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In chemistry, homogeneous catalysis is catalysis where the catalyst is in same phase as reactants, principally by a soluble catalyst in a solution. In contrast, heterogeneous catalysis describes processes where the catalysts and substrate are in distinct phases, typically solid and gas, respectively. [ 1 ]
Homogeneous catalysts function in the same phase as the reactants. Typically homogeneous catalysts are dissolved in a solvent with the substrates. One example of homogeneous catalysis involves the influence of H + on the esterification of carboxylic acids, such as the formation of methyl acetate from acetic acid and methanol. [27]
Many examples of homogeneous catalysis involving organometallic complexes involve shuttling of complexes between 16- and 18-electron configurations. 16-electron complexes often form adducts with Lewis bases and, if low-valent, undergo oxidative addition. CH 3 I + cis-[Rh(CO) 2 I 2] − → [(CH 3)Rh(CO) 2 I 3] −
The heterogeneous process ultimately failed due to catalyst inactivation and was replaced by the water-based homogeneous system for which a pilot plant was operational in 1958. Problems with the aggressive catalyst solution were solved by adopting titanium (newly available for industrial use) as construction material for reactors and pumps ...
Homogeneous catalysts usually based on complexes of the group 4 metals titanium, zirconium or hafnium. They are usually used in combination with a different organoaluminum cocatalyst, methylaluminoxane (or methylalumoxane, MAO). These catalysts traditionally contain metallocenes but also feature multidentate oxygen- and nitrogen-based ligands. [2]
In chemistry, a phase-transfer catalyst or PTC is a catalyst that facilitates the transition of a reactant from one phase into another phase where reaction occurs. Phase-transfer catalysis is a special form of catalysis and can act through homogeneous catalysis or heterogeneous catalysis methods depending on the catalyst used.
In polymer chemistry, ring-opening metathesis polymerization (ROMP) is a type of chain-growth polymerization involving olefin metathesis. [1] The reaction is driven by relieving ring strain in cyclic olefins. [2] A variety of heterogeneous and homogeneous catalysts have been developed for different polymers and mechanisms. [3]
The Institute carries out basic research in organic and organometallic chemistry, in homogeneous and heterogeneous catalysis as well as in theoretical chemistry.The principal aim is to develop new methods for the selective and environmentally benign preparation of new compounds and materials.