Sorbitan esters synthesis

In the enzymatic process utilized herein for the production of fatty acid methyl ester fixrm rapeseed oil, several factors are known to influence conversion. The initial step of this study involved the identification of factors likely to influence conversion, fri this study, tert-butanol was applied in lipase-catalyzed methanolysis. fert-Butanol has been utilized previously in several enzymatic process, including sorbitan ester synthesis [6, 15]. It has also been confirmed that terf-butanol is inert in the Novozym 435-catalyzed methanolysis of rapeseed oil for the production of biodiesel [12]. 

Sarney, D.B., M.J. Barnard, M. Virto, and E.N. Vulfson, Enzymatic Synthesis of Sorbitan Esters Using a Low-Boiling-Point Azeotrope as a Reaction Solvent, Ibid. 54 351-356(1997). 

Samey, D. B., Barnard, M. J., Virto, M., and Vulfson, E. N., Enzymatic synthesis of sorbitan esters using a low-boiling-point azeotrope as a reaction solvent, Biotechnol. Bioeng., 54, 351-356, 1997. 

Figure 9.2.11 Sorbitan esters and polysorbates synthesis scheme.

There is on record at least one investigation leading to the emulsion synthesis of YBa2Cu307 x powders [207]. The basic solvent system was Tween 85, poly(oxyethylene) sorbitan ester/kerosene (oil phase). The aqueous phase containing dissolved salts Ba(N03)2, Cu(N03)2.3H20 and Y(N03)3.H20 in proper proportions was added into the surfactant/oil system under stirring which was continued for several hours after the addition was complete. An ultrasonic disruptor was used for decreasing the aqueous droplet size. This emulsion was added drop by drop into hot (180"C) kerosene. The product powders were washed with toluene... 

Figure 7.21 Synthesis of sorbitan esters by intramolecular dehydration of sorbitol in the presence of an acid at 150-200°C and subsequent base-catalyzed esterification with fatty acids at 200-250°C.

Smidrkal J., Cervenkova R., Filip V, Two-stage synthesis of sorbitan esters, and physical properties of the products, Eur. J. Lipid Sci. TechnoL, 106(12), 2004, 851-855. 

These are just a few of the many chemical reactions of the hexoses. Gluconic acid, glucono-5-lactone from this acid, sorbitol, sorbitol esters, sorbitans (tetra-hydric anhydrosorbitol), mannitol, mannitol esters, copolymers of fatty acid sorbitol esters and alkylene oxides, and a few other derivatives are currently marketed as commodity chemicals derived from the hexoses. Vitamin C (l-ascorbic acid) is perhaps one of the best examples of a commercial derivative of D-glucose that is manufactured primarily by chemical synthesis ... 

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