Catalysts are widely known in chemistry for facilitating chemical processes. Phase Transfer Catalysts, as the name suggests are sort of catalysts which facilitates migration of reactants from one phase to another phase during chemical reaction. Phase Transfer Catalysts are famous widely for their usability in eco friendly chemical processes. Because When we use Phase Transfer Catalysts we do not need organic solvents. Instead, we can use water as solvent and as results use of organic solvents is reduced. Ionic reactants are not soluble in organic phase in absence of PTCs though they are soluble in water without use of PTC.Sodium carbonate for industrial use are used to facilitate chemical reactions in which participating chemical species are in different phases, generally immiscible liquids or solid and liquid. They enhances the rate of reaction by extracting one of the reactants, most commonly an anion, across the interface into the other phase. And so reaction could easily proceed. Though anion exchange occurs during reactions, catalyst cation is not consumed during process. PTC functions like a detergetnt. They solubalizes salts into organic phase.PTCs are heterogeneous catalysts. i.e. They are use as catalysts in different forms from that of participating reactants. PTCs are quite different than other catalysts. It is not limited upto Hydrophilic and Hydrophobic reactants. It is sometimes used in liquid/solid and liquid/gas reactantions. And due to PTC one of the reactants will be transferred from one phase to another phase at the end of the process.Phase Transfer Catalysts which are used in anionic reactions are typically quarternary ammonium compounds or quarternary phosphonium salts. Typically benzyltrimethylammonium chloride and hexadecyltributylphosphonium bromide. Quarternary Ammonium Compounds, Pyridinium Salts, Methylating Agents, Brominating Agents, And Quarternary Phosphonium Compounds are most widely used and supplied Phase Transfer Catalysts as reffered from γ-butyrolactone Industrially PTC is widely used. For example, we can produce Phosphothioate based pesticides are generated by alkylation process of phosphothioates in presence of PTC. Asymmetric alkylations which are catalyzed by quartarnary ammonium salts derived from cinchomna alkaloids called Chiral. And Acid chlorides and bisphenol-A are used to produce Polyester polymers. Electron-transfer catalysis for Redoxsystems is done using PTC. Metal ion-transfer from aqueous solutionsinto water-immiscible ionic liquids containingneutral complexing agents, Pyrolytic alkylation process, wherebythermal decomposition of a quaternaryammonium salt yields a volatile alkyl derivative in the heated injector of a gas chromatograph is also facilitated with PTC.Choice of suitable PTC for any process will largely depend upon factors like reaction type, solvent, temperature, base strength and ease of catalyst recovery and removal. If these factors are notdecisive, then catalyst cost will determine the choiceMore details on : www.chemsf.com
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