Home – Home – Jornals – Chemistry for Sustainable Development 2023 number 1

Extraction processing of pine needles ( Pinus sylvestris Ledeb.) allows obtaining the products that are used to manufacture the goods in medical, food, perfumery and cosmetics, and other branches of industry. At the same time, the post-extraction residue of needles (PERN), being a specific lignocellulose raw material, has not yet found proper (effective) use for obtaining innovative products. Using the method of thermogravimetry in a nitrogen atmosphere (TG/DTG), a number of thermal decomposition patterns of PERN have been established. Based on the results of TG/DTG, the kinetics of PERN pyrolysis was analyzed, the thermodynamic parameters Δ H , Δ G and Δ S were calculated. The average values of Δ H , Δ G and Δ S are 246.3, 160.3 kJ/mol and 135.7 J/(mol · K), respectively. According to the method of the fourth derivative of DTG contour proposed by us, a detailed “fractionality” of mass loss during heating of PERN under the conditions of thermogravimetric test has been established. The values of the apparent rate constant are calculated, indicating the multistage (I-V) process of thermal decomposition. By means of analytical flash pyrolysis of PERN, 66 pyrolysis products were identified. Among them, 35 compounds were identified that are not found in pine bark and wood pyrolyzates and can be in demand in organic synthesis, in the production of technical and food products, perfumes, medical products, etc . The obtained results are basic for designing the manufacture of technical products with increased added value and scaling of heat treatment technologies and pyrolysis of similar plant raw materials.