Evaluation and implementation of methods for quantifying organic and inorganic components of biochar alkalinity

摘要: The Boehm titration, originally developed to characterize carbon blacks and activated carbons, has earned growing attention as a method for characterization of acid base properties biochar (Boehm, 1994; Goertzen et al., 2010). is based on the principle that strong acids bases will react with all acids, respectively, whereas conjugate weak accept protons only from stronger (i.e. lower pKa values). However, distinguish black carbon, including greater solubility higher ash content, may violate integral assumptions titration. Three key are: (1) carbonates (as carbonate bicarbonate) originating atmospheric CO2 are not present during (2) solid-phase reactive compounds, oxides, hydroxides, carbonates, other inorganic such orthophosphate sulfate have been removed prior equilibration reactants, (3) reactants do dissolve significant amounts organic molecules contain functional groups. Here we use three biochars evaluate modified titration methods removing dissolved compounds (DOC) extracts. Our results indicate original measurement groups values > 10.3 reliable when used containing levels or soluble compounds. None Bohem