Ion exchange resins and immobilized lipase as heterogeneous catalysts are used to synthesize biodiesel for alternative fossil fuels. The use of ion in the solid activated phase can ease separation process. Furthermore, be reactivated repeatedly, reducing need catalysts. On other hand, an enzyme is biodegradable catalyze transesterification process produce with a lower alcohol-to-oil ratio, mini...

Transesterification, one of the most effective methods for ester synthesis, is usually conducted under acid or basicconditions. Although quite a few methods have been reported for transesterification, they are not general as far asp-ketoesters are concerned. Some of these methods used toxic, expensive reagents and in relatives large amount. Inthis research, transesterification reaction six type...

Due to the high price of virgin vegetable oils and the drawbacks of the homogeneous catalytic transesterification, in this work an economically profitable alternative process was proposed for biodiesel synthesis in which transesterification of the low-cost waste cooking oil (WCO) with methanol in a heterogeneous system was done. Alumina impregnated with sodium hydroxide was utilized as a solid ...

The synthesis of four new peptidyl nucleosides is reported. The kinetic data obtained for the transesterification of 2'/3'-O-benzyloxycarbonyl-L-p-nitrophenylalanyl 5'-O-trityl ribonucleosides which contain different substituents at C position of the purine residue indicates for different mechanisms of the transesterification reaction. The peptidyl nucleosides with an amino group at C position ...

Cooking oil waste leads to well-known environmental impacts and its bioremediation by lipase-based enzymatic activity can minimize the high cytotoxic potential. In addition, they are among the biocatalysts most commercialized worldwide due to the versatility of reactions and substrates. However, although lipases are able to process cooking oil wastes, the products generated from this process do...

Biodiesel production is worthy of continued study and optimization of production procedures due to its environmentally beneficial attributes and its renewable nature. Heterogeneous transesterification is considered to be a green process. The process requires neither catalyst recovery nor aqueous treatment steps and very high yields of methyl esters can be obtained, close to the theoretical valu...

Kinetic study of methanolysis of rapeseed oil in two phase liquid-liquid systems is performed in a batch reactor observing substances concentration gradient for process optimization. Concentration of initial substances, temperature of the system and stirring speed have significant effect on transesterification of rapeseed oil. They are considered as dominant factors to be optimized. Transesteri...

Nowadays microwave radiation is being researched to produce biodiesel from different raw materials due to the many advantages that this technology presents compared to traditional transesterification, such as shorter reaction times and less amount of heat energy to obtain biodiesel. The aim of this research was to explore the possibility of carrying out the microwave-assisted transesterificatio...

Subtilisin and alpha-chymotrypsin vigorously act as catalysts in a variety of dry organic solvents. Enzymatic transesterifications in organic solvents follow Michaelis-Menten kinetics, and the values of V/Km roughly correlate with solvent's hydrophobicity. The amount of water required by chymotrypsin and subtilisin for catalysis in organic solvents is much less than needed to form a monolayer o...