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The disadvantage with a copper catalysts is that it is very sensitive when it comes to sulfide poisoning, a future use of for example a cobalt- molybdenum catalyst could solve this problem. The catalyst mainly used in the industry today is a copper-zinc-alumina (Cu/ZnO/Al 2 O 3) based catalyst.
The surface area of a solid catalyst has a strong influence on the number of available active sites. In industrial practice, solid catalysts are often porous to maximize surface area, commonly achieving 50–400 m 2 /g. [2] Some mesoporous silicates, such as the MCM-41, have surface areas greater than 1000 m 2 /g. [10]
An illustrative example is the effect of catalysts to speed the decomposition of hydrogen peroxide into water and oxygen: . 2 H 2 O 2 → 2 H 2 O + O 2. This reaction proceeds because the reaction products are more stable than the starting compound, but this decomposition is so slow that hydrogen peroxide solutions are commercially available.
Natural gas has a high hydrogen to carbon ratio, so the water-gas shift is not needed for cobalt catalysts. Cobalt-based catalysts are more sensitive than their iron counterparts. Illustrative of real world catalyst selection, high-temperature Fischer–Tropsch (HTFT), which operates at 330–350 °C, uses an iron-based catalyst.
These ill-defined but highly active homogeneous catalysts remain in industrial use. [6] The first well-defined ruthenium catalyst was reported in 1992. [7] It was prepared from RuCl 2 (PPh 3) 4 and diphenylcyclopropene. First Grubbs-type catalyst. This initial ruthenium catalyst was followed in 1995 by what is now known as the first-generation ...
Ziegler–Natta catalysts of the third class, non-metallocene catalysts, use a variety of complexes of various metals, ranging from scandium to lanthanoid and actinoid metals, and a large variety of ligands containing oxygen (O 2), nitrogen (N 2), phosphorus (P), and sulfur (S). The complexes are activated using MAO, as is done for metallocene ...
Enzymes are homogeneous catalysts that are essential for life but are also harnessed for industrial processes. A well-studied example is carbonic anhydrase, which catalyzes the release of CO 2 into the lungs from the bloodstream. Enzymes possess properties of both homogeneous and heterogeneous catalysts. As such, they are usually regarded as a ...
The Monsanto process is an industrial method for the manufacture of acetic acid by catalytic carbonylation of methanol. [1] The Monsanto process has largely been supplanted by the Cativa process, a similar iridium-based process developed by BP Chemicals Ltd, which is more economical and environmentally friendly.