Synthesis and Application of Nanoporous Nitrogen-Doped Carbon from Kraft Lignin

The utilization of renewable resources for the synthesis of advanced materials is of great importance for sustainable development. Lignin is the second most abundant macromolecule in nature and the perfect precursor for the synthesis of various carbon materials due to its high carbon content and aromatic structure. Here, we present a novel approach for the synthesis of nanoporous nitrogen-doped carbon (NNC) from kraft lignin, a widely available waste product from the pulp and paper industry. The synthesis involves a simple process, where kraft lignin is converted into a highly porous carbonaceous material through pyrolysis in a nitrogen atmosphere simultaneously with a nitrogen-doping process using urea as a nitrogen source.<br/><br/>The resulting NNC material exhibits a high surface area (up to 800 m²/g), high nitrogen content and a hierarchical porous structure distributed throughout the material. The NNC material was characterized using various techniques, including XRD, BET, and XPS, to confirm its structural and chemical properties.<br/><br/>NNC was found to have the properties of interest for a number of environmental applications including carbon dioxide capture, adsorption of heavy metals from aqueous solutions and nitrates/nitrites reduction. Overall, the synthesis of NNC from kraft lignin presents a sustainable approach for the development of adsorbents with potential applications in environmental remediation and carbon capture technologies.<br/><br/><b>Acknowledgment:</b> Tetyana M. Budnyak acknowledges financial support from Formas – a Swedish Research Council for Sustainable Development (project: 2020-02321).