Catalysis

thumb|400px|The enzyme glucosidase converts the sugar [[maltose into two glucose sugars. Active site residues in red, maltose substrate in black, and NAD cofactor in yellow. ()|alt=Ribbon diagram of glycosidase with an arrow showing the cleavage of the maltose sugar substrate into two glucose products.]]

thumb|Phylogenetic tree of bacteria and archaea, highlighting those that carry out fermentation. Their end products are also highlighted. Figure modified from Hackmann (2024). Fermentation is a type of anaerobic metabolism that harnesses the redox potential of the reactants to make adenosine triphosphate (ATP) and organic end products. Organic molecules, such as glucose or other sugars, are catabolized and their electrons are transferred to other organic molecules (cofactors, coenzymes, etc.). Anaerobic glycolysis is a related term used to describe the occurrence of fermentation in organisms (

thumb|A range of industrial catalysts in pellet form thumb|An air filter that uses a low-temperature oxidation catalyst to convert [[carbon monoxide to less toxic carbon dioxide at room temperature. It can also remove formaldehyde from the air.]] Catalysis (, ) is the increase in rate of a chemical reaction due to an added substance known as a catalyst ( ). Catalysts are not consumed by the reaction and remain unchanged after the reaction. If the reaction is rapid and the catalyst is recycled quickly, a very small amount of catalyst often suffices; mixing, surface area, and temperature are imp

thumb|Brunauer, Emmett, and Teller's #BET|model of multilayer adsorption is a random distribution of molecules on the material surface.

artificial nitrogen fixation process which is the main industrial procedure for the production of ammonia nowadays

energy that must be input to a system to undergo a reaction or process

type of unsaturated fat that occurs in small amounts in nature, but is also produced industrially from vegetable fats for use in foods

Catalase is a common enzyme found in nearly all living organisms exposed to oxygen (such as bacteria, plants, and animals) which catalyzes the decomposition of hydrogen peroxide to water and oxygen. It is a very important enzyme in protecting the cell from oxidative damage by reactive oxygen species (ROS). Catalase has one of the highest turnover numbers of all enzymes; one catalase molecule can convert millions of hydrogen peroxide molecules to water and oxygen each second.

molecule upon which an enzyme acts

emission control device that treats engine exhaust gas by catalyzing pollutant-destroying redox reactions

substance that decreases the rate of, or prevents, a chemical reaction

active site of an enzyme; region of an enzyme where substrate molecules bind and undergo a chemical reaction to form products

chemical reactions that convert carbon monoxide and hydrogen into liquid hydrocarbons

Model of enzyme kinetics

study of biochemical reaction rates catalysed by an enzyme

A chemical reaction is autocatalytic if one of the reaction products is also a catalyst for the same reaction. Many forms of autocatalysis are recognized.

chemical process for producing nitric acid from ammonia and oxygen

catalysis of chemical reactions by specialized proteins known as enzymes

type of reaction in organic chemistry

methanation process of carbon dioxide with hydrogen

type of catalysis where the reactants and catalysts are different phases of matter

contact process is a method to prepare sulphuric acid / oil of vitriol in industrial cases.

thumb|In the experiment above, photons from a light source (out of frame on the right hand side) are absorbed by the surface of the titanium dioxide () disc, exciting electrons within the material. These then react with the water molecules, splitting it into its constituents of hydrogen and oxygen. In this experiment, chemicals dissolved in the water prevent the formation of oxygen, which would otherwise recombine with the hydrogen.

thumb|300px| Justus von Liebig's synthesis of [[oxamide from dicyan and water represents the first organocatalytic reaction, with acetaldehyde further identified as the first discovered pure "organocatalyst", which act similarly to the then-named "ferments", now known as enzymes.]]

method for producing hydrogen, carbon monoxide, or other useful products from hydrocarbon fuels

Strongly oxidizing solution of hydrogen peroxide mixed with dissolved iron as catalyst

lighter invented in 1823 by J. W. Döbereiner

Set of three coordinated amino acids

dimensionless numbers used in chemical engineering

chemical reaction

multistep reaction mechanism that involves a catalyst

Calcium oxide rehydrated with a solution of sodium hydroxide

Scottish chemist

chemical process

method of production of liquid hydrocarbons for use as synthetic fuel

thumb|Three dimensional structure of an enzyme. Biocatalysis utilizes these biological macromolecules to catalyze small molecule transformations. Biocatalysis refers to the use of living (biological) systems or their parts to speed up (catalyze) chemical reactions. In biocatalytic processes, natural catalysts, such as enzymes, perform chemical transformations on organic compounds. Both enzymes that have been more or less isolated and enzymes still residing inside living cells are employed for this task. Modern biotechnology, specifically directed evolution, has made the production of modified

Chemical reaction with peroxides catalysed by Fe(III/II)

an aqueous ammonia SCR process overview

catalysis in a solution by a soluble catalyst

industrial process historically used to produce sulfuric acid

chemical process

chemical process

chemistry concept

Enzyme rate limited by diffusion

Expansive chemical reaction damaging concrete

German chemist (1870–1939)

Coking is the process of heating coal in the absence of oxygen to a temperature above to drive off the volatile components of the raw coal, leaving behind a hard, strong, porous material with a high carbon content called coke. Coke is predominantly carbon. Its porous structure provides a high surface area, allowing it to burn more rapidly, much like how a bundle of tinder burns faster than a solid wooden log. As such, when a kilogram of coke is burned, it releases more heat than a kilogram of the original coal.

Chemisorption is a kind of adsorption which involves a chemical reaction between the surface and the adsorbate. New chemical bonds are generated at the adsorbent surface. Examples include macroscopic phenomena that can be very obvious, like corrosion, and subtler effects associated with heterogeneous catalysis, where the catalyst and reactants are in different phases. The strong interaction between the adsorbate and the substrate surface creates new types of electronic bonds.

class of chemical reactions

material engineered to automatically repair physical damage without any human intervention

In organic chemistry, hydrocyanation is a process for conversion of alkenes to nitriles. The reaction involves the addition of hydrogen cyanide and requires a catalyst if the substrate alkene is unactivated. This conversion is conducted on an industrial scale for the production of precursors to nylon. Direct hydrocyanation is rare in the laboratory because hydrogen cyanide is extremely toxic, but transfer variants can allow other nitrilic compounds to serve as hydrogen cyanide synthons.

Chemical reaction

process for the production of hydrogen peroxide

chemical compound

Empirical model for microorganisms growth

dimensionless parameter that compares the rate of reaction in a liquid film to the rate of diffusion through the film

chemical process

thumb|175px|A platinum cathode electrocatalyst's stability being measured by chemist Xiaoping Wang

Cuprospinel is a mineral. Cuprospinel is an inverse spinel with the chemical formula CuFe2O4, where copper substitutes some of the iron cations in the structure. Its structure is similar to that of magnetite, Fe3O4, yet with slightly different chemical and physical properties due to the presence of copper.