Abstract: A method for preparing fatty acid alkyl ester for bio-diesels is disclosed, wherein fatty acid, specifically fatty acid distillate reacts with alcohol in the presence of metal catalyst instead of conventional acid or solid acid catalyst. The method does not require the glycerin purification process, and has the superior conversion ratio of fatty acid. The method for preparing fatty acid alkyl ester comprises the step of carrying out an esterification reaction of fatty acid raw material with alcohol in the presence of metal catalyst. Preferably, the esterification reaction is carried out at the temperature of 200 to 350° C. and the pressure of atmospheric pressure to 10 bar, and the metal catalyst is a compound containing metal selected from the group consisting of cobalt, iron, manganese, zinc, titanium and mixture thereof.

Abstract: A method and an apparatus for preparing fatty acid alkyl ester for bio-diesels are disclosed, wherein fatty acid, specifically fatty acid distillate reacts with alcohol, without a catalyst. The method does not require the purification process of the catalyst and glycerin, and has the superior conversion ratio of fatty acid. The method for preparing fatty acid alkyl ester for bio-diesel fuels comprises the step of esterifying fatty acid raw material with alcohol, under a temperature of 200 to 350° C. and a pressure of atmospheric pressure to 10 bar. The apparatus for preparing fatty acid alkyl ester for bio-diesel fuels, comprises: the first reactor for esterifying fatty acid raw material with alcohol under a temperature of 200° C. to 350° C. and a pressure of atmospheric pressure to 10 bar and for converting 80 to 90% of total fatty acid into fatty acid alkyl ester; and the second reactor for converting remaining fatty acid unconverted at the first reactor into fatty acid alkyl ester.

Abstract: The embodiments described herein are directed to providing a multi-column decoder stress test circuit capable of reducing a column stress test time while sufficiently performing a stress test by using column selection signals. The multi-column decoder stress test circuit comprising a control unit configured to receive at least one column test signal and to generate a multi-column enable signal, and a multi-enable decoding unit configured to receive the multi-column enable signal and to generate a plurality of enabled column selection signals.

Abstract: A method for preparing fatty acid alkyl ester for bio-diesels is disclosed, wherein fatty acid, specifically fatty acid distillate reacts with alcohol in the presence of metal catalyst instead of conventional acid or solid acid catalyst. The method does not require the glycerin purification process, and has the superior conversion ratio of fatty acid. The method for preparing fatty acid alkyl ester comprises the step of carrying out an esterification reaction of fatty acid raw material with alcohol in the presence of metal catalyst. Preferably, the esterification reaction is carried out at the temperature of 200 to 350° C. and the pressure of atmospheric pressure to 10 bar, and the metal catalyst is a compound containing metal selected from the group consisting of cobalt, iron, manganese, zinc, titanium and mixture thereof.

Abstract: A method and an apparatus for preparing fatty acid alkyl ester for bio-diesels are disclosed, wherein fatty acid, specifically fatty acid distillate reacts with alcohol, without a catalyst. The method does not require the purification process of the catalyst and glycerin, and has the superior conversion ratio of fatty acid. The method for preparing fatty acid alkyl ester for bio-diesel fuels comprises the step of esterifying fatty acid raw material with alcohol, under a temperature of 200 to 35O0 C and a pressure of atmospheric pressure to 10 bar.