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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.
In the Gutzeit test, AsH 3 is generated by reduction of aqueous arsenic compounds, typically arsenites, with Zn in the presence of H 2 SO 4. The evolved gaseous AsH 3 is then exposed to AgNO 3 either as powder or as a solution. With solid AgNO 3, AsH 3 reacts to produce yellow Ag 4 AsNO 3, whereas AsH 3 reacts with a solution of AgNO 3 to give ...
A typical hydrogen demand is ~80 kg [citation needed] hydrogen per ton of dry, ash-free coal. Generally, this process is similar to hydrogenation. The output is at three levels: heavy oil, middle oil, gasoline. The middle oil is hydrogenated in order to get more gasoline and the heavy oil is mixed with the coal again and the process restarts.
Steam can be added to the reaction in order to increase the generation of H 2, via the water-gas shift reaction (WGS) and/or steam methane reforming. The CLR process can produce a syngas with a H 2:CO molar ratio of 2:1 or higher, which is suitable for Fischer–Tropsch synthesis, methanol synthesis, or hydrogen production. The reduced oxygen ...
One of the simplest arsenic compounds is the trihydride, the highly toxic, flammable, pyrophoric arsine (AsH 3). This compound is generally regarded as stable, since at room temperature it decomposes only slowly. At temperatures of 250–300 °C decomposition to arsenic and hydrogen is rapid. [34]
It was discovered that adding steam to the input air of a gas producer would increase the calorific value of the fuel gas by enriching it with CO and hydrogen (H 2) produced by water gas reactions. Producer gas has a very low calorific value of 3.7 to 5.6 MJ/m 3 (99 to 150 Btu/cu ft); because the calorific gases CO/H 2 are diluted with much ...
Synthesis gas ("syngas") is obtained from biomass/coal gasification is a mixture of hydrogen and carbon monoxide. The H 2:CO ratio is adjusted using the water-gas shift reaction. Coal-based FT plants produce varying amounts of CO 2, depending upon the energy source of the gasification process. However, most coal-based plants rely on the feed ...
The solid coal is gasified to produce syngas, or synthetic gas. Syngas is synthesized by gasifying coal in a closed pressurized reactor with a shortage of oxygen. The shortage of oxygen ensures that coal is broken down by the heat and pressure as opposed to burning completely. The chemical reaction between coal and oxygen produces a product ...