Nitrogen-Doped Hierarchical Porous Biochar Derived from Corn Stalks for Phenol-Enhanced Adsorption

Abstract

Nitrogen-doped hierarchical porous biochar has aroused great interest in energy storage and adsorption applications. In this study, nitrogen-doped hierarchical porous biochar was prepared from corn stalks by in situ pyrolysis with urea as the nitrogen source and NaHCO 3 as the green activation agent. The liquid adsorption behavior of biochar was evaluated using phenol as a pollutant probe. The results showed that urea had a synergistic effect on the pore structure development of biochar in the presence of an activation agent. The addition of urea especially promoted the formation of micropores. X-ray photoelectron spectroscopy results showed that nitrogen atoms were successfully introduced into the skeleton of biochar in the form of different nitrogen species, which promote the adsorption of phenol. The phenol adsorption was dominated by micropore filling, and the adsorption capacity was positively correlated with the content of graphitic N. The nitrogen-doped biochar obtained at 700 °C with a moderate surface area and a high content of graphite type N exhibited the highest adsorption capacity of phenol. The kinetic analysis also indicates the existence of chemical interactions in the adsorption process.

Sustainable Leaching Process of Phosphates from Animal Bones To Alleviate the World Phosphate Crisis

“…In order to expand experiments to a widely applicable plant biomass source, the former model biomasses (leaves and roots) and the alkaline additive (KOH) in the experiment were replaced by typical waste corn stalks (CS), available in huge amounts as waste about 300 million tons per year in China 41 , and combustion waste alkaline ash (AA) to realize a whole sustainable solid waste starting situation. Since the alkali produced by the action of AA and Ca(OH) 2 is relatively weak, the hydrothermal reaction time was set to 48 h. Even under such real-life conditions, a large amount of P was dissolved (Chicken bone: DP is 15.25 ± 0.92 mg/L, AP is 6.85 ± 1.01 mg/L; Pork bone: DP is 18.08 ± 1.04 mg/L, AP is 2.86 ± 0.04 mg/L), implying that combustion ashes and chalk are suitable candidates to replace KOH.…”

Development of CO2/H2O activated biochar derived from pine pyrolysis: application in methylene blue adsorption

“…AC is characterized by abundant pore structure, strong adsorption capacity and renewability, 17,18 which is of great significance for the treatment of industrial waste liquids and the remediation of environmental pollution 19 . Therefore, it is necessary to improve the surface groups and porous structure of biochar by means of simple operations.…”

The Optimization Parameters of Activated Biochar Derived From Pine Pyrolysis: Application in Methylene Blue Adsorption

“…Among them, the physical adsorption represented by carbon materials has the advantages of simple process, easy operation and recovery, various adsorbents, and no secondary pollution, etc., making it the most promising technical means for industrial application in the filed of water purification (Li et al, 2019a;Xu et al, 2020;Zeng et al, 2018). Activated biochar (AC) is characterized by abundant pore structure, strong adsorption capacity, and renewability (Gao et al, 2013;Genuino et al, 2018), which is of great significant for the treatment of industrial waste liquid and the remediation of environmental pollution (Li et al, 2019b). Choudhary et al (Choudhary et al, 2020) used biochar activated by NaOH to adsorb pollutants in water.…”