Author(s): CERQUEIRA, W. V.; RITTL, T. F.; PINHEIRO, M. A.; PEREIRA NETTO, A. D.; NOVOTNY, E. H.

Summary: Pyrogenic carbon (PyC) has a high potential to soil carbon sequestration. Among the methods used to quantify PyC, the method of benzene polycarboxilic acids (BPCA) is well-established. The oxidation step of this method is essential for a reliable PyC quantification. Up to now there are no studies on the influence of feedstock and pyrolysis temperature in the oxidation kinetic of PyC and BPCA formation; and then these are the purposes of this study. For this, different PyC were oxidised at 170 ºC during different times. The data showed similar kinetic curves for all PyC, but different BPCA production depending upon feedstock and pyrolysis temperature. All PyC showed maximum production of BPCA at 6-8 h under nitric acid oxidation at 170 ºC. We concluded that 8 h of nitric acid oxidation at 170 ºC produces a reliable data to PyC quantification, thus representing a robust method.

Publication year: 2014

Types of publication: Paper in annals and proceedings

Unit: Embrapa Soils

Keywords: Acids, Carbon, Carbono, Cinética de oxidação, Kinetics, Oxidation, Oxidação, Quantificação de carbono pirogênico, biochar, Ácido, Ácido benzenopolicarboxílico