Natural fatty acid monoglycerides

Besides the examples listed above, a wide range of other compounds with diverse properties can be envisaged using different tail groups other than natural fatty acids and monoglycerides. As an example, alkoxylated alcohols have been esterified with carboxylic acids such as citric acid with potential applications for high-viscosity surfactants in cosmetics [14]. In addition to esters, amides of carboxylic acids linked with lipophilic groups are also known from the patent literature [15]. 

Figure 5.15 GALDI mass spectra of (a) linseed oil (35 years airtight storage from THF solution) and (b) linseed oil as in (a) after 2 weeks of natural ageing (from THF solution). Signal groups of free fatty acids, their oxidation products, and monoglycerides (m/z <500) can be distinguished from diglycerides (m/z 500 800), and triglycerides (m/z 800 1000) (see Table 5.7)...

Fat molecules are characterized as monoglycerides, diglycerides, or triglycerides, depending on whether there are one, two, or three fatty acid chains present in the molecules. Fatty acids in nature generally have an even number of carbon atoms because they are synthesized in cells via successive... 

For biodiesel fuels, the basic idea is to convert natural glycerides to liquid products that have properties closer to those of diesel fuels than those of gasolines. The feedstocks for conversion to biodiesel are usually triglyceride oils from oilseeds. These oils normally contain small amounts of monoglycerides, diglycerides, and free fatty acids. Animal fats and natural non-seed-oil triglycerides are also suitable starting materials. 

The most common method of manufacture involves the hydrolysis of natural vegetable oils such as coconut or palm kernel oil, followed by fractional distillation of the free fatty acids produced. The Cg to Cig fractions are then hydrogenated and reesterified under controlled conditions with glycerin to form a mixture of tri-, di-, and monoglycerides of the required characteristics and hydroxyl value. This process is used for Witepsol. 

The main objective of this work consists in the synthesis of monoglycerides from glycerol and fatty acids issued from vegetable oils in the presence of solid catalysts. Indeed, the use of natural feedstocks presents several advantages i) the diversity of the available products, ii) the renewable character of natural compounds. Moreover, in the chemical industry, the use of natural products opens an area of investigation of new processes and of new products some of which are quite different from those accessible by petrochemical paths. 

The 2-monoglyceride was the main product formed in every case hence the composition of the triglyceride or the nature of die fatty acids split did not affect the pattern of hydrolysis. 

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