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The figure on the right shows a volcano plot for the decomposition of formic acid using different transition metals as catalysts. [5] In this case, the heat of formation (Δ f H) of the metal formate salt was used for the x axis because studies showed that the reaction intermediate was a surface formate. For the y axis, the temperature at which ...
The two most common catalyst geometries used today are honeycomb catalysts and plate catalysts. The honeycomb form usually consists of an extruded ceramic applied homogeneously throughout the carrier or coated on the substrate. Like the various types of catalysts, their configuration also has advantages and disadvantages.
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.
A typical fluid catalytic cracking unit in a petroleum refinery. Fluid catalytic cracking (FCC) is the conversion process used in petroleum refineries to convert the high-boiling point, high-molecular weight hydrocarbon fractions of petroleum (crude oils) into gasoline, alkene gases, and other petroleum products.
Typical catalysts are platinum, and redox-active oxides of iron, vanadium, and molybdenum. In many cases, catalysts are modified with a host of additives or promoters that enhance rates or selectivities. Important homogeneous catalysts for the oxidation of organic compounds are carboxylates of cobalt, iron, and manganese
Typical route for alkylation of benzene with ethylene and ZSM-5 as a heterogeneous catalyst. Alkylation is a chemical reaction that entails transfer of an alkyl group. The alkyl group may be transferred as an alkyl carbocation, a free radical, a carbanion, or a carbene (or their equivalents). [1] Alkylating agents are reagents for effecting ...
The catalysts used for catalytic distillation are composed of different substances and packed onto varying objects. The majority of the catalysts are powdered acids, bases, metal oxides, or metal halides. These substances tend to be highly reactive which can significantly speed up the rate of the reaction making them effective catalysts. [3]
Palladium catalysts can be problematic for the pharmaceutical industry, which faces extensive regulation regarding heavy metals. Many pharmaceutical chemists attempt to use coupling reactions early in production to minimize metal traces in the product. [8] Heterogeneous catalysts based on Pd are also well-developed. [9]