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The first step in the WGS reaction is the high temperature shift which is carried out at temperatures between 320 °C and 450 °C. As mentioned before, the catalyst is a composition of iron-oxide, Fe 2 O 3 (90-95%), and chromium oxides Cr 2 O 3 (5-10%) which have an ideal activity and selectivity at these temperatures.
All of the cracking reactions take place in the catalyst riser within a period of 2–4 seconds. The hydrocarbon vapours "fluidize" the powdered catalyst and the mixture of hydrocarbon vapors and catalyst flows upward to enter the reactor at a temperature of about 535 °C and a pressure of about 1.72 bar.
The catalytic cycle of the Monsanto process. The catalytically active species is the anion cis-[Rh(CO) 2 I 2] − (top of scheme). [3] The first organometallic step is the oxidative addition of methyl iodide to cis-[Rh(CO) 2 I 2] − to form the hexacoordinate species [(CH 3)Rh(CO) 2 I 3] −.
In marine applications, this can increase fresh water requirements as the boiler must be continuously washed to remove the deposits. Most catalysts on the market have porous structures and a geometries optimized for increasing their specific surface area (a clay planting pot is a good example of what SCR catalyst feels like). This porosity is ...
High surface area facilitates catalytic reaction or filtration. The open spaces in the cross-sectional area are 72 to 87% of the frontal area, so resistance to the flow of gases through the holes is low, which minimizes energy consumed forcing gases through the structure. The monolith is a substrate that supports a catalyst.
[3] The shapes which the catalysts are packed onto must be able to form a consistent geometric arrangement to provide equal spacing in the catalyst bed (an area in the distillation column where the reactant and catalyst come into contact to form the products). This spacing is meant to ensure the catalysts are spread evenly within the column.
A slurry reactor contains the catalyst in a powdered or granular form. [7] This reactor is typically used when one reactant is a gas and the other a liquid while the catalyst is a solid. The reactant gas is put through the liquid and dissolved. It then diffuses onto the catalyst surface.
For this reason, a ratio of nitrogen to hydrogen of 1 to 3, a pressure of 250 to 350 bar, a temperature of 450 to 550 °C and α iron are optimal. The catalyst ferrite (α-Fe) is produced in the reactor by the reduction of magnetite with hydrogen. The catalyst has its highest efficiency at temperatures of about 400 to 500 °C.