Sunflower feedstocks

In Europe, vegetable-oil-based fuels are mainly produced from rapeseed. In the USA, vegetable-oil-based fuels are mainly derived from soybeans. Another feedstock used in Europe and North America is sunflower seed. Most of the vegetable oil that is used as energy source for the generation of transportation fuel is converted to fatty acid methyl ester (FAME), often called biodiesel . 

For the purposes of making polyols from these triglycerides, oils which contain a high level of unsaturation are desirable. Oils such as soy, canola, and sunflower are acceptable due to relatively low levels of saturated fatty acids, while feedstocks such as palm oil are considered unusable without further purification or refinement due to high levels of saturated fatty acids. Table 1 outlines the composition of several oils (3). 

Kinetic experiments have been reported in literature for the treatment of different types of lipidic feedstock with methanol, such as for soybean [16, 33], rapeseed [25] and sunflower oil [1, 36]. The aim is to optimize the reaction conditions, namely the amount of catalyst, the excess of methanol and the reaction temperature. The results depend largely on the composition of the raw materials, but some trends can be distinguished ... 

Winterizing is not practiced so widely in hot countries and its application is restricted mainly to sunflower, maize, cotton, ohve, ricebran, and partially hydrogenated soybean oils. The feedstock of the winterizing plant is usually bleached oil, sometimes neutralized or deodorized oil. The winterizing process is conducted in four steps ... 

Sunflower oil processing byproducts depend on the kind of refining, whether chemical or physical. The so-called deodistillate of chemical refining of sunflower oil can be used as feedstock for obtaining tocopherols and sterols. The tocopherol composition of sunflower oil (over 90% alpha-tocopherol and only a low proportion of the beta and gamma isomers) makes deodistillates of great value for industrial Vitamin E production. Increased importance has been placed on vegetal sterols because they were found to reduce the risk of cardiovascular disease. As a result, the demand for tocopherols and sterols was increased as food additives. 

Deodistillate originated in physical refining, diluted in free fatty acids, is not an attractive feedstock for Vitamin E and sterol producers. Deodistillate originated in chemical refining of sunflower oil may contain 5-7% of total tocopherols, compared with only 1-2% for deodistillate of physical refining (68). 

Comparisons of the tocopherol and sterol contents from various oils indicate that some oils have appreciably higher contents of specific tocopherols and sterols (94). For example, sunflower is high in a-tocopherol, whereas soybean is higher in y-tocopherol. As deodorization strips tocopherols and sterols from the oil, different feedstock oils yield different concentrations and types of tocopherols. 

Rapeseed oil methyl ester (RME) was the first biodiesel to be developed. Biodiesels based on other feedstocks such as used cooking oil and sunflower oil are now also commercially available. The first pilot plant with a capaeity of 500 tonnes/year was commissioned in 1988 in Austria. The first industrial scale biodiesel production plant went into operation in 1991. Its capacity was 10 000 tonnes/year. In the following years, biodiesel production plants of larger capaeities were established all over Europe, e.g. the plant at Livorno in Italy has a capacity of 80 000 toimes/year. Rouen in France has the world s largest biodiesel production plant with a capacity of 120 000 tonnes/year. Germany and Sweden also have biodiesel production plants of comparable capacities. 

The feedstocks for vegetable oils and fats come from different parts of the world. Soybeans are produced chiefly in the USA, Brazil and China, rapeseed in Europe, Canada, China and India, and sunflowers in East South Europe and Central South America. Palm, coconut and palm kernel oil come from Southeast Asian Countries,... 

Roumanet et al. (2013), used oleic acid from sunflower oil fatty acid as a substrate by lipase epoxidation to produce aliphatic polyesters. The synthesis of polymeric materials based on monomers from renewable feedstock is a... 

Biodiesel is a renewable energy produced from sustainable animal fat and vegetable oil feedstocks, such as soy, rapeseed, sunflowers, palm oil, hemp, and algae, and can be used as a vehicle or transportation fuel. As with ethanol, however, biodiesel is more often used as a diesel additive to reduce the levels of pollution emitted by traditional diesel engines. It is primarily produced through a process known as transesterification, which is the exchange or conversion of an organic acid ester into another ester. 

Othors. Triacylglycerols (triglycerides) (10) (70-72) make up a large part of the storage lipids in animal and plant cells. They are now receiving renewed attention as a candidate feedstock for the production of polymer resins. When liquid at room temperature they are called oils. Commercially important oils are produced from the seeds of soybeans, com (maize), cotton, sunflowers, flax (linseed), rape, castor beans, tung, palms, peanuts, olives, almonds, coconuts, and canola. Over 7.3 million metric tons of vegetable oils are produced in the United States each year, mainly from soybean, flax, and rapeseed. Soy oil alone accounts for 80% of the seed oils produced in the United States. Soy oil contains about 55% linoleic acid (11), 22% oleic acid (12) and 10% palmitic acid (13). 

As mentioned earlier, the quality of the feedstock has a significant effect on the reaction yield, where FFAs and moisture contents are key parameters in defining feedstock feasibility. For example, the alkali-catalyzed production of biodiesel from duck tallow at 65°C and a 6 1 methanol-to-oil molar ratio resulted in a 62% conversion (Chung et al 2009), whereas sunflower resulted in an 86% conversion using the same catalyst under the same conditions (Vicente et al., 2004). 

Biorefineries can be considered to belong to three types. Type 1 biorefineries focus on the conversion of one feedstock, using one process and targeting one product. A biodiesel production plant would be a good example rapeseed or sunflower is used for oil extraction, which is subsequently transesterified to produce fatty acid methyl esters or biodiesel using methanol and a catalyst. 

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