Effect of short-time hydrothermal pretreatment of kitchen waste on biohydrogen production: Fluorescence spectroscopy coupled with parallel factor analysis

The enhancement of bio-hydrogen production from kitchen waste by a short-time hydrothermal pretreatment at different temperatures (i.e., 90 °C, 120 °C, 150 °C and 200 °C) was evaluated. The effects of temperature for the short-time hydrothermal pretreatment on kitchen waste protein conversion and dissolved organic matter characteristics were investigated in this study. A maximum bio-hydrogen yield of 81.27 mL/g VS was acquired at 200 °C by the short-time hydrothermal pretreatment during the anaerobic fermentative hydrogen production. Analysis of the dissolved organic matter composition showed that the protein-like peak dominated and that three fluorescent components were separated using fluorescence excitation–emission matrix spectra coupled with the parallel factor model. The maximum fluorescence intensities of protein-like components decomposed through the parallel factor analysis has a significant correlation with the raw protein concentration, showed by further correlation analysis. This directly impacted the hydrogen production ability.