Preparation and characterization of lignin-derived nitrogen-doped hierarchical porous carbon for excellent toluene adsorption performance

In order to obtain a low-cost and high-performance solid adsorbent for the removing VOCs, a nitrogen-doped biomass-derived carbon material was synthesized by a facile method of activating nitrogen-doped lignin-char. The influence of the dosage of nitrogen source on the properties of carbon materials was investigated. The obtained NHPC-1 exhibits a large micropore surface area (1554 m(2).g(-1)), a high nitrogen content (4.52 at%/4.47 wt %), and a hierarchical pore structure with the meso-micropores distribution. Owing to these unique characteristics, NHPC-1 exhibits an ultra-high toluene adsorption capacity, up to 934 mg.g(-1) and 1340 mg.g(-1) at 25 degrees C/1185 mg.g(-1) at 30 degrees C, respectively, in both static and dynamic adsorption tests, as well as satisfactory recyclability performance (683 mg.g(-1) after the fifth cycle), and the isotherm can be well fitted by the Langmuir model and Langmuir-Freundlich model. The above excellent adsorption performance reveals that NHPC-1 is a promising candidate for removing VOCs.