Preparation and characterization of high-performance activated carbon from papermaking black-liquor at low temperature

The crude commercial Indulin C kraft lignin (InCL) isolated from pulping black-liquor was used to producing the high-value activated carbon (InCL-AC) with excellent performance. High yields (52.46 %) of InCL-AC with high BET surface area were produced from low cost and unpurified kraft lignin at low temperature (350 °C) using the cheap and environmental-friendly activation agent H3PO4. InCL-AC with higher BET surface areas and larger pore volume than the lignin-based ACs obtained from other commercial lignins, such as Indulin AT (InATL), alkali lignin (AlkL), and Norlig 11D (LS). The adsorption processes of InCL-AC followed the pseudo-second order kinetics with maximum MB adsorption monolayer capacity of 508 mg/g. This approach supplied a potential and effective solution of increasing profit and reducing carbon emissions in pulp production, which is very promising in terms of technical, economic, and environmental feasibilities to transform waste biomass into sustainable feedstocks.