Abstract: The present invention relates to methods and apparatus for producing alkyl esters from lipid feed stocks, such as plant oils and/or animal fats, and systems including the same. In an embodiment, the invention includes a process for producing alkyl esters including mixing a lipid feed stock with an alcohol to form a reaction mixture; and contacting the reaction mixture with a catalyst under supercritical conditions for the alcohol, the catalyst comprising an unmodified metal oxide selected from the group consisting of alumina, titania, zirconia, and hafnia, and removing residual free fatty acids from the reaction mixture. Other embodiments are included herein.

Abstract: A device for selectively removing contaminants from a crude product mixture which includes a production reactor for producing a crude oil product mixture, the production reactor includes a lipid reservoir and an alcohol reservoir and a first organic acid removal reactor in fluid communication with the production reactor. The first organic acid removal reactor includes a first housing defining an interior volume the housing configured to receive the crude oil products and disposed within the interior volume of the removal reactor housing is metal oxide media selected from the group consisting of zirconia, alumina, hafnia and titania for removing organic acidic contaminants from the crude oil product to product a purified biodiesel fuel.

Abstract: The present invention relates to systems and methods of using fatty acid alkyl ester solutions to refine feed stocks before converting the feed stocks into fatty acid fatty acid alkyl esters. In an embodiment, the invention includes a method for producing fatty acid alkyl esters. The method can include mixing a crude lipid feed stock with a refining solution to form a crude product mixture, the refining solution comprising greater than about 10 wt. % fatty acid alkyl esters. The method can include extracting the liquid phase from the crude product mixture to obtain a purified lipid feed stock. The method can also include reacting the purified lipid feed stock with an alcohol to form a product mixture comprising fatty acid alkyl esters. In an embodiment, the invention includes a method of making a fatty acid alkyl ester composition.

Abstract: The present invention relates to systems and methods for producing and/or refining alkyl ester compositions. In an embodiment the invention includes a method of producing a refined fatty acid alkyl ester composition. The method can include contacting a fatty acid feedstock and an alcohol with a first metal oxide catalyst at a temperature of greater than 200 degrees Celsius and a pressure of greater than 500 psi to form an unrefined fatty acid alkyl ester composition. The method can further include combining the unrefined fatty acid alkyl ester composition with dimethyl carbonate to form a refining mixture. The method can also include contacting the refining mixture with a second metal oxide catalyst at a temperature of greater than 100 degrees Celsius to form a refined fatty acid alkyl ester composition. Other embodiments are also described herein.

Abstract: The present invention relates to devices and methods for selectively removing contaminants from a crude product mixture. In an embodiment the invention includes a method for removing organic acids from a crude product mixture including contacting the crude product mixture with a metal oxide substrate, wherein free organic acids in the crude product mixture bind to the metal oxide substrate, thereby removing free organic acids and forming a refined product mixture; separating the refined product mixture from the metal oxide substrate; and removing the organic acids bound to the metal oxide substrate by contacting the metal oxide substrate with an alkyl ester composition at a temperature of greater than about 100 degrees Celsius. Other embodiments are also described herein.

Abstract: The present invention relates to systems and methods of using fatty acid alkyl ester solutions to refine feed stocks before converting the feed stocks into fatty acid fatty acid alkyl esters. In an embodiment, the invention includes a method for producing fatty acid alkyl esters. The method can include mixing a crude lipid feed stock with a refining solution to form a crude product mixture, the refining solution comprising greater than about 10 wt. % fatty acid alkyl esters. The method can include extracting the liquid phase from the crude product mixture to obtain a purified lipid feed stock. The method can also include reacting the purified lipid feed stock with an alcohol to form a product mixture comprising fatty acid alkyl esters. In an embodiment, the invention includes a method of making a fatty acid alkyl ester composition.

Abstract: The present invention relates to systems and methods of using fatty acid alkyl ester solutions to refine feed stocks before converting the feed stocks into fatty acid fatty acid alkyl esters. In an embodiment, the invention includes a method for producing fatty acid alkyl esters. The method can include mixing a crude lipid feed stock with a refining solution to form a crude product mixture, the refining solution comprising greater than about 10 wt. % fatty acid alkyl esters. The method can include extracting the liquid phase from the crude product mixture to obtain a purified lipid feed stock. The method can also include reacting the purified lipid feed stock with an alcohol to form a product mixture comprising fatty acid alkyl esters. In an embodiment, the invention includes a method of making a fatty acid alkyl ester composition.

Abstract: The present invention relates to systems and methods for producing and/or refining alkyl ester compositions. In an embodiment the invention includes a method of producing a refined fatty acid alkyl ester composition. The method can include contacting a fatty acid feedstock and an alcohol with a first metal oxide catalyst at a temperature of greater than 200 degrees Celsius and a pressure of greater than 500 psi to form an unrefined fatty acid alkyl ester composition. The method can further include combining the unrefined fatty acid alkyl ester composition with dimethyl carbonate to form a refining mixture. The method can also include contacting the refining mixture with a second metal oxide catalyst at a temperature of greater than 100 degrees Celsius to form a refined fatty acid alkyl ester composition. Other embodiments are also described herein.

Abstract: The present invention relates to methods and apparatus for producing alkyl esters from lipid feed stocks, such as plant oils and/or animal fats, and systems including the same. In an embodiment, the invention includes a process for producing alkyl esters including mixing a lipid feed stock with an alcohol to form a reaction mixture; and contacting the reaction mixture with a catalyst under supercritical conditions for the alcohol, the catalyst comprising an unmodified metal oxide selected from the group consisting of alumina, titania, zirconia, and hafnia, and removing residual free fatty acids from the reaction mixture. Other embodiments are included herein.