Author(s): Ruben Anillo-Correa | Fredy Colpas-Castillo | Edgardo Meza-Fuentes
Journal: Química Nova
ISSN 0100-4042
Volume: 36;
Issue: 3;
Start page: 387;
Date: 2013;
Original page
Keywords: coal | humic acids | oxidation
ABSTRACT
Low-rank coals are an important source of humic acids, which are important in retention processes of water and nutrients in plants. In this study coal samples of Montelibano, Colombia, were oxidized with air at different temperatures and subsequently with H2O2 and HNO3. The materials were characterized by FTIR, proximate and elemental analysis, and quantification of humic acids. The oxidation process led to an increased content of oxygenated groups and humic acids in the carbonaceous structure. The solid oxidized with air at 200 ºC for 12 h and re-oxidized with HNO3 for 12 h showed the highest percentage of humic acids (85.3%).
Journal: Química Nova
ISSN 0100-4042
Volume: 36;
Issue: 3;
Start page: 387;
Date: 2013;
Original page
Keywords: coal | humic acids | oxidation
ABSTRACT
Low-rank coals are an important source of humic acids, which are important in retention processes of water and nutrients in plants. In this study coal samples of Montelibano, Colombia, were oxidized with air at different temperatures and subsequently with H2O2 and HNO3. The materials were characterized by FTIR, proximate and elemental analysis, and quantification of humic acids. The oxidation process led to an increased content of oxygenated groups and humic acids in the carbonaceous structure. The solid oxidized with air at 200 ºC for 12 h and re-oxidized with HNO3 for 12 h showed the highest percentage of humic acids (85.3%).
