Determination of black carbon in natural organic matter by chemical oxidation and solid-state C-13 Nuclear Magnetic Resonance spectroscopy

Black carbon is an important component of natural organic matter that may play a significant role in global climate change. However, the complexity of natural organic matter has resulted in a milieu of methods and accompanying black carbon values that make it difficult to delineate the proportion of black carbon in soil and sedimentary total carbon budgets, Here we report on a chemical oxidation method that removes lignin and then facilitates black carbon to be estimated from solid-state C-13 Nuclear Magnetic Resonance (NMR) spectroscopy. The resulting black carbon values are lower in comparison to those reported by other researchers but may be a more accurate method for estimating black carbon in a range of natural organic matter samples from different environments. (C) 2004 Elsevier Ltd. All rights reserved.