TY - JOUR

T1 - Ultrasonic Spray Nozzle-Mediated Green Activation for Hierarchical Pore-Structured Carbon Beads

AU - Hough, Michael

AU - Deditius, Artur

AU - Robinson, Neil

AU - Schröder-Turk, Gerd Elmar

AU - Kirkensgaard, Jacob Judas Kain

AU - Gun’ko, Volodymyr M.

AU - Neimark, Alexander V.

AU - Kaneko, Katsumi

AU - Kowalczyk, Piotr

N1 - Publisher Copyright: © 2023 American Chemical Society.

PY - 2024

Y1 - 2024

N2 - This study focuses on enhancing sustainability through energy-efficient methods in producing hierarchically structured porous carbons. A novel approach, utilizing an ultrasonic spray nozzle-quartz tube reactor (USN-QTR), is introduced for fabricating carbon beads with customizable ultra-, super-, and mesopores. This study showcases noteworthy results from subjecting spherical char particles to activation processes involving carbon dioxide, a mixture of carbon dioxide and micron-sized water droplets, and highly concentrated supercritical steam at a temperature of 1173 K for durations of 3 and 5 h. Through pulse-field gradient nuclear magnetic resonance measurements, it was noted that carbon beads produced using USN-generated highly concentrated supercritical steam displayed remarkably elevated intrabead self-diffusivity of n-hexane. Inductively coupled plasma-optical emission spectroscopy demonstrates superior gold recovery kinetics from cyanide solutions compared to that from an industrial benchmark. The energy expenditure for USN-generated steam, producing carbon beads with an apparent surface area of 2691 m2/g, is estimated at 97 J per 1 m2 of carbon. This contrasts with the traditional steam generation method requiring approximately the energy of 190 J/m2 for activated carbon with an SBET of 2130 m2/g, making the USN-assisted activation method a more environmentally friendly and sustainable option with nearly half the energy consumption.

AB - This study focuses on enhancing sustainability through energy-efficient methods in producing hierarchically structured porous carbons. A novel approach, utilizing an ultrasonic spray nozzle-quartz tube reactor (USN-QTR), is introduced for fabricating carbon beads with customizable ultra-, super-, and mesopores. This study showcases noteworthy results from subjecting spherical char particles to activation processes involving carbon dioxide, a mixture of carbon dioxide and micron-sized water droplets, and highly concentrated supercritical steam at a temperature of 1173 K for durations of 3 and 5 h. Through pulse-field gradient nuclear magnetic resonance measurements, it was noted that carbon beads produced using USN-generated highly concentrated supercritical steam displayed remarkably elevated intrabead self-diffusivity of n-hexane. Inductively coupled plasma-optical emission spectroscopy demonstrates superior gold recovery kinetics from cyanide solutions compared to that from an industrial benchmark. The energy expenditure for USN-generated steam, producing carbon beads with an apparent surface area of 2691 m2/g, is estimated at 97 J per 1 m2 of carbon. This contrasts with the traditional steam generation method requiring approximately the energy of 190 J/m2 for activated carbon with an SBET of 2130 m2/g, making the USN-assisted activation method a more environmentally friendly and sustainable option with nearly half the energy consumption.

KW - Energy management

KW - hierarchically porous carbon beads

KW - pulse-field gradient nuclear magnetic resonance

KW - small-angle X-ray scattering

KW - steam activation

KW - ultrasonic spray nozzle

U2 - 10.1021/acssuschemeng.3c04171

DO - 10.1021/acssuschemeng.3c04171

M3 - Journal article

AN - SCOPUS:85181822344

VL - 12

SP - 737

EP - 750

JO - A C S Sustainable Chemistry & Engineering

JF - A C S Sustainable Chemistry & Engineering

SN - 2168-0485

IS - 2

ER -