Biodiesel ethyl ester

Bioethanol is suitable for internal combustion engines that run on gasoline. Similarly, biodiesel is designed for diesel engines. Biodiesel is a fuel manufactured from various oils and fats. These acids are chemically transformed to fatty acid methyl esters. By blending the fatty acid methyl or ethyl esters in the right proportions, the properties of the fuel can be influenced [59] and potentially mimic the properties of petrochemically derived diesel. Biofuel efficiency generally is the same as for fossil-derived diesel fuel [59]. 

To improve the cold properties of biodiesel, the use of alcohol with longer alkyl chain has been studied in the alkaline-catalyzed method. The cloud point for ethyl esters is approx 2°C lower than that of the corresponding methyl esters, while butyl esters are 10°C lower than methyl esters (6). Furthermore, cetane number is appropriate for alkyl esters from the alcohol with the longer alkyl chain (7). 

Table 2 presents cloud and pour points of biodiesel prepared by our supercritical alcohol method at 350°C. For comparison, the results of the commercial biodiesel fuels are also shown. These results demonstrate that the cloud point of ethyl esters was 3°C lower than that of methyl esters, while that of butyl esters was even lower. The cloud point of methyl ester was similar to that of commercial biodiesel fuels. 

Shrestha et al (2005) conducted a study in which SME, mustard seed oil methyl and ethyl esters and used peanut oil methyl esters were blended (B0, B5 and B10) with No. 2 petrodiesel and treated with six commercial petrodiesel CFI additives. It was found that at 100, 200, and 300% of the specified loading rate, CP and PP were reduced by an average of 2.2 °C and 14.1 °C, respectively. Mustard seed oil ethyl esters exhibited the highest average reduction in CP and PP and SME exhibited the lowest, as shown by Table 1.9 for CP. Furthermore, a significant decrease in CP was noticed when additive concentration was increased from 100% of the specified loading rate to 200% however, the difference between 200% and 300% was not significant. The authors conclude that the effect of fuel additive is not only different for different feedstocks but also some fuel additives worked better for a specific blend of biodiesel with No. 2 petrodiesel. 

MEE = mustard seed oil ethyl esters MME = mustard seed oil methyl esters UPEME = used peanut oil methyl esters B5 = 5vol% biodiesel in No. 2 petrodiesel blends B20 and B100 are defined in Tables 1.4 and 1.6. See Tables 1.2 and 1.3 for other abbreviations. 

Scheme 7.1. Base-catalyzed transesterification of triacylglycerols (TAGs) to produce fatty acid esters (biodiesel). Methyl esters (shown) are the most common but others, such as ethyl esters, can be produced depending on the alcohol used in the reaction. Ri, R2 and R3 represent unique fatty acids attached to the glycerol backbone of the TAG.

In most parts of the world, the term biodiesel now denotes a diesel fuel that is produced by converting a vegetable oil to methyl (or ethyl) esters. In the United States soybean oil has been the primary feedstock for biodiesel, mainly becase it is commonly the least expensive and most abundant vegetable oil. Although there are economic reasons why corn oil (and other U.S. vegetable oils) has not been used as feedstocks for biodiesel, there are no technical reasons why a corn oil biodiesel could not be successfully developed (personal communication. M. Haas). 

Methyl and ethyl esters of fatty acids have been used in consumer products for a long time and are generally recognized as safe in specific applications (23, 24). However, the new use of biodiesel as a fuel has led to tests to determine its potential toxicity in new applications. 

Rainbow trout survived 48 hours of treatment with 100 ppm and 300 ppm canola methyl and ethyl esters, but were in poor condition (25). Biodiesel exhibits acute toxicity in aquatic systems but its rapid degradation and low overall toxicity make it greatly preferred to diesel fuel in environmentally sensitive areas. 

Biodiesel fuel can be produced from jatropha oil using a fairly simple chemical reaction known as trans-esterification. In this process, the oil reacts with a simple alcohol (methanol/ethanol) in the presence of a catalyst (caustic soda/potash) and, under specified conditions such as a temperature of 65°C and normal atmospheric pressure, yields a mixture of methyl or ethyl esters which is the biodiesel. This fuel... 

Biodiesel is made up of the methyl or ethyl esters of fatty acids, and is obtained from the triglycerides found in vegetable oils through the well-known transesterification reaction (Scheme 1). 

As both methyl and ethyl alkyl esters are considered biodiesel, the enzymatic transesterification of soybean oil with ethanol was studied in this work. In Brazil, the production of ethyl esters is a sustainable technology, as ethanol can be easily produced from fermentable sugar (biomass). 

Biodiesel, i.e., fatty add methyl or ethyl ester from rapeseed, soybeans, sunflowers or palm oil waste oils, e.g from food... 

The fatty acid methyl/ethyl esters of vegetable oils such as jatropha, Mesua ferrea, soybean, rapeseed, cottonseed, sunflower, safflower, peanut and linseed can be used as an alternative fuel for diesel engines (biodiesel) Methyl and ethyl esters of vegetable oils have several outstanding advantages among other new renewable and clean engine fuel alternatives. The... 

Vegetable oils (such as rapeseed, soybean and palm oils) or animal fats (beef tallow) are used for the production of so-called biodiesel, which is typically made by alcoholysis of oils and fats with methanol, ethanol or propan-l-ol. With the growth in the hydrocarbon chain length of the alcohol, the lipophilicity increases so that the two-phase system does not form in the reaction with propan-l-ol, and glycerol does not separate. Therefore, the industrially important esters, such as propyl or butyl esters as well as esters of secondary alcohols, can be only prepared by direct esterification of fatty acids with the appropriate alcohol. Methyl and especially ethyl esters can also be obtained by enzyme-catalysed alcoholysis using non-specific lipases. 

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