Alcohols biodiesel manufacturing

Fatty acid methyl esters (FAME) are currently manufactured mainly by trans-esterification with an alcohol, using a homogeneous base catalyst (NaOH/KOH). Methanol is more suitable for biodiesel manufacturing, but other alcohols can in principle also be used, depending on the feedstock available. The... 

The last two chapters are devoted to problems of actual interest, manufacturing biofuels from renewable raw materials. Chapter 14 deals with Biodiesel Manufacturing. This renewable fuel is a mixture of fatty acid esters that can be obtained from vegetable or animal fats by reaction with light alcohols. A major aspect in... 

Fatty acid methyl esters and other esters of fatty acids and a lower alcohol can be added at a low ratio to most diesel fuels without substantially changing fuel characteristics. It has been reported that in blends containing 30 percent biodiesel, low-temperature flow properties are not greatly affected (12), but at higher blend levels, the properties of the methyl ester may affect the properties of the fuel. With few exceptions, pure biodiesel does not meet minimum low-temperature requirements and may exceed manufacturers maximum viscosity for diesel fuels. 

It is important to emphasize that all conventional motor fuels—petroleum gasolines and diesel—are produced by complex refining processes. These fuels are mixtures and contain hundreds of organic compounds. None is a single, pure substance. Similarly, almost all biomass-based liquid motor fuels contain numerous organic compounds, but in some cases can consist of relatively few compounds, as in the case of the methyl esters of fatty acids in biodiesel. The exceptions are the lower molecular weight alcohols and a few derivatives that can be used directly as neat motor fuels. They can easily be manufactured from biomass feedstocks as individual compounds. 

Methyl esters of soya, rapeseed and palm oil fatty acids used as biodiesel (Chapters 7 and 8) are preferentially manufactured by transesterification." The acid catalyzed esterification and the alcoholysis of triacylglycerides apply also for the manufacture of higher alcohol monoesters as well as for fatty acid polyol esters. Due to their oily consistency and to their solubilizing properties fatty acid esters of low Mw alcohols are components in odorous substances like perfumes, and cosmetic and drug formulations such as ointments, creams or lotions. 

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