Supercritical fluid chemical reaction
With the development of supercritical CO2 fluid extraction technology, people have given supercritical fluid reaction (SFR) with great attention, the particularity observed in the supercritical CO2 fluid extraction test can be used in supercritical fluid eaction.
Supercritical fluid medium can replace organic solvents, thereby reducing the environmental pollution caused by organic solvents.
Advantages of Supercritical fluid chemical reaction
The chemical reaction in supercritical fluid has the following advantages:
- Reduce the reaction temperature of high-temperature reactions;
- Improve the reaction rate, selectivity and yield
- Extend the activity of the heterogeneous catalytic reaction catalyst;
- Reduce the reaction phase or make the reaction proceed in a homogeneous phase;
- It is expected to realize the integration of reaction and separation;
- No environmental pollution.
Enzyme catalyzes the reaction
- Supercritical fluid reaction is significantly improved compared with traditional methods in terms of reaction speed, reaction temperature, conversion rate of reactants, yield of products, catalyst activity, life span and separation of products.
- Enzyme-catalyzed reactions are characterized by mild reaction conditions, high catalytic activity and good stereoselectivity.
- They are often used in drug synthesis, fine chemical synthesis, and the synthesis and resolution of chiral compounds.
Due to the particularity of biological processes, enzyme-catalyzed reactions are applications are greatly restricted. Studies have shown that enzymes have good catalytic activity in supercritical fluid , and supercritical CO2 can replace organic solvents as non-aqueous media
- In the supercritical CO2 system, the lipid-soluble reactants and products with low polarity can be dissolved in it, which greatly increases the reaction speed.
- At the same time, the catalyst enzyme is insoluble in the system and easy to separate.
- In this way, it can avoid the instability of enzymes in the aqueous medium and the low solubility of the reaction materials, and solve the problems of expensive organic solvents and residues in the synthesis process of organic solvents, especially environmental pollution.
In short, some enzyme-catalyzed reactions under supercritical conditions overcome the shortcomings of reactions in the aqueous and organic phases, especially lipase-catalyzed reactions, which can obtain chiral compounds with biological activity with high selectivity.
At present, the main types of supercritical enzyme-catalyzed reactions are hydrolysis, alcoholysis, acidolysis and oxidation.