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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 pressure on a pressure-temperature diagram (such as the water phase diagram shown above) is the partial pressure of the substance in question. A phase diagram in physical chemistry , engineering , mineralogy , and materials science is a type of chart used to show conditions (pressure, temperature, etc.) at which thermodynamically distinct ...
Most of the time, hydrogen is made by splitting methane (CH 4) into carbon dioxide (CO 2) and hydrogen (H 2) via steam reforming. This is a carbon-intensive process that means for every kilogram of “grey” hydrogen produced, approximately 10 kilograms of CO 2 are emitted into the atmosphere. [2]
Phase transitions commonly refer to when a substance transforms between one of the four states of matter to another. At the phase transition point for a substance, for instance the boiling point, the two phases involved - liquid and vapor, have identical free energies and therefore are equally likely to exist.
The Mollier enthalpy–entropy diagram for water and steam. The "dryness fraction", x , gives the fraction by mass of gaseous water in the wet region, the remainder being droplets of liquid. An enthalpy–entropy chart , also known as the H – S chart or Mollier diagram , plots the total heat against entropy, [ 1 ] describing the enthalpy of a ...
Efficient and economical water splitting would be a technological breakthrough that could underpin a hydrogen economy. A version of water splitting occurs in photosynthesis, but hydrogen is not produced. The reverse of water splitting is the basis of the hydrogen fuel cell. Water splitting using solar radiation has not been commercialized.
In the conversion of carbon dioxide to useful materials, the water–gas shift reaction is used to produce carbon monoxide from hydrogen and carbon dioxide. This is sometimes called the reverse water–gas shift reaction. [20] Water gas is defined as a fuel gas consisting mainly of carbon monoxide (CO) and hydrogen (H 2).
Organosulfur compounds are separated by pressure swing adsorption together with carbon dioxide after CO conversion. To produce hydrogen by steam reforming, methane reacts with water vapor using a nickel oxide-alumina catalyst in the primary reformer to form carbon monoxide and hydrogen.