Mono-alkyl esters

One important variable in the transesterification reaction is the molar ratio of reactants. The reaction s stoichiometric ratio requires three moles of alcohol for each mole of TG to produce three moles of mono alkyl ester and one mole of glycerol. In general, the greater the molar ratio, alcohohTG, the higher the conversion for a given time. An alcohol-to-oil molar ratio of 6 1 has been... 

Methyl, propyl, butyl, etc., malonic esters are also obtained in a similar manner. It is to be observed that aryl halides do not undergo this reaction. The di-alkyl esters are obtained from the mono-alkyl esters in the same way as the latter are obtained from malonic ester. But although di-alkyl compounds are not formed directly in any quantity, yet it frequently happens that a little is obtained in the preparation of the mono-alkyl compound from 1 mol. of sodium ethoxide and 1 mol. of alkyl halide, owing to the mono-derivative reacting with more sodium and alkyl halide. This may be prevented when necessary by using only half the calculated quantity of sodium and alkyl halide. By this means the yield of benzoyl malonic ester for example is raised from 55% to 85% in its preparation from sodium, benzoyl chloride and malonic ester. (B., 44, 1507.)... 

The di-alkyl esters are made from the mono-alkyl esters in a manner exactly similar to that by which the mono-alkyl esters are made from acetoacetic ester itself. 

They are a versatile surfactant type, with some properties analogous to those of ether sulphates. Unlike sulphate (which is a sulphuric acid mono alkyl ester), phosphate can form di- and triester, giving a wider range of structures and, with them, the ability to tailor the product to a greater number of application areas. 

When being used as alternative diesel fuel, the mono-alkyl esters of vegetable oils or animal fats are referred to as biodiesel. Biodiesel is playing an... 

The best success and the greatest amount of experience with using vegetable oil in diesel engines has been with transesterification of the oils with simple alcohols to produce mono-alkyl esters, which have viscosities close to No. 2 diesel fuel. Most of the discussion in this chapter will focus on trandesterified fuels, known as biodiesel. 

A modern approach to 15-hydroxypentadecanoic acid comprises fermentation of pentadecane with, for example, Candida tropicalis or Cryptococcus neofor-mans, to yield pentadecanedioic acid [172, 190], the mono-alkyl ester of which may be reduced catalyticaUy under high pressure to the corresponding hydroxy-ester. 

Isomerization of Mono-Alkyl Esters Using Alkali Metal Alcoholates... 

While the suitability of any material as fuel, including biodiesel, can be influenced by contaminants arising from production or other sources, the nature of the major fuel components ultimately determines the fuel properties. Some of the properties included in standards can be traced to the structure of the fatty esters comprising biodiesel. Since biodiesel consists of fatty acid esters, not only the structure of the fatty acids but also that of the ester moiety derived from the alcohol can influence the fuel properties of biodiesel. Furthermore, the aforementioned mono-alkyl esters that comprise biodiesel are a mixture corresponding in its fatty acid profile to that of the parent oil or fat from which it is produced with each ester component contributing to the properties of the fuel. 

The urge to find sustainable replacements for transport fuel has led to a drive to find renewable, nontoxic, and carbon-neutral biofuels. Biodiesel is a fuel composed of mono-alkyl ester derived from vegetables oil or fats oil, which is proven to contribute to reductions in the world s dependence on fossil oils (Mumgesan et al., 2009). The most significant advantages of biodiesel usage over fossil fuel are ... 

Biodiesel = mono-alkyl esters of fatty acids Safe, renewabie, non-toxic, biodegradable Raw materials vegetable oils, fat, recycled grease Positive iife cycie energy balance Positive social impact... 

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