospheres, the gas consists of equal parts of hydrogen and carhon monoxide. Table 4-2 compares products from steam reforming natural gas with products from partial oxidation of heavy fuel oil. 

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