Gasification Characteristics of Amino Acids in Supercritical Water

Abstract

The gasification characteristics of five amino acids, i.e., glycine, alanine, valine, leucine, and proline, in supercritical water were compared. A tubular reactor was employed for the gasification reactions in the temperature range of 500 to 650 ℃ with a reaction pressure of 25 MPa and residence time of 86-119 s. The gasification characteristics of glycine, alanine, and leucine were determined to be similar, while the gasification rate of valine was much slower. The activation energies of valine and proline were lower than those of glycine, alanine, and leucine. These behaviors are attributed to the stability of the transition state for carboxyl radical production and secondary radical produced from valine.