Allochthonous and autochthonous organic matter in natural waters: Kinetic and thermodynamic patterns of transformation and quantitative and qualitative compositions

Abstract

Using adsorption of organic matter (OM) on diethylaminoethyl cellulose (DEAE-cellulose) in the dynamic mode, OM is divided into autochthonous and allochthonous. Based on the experiments on BOD kinetics and OM division into components, the kinetic parameters of autochthonous and allochthonous OM transformation are established for the first time (k_aut = 0.013, k_all = 0.0013 day^–1 at t =20°C). The activation parameters of transformation for autochthonous OM (ΔH^# = 75.6 kJ/mol, ΔS^# =–116.5 J/(mol K), and ΔG^# = 108.3 J/mol) and allochthonous OM (ΔH^# = 66.1 kJ/mol, ΔS^# =–149.1 J/(mol K), and ΔG^# = 108.0 J/mol) are calculated by the Arrhenius equation.