Search

[Display omitted] • A novel Cu/NBC was fabricated by modifying N-doped biochar with Cu MOF-derived Cu. • Cu/NBC exhibited superior desulfurization capacity of 158.28 mg/g at low temperature. • The main desulfurization products of H 2 S were composed of sulfur and copper sulfide. • Desulfurization mechanism involved synergistic catalytic oxidation and adsorption. Hydrogen sulfide (H 2 S) is a highly toxic and corrosive gas that poses significant risks to human health and the environment. Therefore, the development of an adsorbent capable of efficiently purifying H 2 S at room temperature remains a challenging task. In this study, a novel composite adsorbent with a specific surface area of 434 m2·g−1 was fabricated by modifying porous N-doped biochar with Cu nanoparticles (Cu/NBC) derived from Cu-MOFs for low-temperature desulfurization of H 2 S. The effect of pyrolysis temperature and the doping ratio of Cu-MOFs to biochar on the desulfurization performance of H 2 S for the as-prepared Cu/NBC was comprehensively investigated. Experimental results indicated that the desulfurization capability of the optimized Cu/NBC-600-1 adsorbent (synthesized at a pyrolysis temperature of 600 °C and a doping ratio of 1:1) was significantly affected by the desulfurization conditions, and the optimal conditions were determined to be at 25 °C, with 20 % oxygen content and 70 % relative humidity. Under the optimized conditions, the Cu/NBC-600-1 adsorbent exhibited a high H 2 S removal capacity of 158.28 mg·g−1, which was about 3.8 times higher than that of the pristine N-doped biochar. The desulfurization mechanism of the Cu/NBC composite was demonstrated to involve reactive adsorption and catalytic oxidation, resulting in the formation of elemental sulfur and copper sulfides as the main products. This study not only provides a promising approach to modify porous biochar with MOF derivatives, but also offers an effective strategy to remove low concentration H 2 S at room temperature. [ABSTRACT FROM AUTHOR]

[Display omitted] • A MgFe 2 O 4 -loaded and N -doped biochar (MgFe 2 O 4 @NBC) was fabricated by one-pot pyrolysis method. • MgFe 2 O 4 @NBC realized synergistic desulfurization of H 2 S by metal oxide loading and N doping. • MgFe 2 O 4 @NBC delivered superior desulfurization capacity of 1052.83 mg/g at room temperature. • The desulfurization mechanism of H 2 S on MgFe 2 O 4 @NBC was verified by in-situ DRIFTS and XPS. • The desulfurization process of H 2 S was a combination of catalytic oxidation and reactive adsorption. To improve their low-temperature desulfurization performance, the activated carbon-based materials have typically been modified by either metal oxide loading or nitrogen doping. However, most of the aforementioned materials are limited to only one of the above modification methods, resulting in relatively poor desulfurization performance. Herein, a novel MgFe 2 O 4 -loaded N -doped biochar (MgFe 2 O 4 @NBC) was fabricated by one-pot pyrolysis of a nitrogen containing precursor of g-C 3 N 4 , cooked rice waste, and metal salts for efficient low-temperature desulfurization of H 2 S. Different fabrication conditions such as pyrolysis temperature and the nitrogen mixing ratio (i.e., the mass ratio of cooked rice waste to g-C 3 N 4) have been extensively studied. The optimized MgFe 2 O 4 @NBC-500–2 sample delivered a superior breakthrough capacity of 1052.83 mg/g in an atmosphere of O 2 content of 20% and relative humidity of 80% at 25 °C, and demonstrated high tolerance and stability of desulfurization performance to harsh environmental conditions with 80% relative humidity and no oxygen. The desulfurization mechanism of H 2 S on the surfaces of the MgFe 2 O 4 @NBC composites was attributed to the synergistic effects of reactive adsorption and catalytic oxidation process. The composite also demonstrated excellent reusability, retaining 85% of the initial breakthrough capacity after 5 recycled uses. Therefore, the as-prepared MgFe 2 O 4 @NBC composite offers a potentially promising carbon-based desulfurizers for practical applications in the low-temperature desulfurization field. [ABSTRACT FROM AUTHOR]