Summary
This study focused on spectroscopic characterization of slow pyrolysis distillates from three different hemp hurd variates of industrial hemp (Cannabis sativa L). Raw distillates were collected at drying, torrefaction and pyrolysis stage of the slow pyrolysis process starting from room temperature up to the maximum operating temperature of 350 °C. Complementary chemical characterization of the hemp hurd distillate fractions was achieved using Fourier transform infrared (FTIR) spectroscopy, 1D and 2D NMR spectroscopy, comprehensive two-dimensional gas chromatography-mass spectrometry (2D GC–MS) and liquid chromatography–high resolution mass spectrometry (LC–HRMS). These analyses provided information on the concentration of main chemical constituents of distillates, detected valuable, volatile, semivolatile and nonvolatile compounds and their chemical nature as indicated by functional groups. This study reveals the possibility of optimizing the use of hemp hurds as high-value products by utilizing slow pyrolysis for biochar and further processing for distillates.
