Search results
Results from the WOW.Com Content Network
Paul Sabatier (1854-1941) winner of the Nobel Prize in Chemistry in 1912 and discoverer of the reaction in 1897. The Sabatier reaction or Sabatier process produces methane and water from a reaction of hydrogen with carbon dioxide at elevated temperatures (optimally 300–400 °C) and pressures (perhaps 3 MPa [1]) in the presence of a nickel catalyst.
The methanation reactions are classified as exothermic and their energy of formations are listed. [ 1 ] There is disagreement on whether the CO 2 methanation occurs by first associatively adsorbing an adatom hydrogen and forming oxygen intermediates before hydrogenation or dissociating and forming a carbonyl before being hydrogenated. [ 3 ]
The water–gas shift reaction (WGSR) describes the reaction of carbon monoxide and water vapor to form carbon dioxide and hydrogen: CO + H 2 O ⇌ CO 2 + H 2. The water gas shift reaction was discovered by Italian physicist Felice Fontana in 1780. It was not until much later that the industrial value of this reaction was realized.
The Bosch reaction is a catalytic chemical reaction between carbon dioxide (CO 2) and hydrogen (H 2) that produces elemental carbon (C,graphite), water, and a 10% return of invested heat. CO 2 is usually reduced by H 2 to carbon in presence of a catalyst (e.g. iron (Fe)) and requires a temperature level of 530–730 °C (986–1,346 °F).
The water gas shift reaction is the reaction between carbon monoxide and steam to form hydrogen and carbon dioxide: CO + H 2 O ⇌ CO 2 + H 2. This reaction was discovered by Felice Fontana and nowadays is adopted in a wide range of industrial applications, such as in the production process of ammonia, hydrocarbons, methanol, hydrogen and other chemicals.
The Fischer–Tropsch process involves a series of chemical reactions that produce a variety of hydrocarbons, ideally having the formula (C n H 2n+2). The more useful reactions produce alkanes as follows: [7] (2n + 1) H 2 + n CO → C n H 2n+2 + n H 2 O. where n is typically 10–20. The formation of methane (n = 1) is unwanted.
If, however, hydrogen is the desired end-product, the coal gas (primarily the CO product) undergoes the water gas shift reaction where more hydrogen is produced by additional reaction with water vapor: CO + H 2 O → CO 2 + H 2. Although other technologies for coal gasification currently exist, all employ, in general, the same chemical processes.
The reaction is endothermic, so the fuel must be continually re-heated to maintain the reaction. To do this, an air stream, which alternates with the vapor stream, is introduced to combust some of the carbon: O 2 + C → CO 2 (ΔH = -393 kJ/mol) Theoretically, to make 6 L of water gas, 5 L of air is required.