title: Pyrolytic and kinetic characteristics of the thermal decomposition of Perilla frutescens polysaccharide.
abstract: The thermal decomposition of Perilla frutescens polysaccharide was examined by thermogravimetry, differential thermogravimetry, and differential thermal analysis. The results showed that the mass loss of the substance proceeded in three steps. The first stage can be attributed to the expulsion of the water from ambient temperature to 182°C. The second stage corresponded to devolatilization from 182°C to 439°C. The residue slowly degraded in the third stage. The weight loss in air is faster than that in nitrogen, because the oxygen in air accelerated the pyrolytic reaction speed reaction. The heating rate significantly affected the pyrolysis of the sample. Similar activation energies of the degradation process (210-211 kJ mol⁻¹) were obtained by the FWO, KAS, and Popescu techniques. According to Popescu mechanism functions, the possible kinetic model was estimated to be Avrami-Erofeev 20 g(α) = [-ln(1-α)]⁴.
authors.affiliation: School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo, China. zhouquancheng@126.com
authors.forename: Quancheng
authors.initials: Q
authors.lastname: Zhou
authors.forename: Hongmei
authors.initials: H
authors.lastname: Zhang
authors.forename: Guihua
authors.initials: G
authors.lastname: Sheng
mesh_terms: D000465:Algorithms; D003890:Desiccation; D007700:Kinetics; D008956:Models, Chemical; D010084:Oxidation-Reduction; D031344:Perilla frutescens / Q000737:chemistry*; D010936:Plant Extracts / Q000737:chemistry*; D011134:Polysaccharides / Q000737:chemistry*; D013816:Thermodynamics; D013818:Thermogravimetry
chemical_list: D010936:Plant Extracts; D011134:Polysaccharides