Hydrolysis technology of biomass waste to produce amino acids in sub-critical water

Hydrolysis of biomass waste (such as fish waste, chicken waste, hair and feather) to produce amino acids was studied in sub-critical water, with reaction temperatures from 180 to 320 °C and reaction pressures from 3 to 30 MPa. The product of amino acid was determined by Amino Acid Analyzer (BioLC), and 18 kinds of amino acid were obtained. The results show that the controlling of reaction atmosphere, pressure, temperature and time of hydrolysis is very important to obtain high yield of amino acid; most of amino acids reached maximum yield at reaction temperature range of 200–290 °C and reaction time range of 5–20 min. There are obvious changes of amino acids yield at reaction pressures of 6–16 MPa and reaction temperature around 260 °C, owing to the homogeneousness of the first two phases of water in the formation of vapor and liquid. There are different yields of the same amino acid in different reaction atmospheres (e.g. air, carbon dioxide and nitrogen).