306 XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3
in particle sizes and pore structures have a direct impact on
surface area and pore volume. When grinding occurs dur-
ing mixing, particle sizes decrease, leading to an increase in
surface area. Conversely, if pores collapse, the surface area
of pores decreases. Therefore, it is thought that a tradeoff
existed between two opposing factors: particle grinding and
pore collapse. Over brief time intervals (t 16 minutes), the
collapsing effect outweighed the grinding effect, resulting
in a decrease in surface area. Conversely, over longer time
intervals (t 16 minutes), it is believed that the grinding
effect surpassed the collapsing effect, leading to an increase
in surface area. The changes in surface area aligned well
with the conclusions drawn from pore volume changes.
The results indicate a reduction in pore volume over short
time intervals, consistent with pore collapse. Conversely,
there is an increasing trend over longer durations, signify-
ing the dominance of the grinding effect, resulting in finer
particles and consequently more pore volume.
Figure 4 also presents the baseline measurement of the
surface area of hemp biochar before mixing, indicated by
a horizontal dashed line at 12 m2/g. As evident from the
interaction plots, the application of resonant vibratory mix-
ing led to an increase in the surface area of biochar across
nearly all conditions. However, there were particular con-
ditions under which the surface area increase reached its
maximum, achieving an optimized state. For instance,
with a biochar mass of 8.5g in the existing mixing vessel, a
mixing time of two minutes, and an intensity of 75%, the
surface area increase was optimized, as indicated by the tri-
angles in each interaction plot. While the porous structure
of biochar before mixing offers numerous sites where adsor-
bate molecules (CO2) can be attracted and held, expanding
the surface area provides even more space for molecules to
interact and adhere to the surface. Essentially, the expanded
surface area facilitates additional contact points and inter-
action zones between biochar and the target molecules.
Consequently, a greater surface area in biochar results in
an increased number of available adsorption sites, render-
ing it a more efficient adsorbent material. This procedure
enhances the adsorption capability of biochar, improving
its efficiency not just in capturing and holding onto CO2,
but also potentially intensifying the adsorption of rare earth
elements and valuable metals onto biochar. In the next stage
of the research, the resonant vibratory mixing setup will be
further developed as a CCS system, with a focus on quan-
tifying how the improvements in the surface area caused by
LFHA resonant vibrations will impact the parameters asso-
ciated with the adsorption of CO2 onto biochar, aiming to
contribute to the climate targets.
CONCLUSIONS
While most studies on CO2 adsorption onto carbon-based
materials like biochar focus on surface chemistry modifi-
cations, this research introduces LFHA resonant vibra-
tions to enhance CCS technology within the adsorption
process. Using Response Surface Methodology (RSM), we
evaluated the effects of these vibrations on hemp biochar’s
physical properties, especially its surface area, to enhance
CO2 adsorption. Results show that increasing biochar
mass and vibration intensity significantly increases surface
area. However, the mixing time and surface area relation-
ship appears complex, suggesting a tradeoff between par-
ticle grinding and pore structure collapse. Under specific
conditions—8.5g biochar mass, two-minute mixing time,
and 75% intensity—the surface area reaches its highest
increase, maximizing adsorption sites.
REFERENCES
[1] R. Clé and R. Clémençon, “The Two Sides of the
Paris Climate Agreement: Dismal Failure or Historic
Breakthrough?,” vol. 25, no. 1, pp. 3–24, Feb. 2016,
doi: 10.1177/1070496516631362.
[2] S. Yadav and S.S. Mondal, “A review on the progress
and prospects of oxy-fuel carbon capture and seques-
tration (CCS) technology,” Fuel, vol. 308, p. 122057,
Jan. 2022, doi: 10.1016/J.FUEL.2021.122057.
[3] T. Guo et al., “Characteristics of CO2 adsorption on
biochar derived from biomass pyrolysis in molten
salt,” Can J Chem Eng, vol. 96, no. 11, pp. 2352–
2360, Nov. 2018, doi: 10.1002/CJCE.23153.
[4] R.G. Tailleur, “Scientific Bases for the Preparation
of Heterogeneous Catalysts -Proceedings of the
8th International Symposium, Louvain-la-Neuve,
Belgium 9–12, 2002,” Stud Surf Sci Catal, vol.
143, pp. 321–329, 2000, Accessed: May 30, 2023.
[Online]. Available: http://www.sciencedirect.com
/science/article/pii/S0167299100806710
[5] B. Dutcher, M. Fan, and A.G. Russell, “Amine-based
CO2 capture technology development from the begin-
ning of 2013-A review,” ACS Appl Mater Interfaces,
vol. 7, no. 4, pp. 2137–2148, Feb. 2015, doi: 10.1021/
AM507465F/ASSET/IMAGES/LARGE/AM-2014
-07465F_0001.JPEG.
[6] J. Beiyuan, Y.M. Awad, F. Beckers, D.C.W. Tsang,
Y.S. Ok, and J. Rinklebe, “Mobility and phy-
toavailability of As and Pb in a contaminated
soil using pine sawdust biochar under system-
atic change of redox conditions,” Chemosphere,
vol. 178, pp. 110–118, Jul. 2017, doi: 10.1016
/J.CHEMOSPHERE.2017.03.022.
in particle sizes and pore structures have a direct impact on
surface area and pore volume. When grinding occurs dur-
ing mixing, particle sizes decrease, leading to an increase in
surface area. Conversely, if pores collapse, the surface area
of pores decreases. Therefore, it is thought that a tradeoff
existed between two opposing factors: particle grinding and
pore collapse. Over brief time intervals (t 16 minutes), the
collapsing effect outweighed the grinding effect, resulting
in a decrease in surface area. Conversely, over longer time
intervals (t 16 minutes), it is believed that the grinding
effect surpassed the collapsing effect, leading to an increase
in surface area. The changes in surface area aligned well
with the conclusions drawn from pore volume changes.
The results indicate a reduction in pore volume over short
time intervals, consistent with pore collapse. Conversely,
there is an increasing trend over longer durations, signify-
ing the dominance of the grinding effect, resulting in finer
particles and consequently more pore volume.
Figure 4 also presents the baseline measurement of the
surface area of hemp biochar before mixing, indicated by
a horizontal dashed line at 12 m2/g. As evident from the
interaction plots, the application of resonant vibratory mix-
ing led to an increase in the surface area of biochar across
nearly all conditions. However, there were particular con-
ditions under which the surface area increase reached its
maximum, achieving an optimized state. For instance,
with a biochar mass of 8.5g in the existing mixing vessel, a
mixing time of two minutes, and an intensity of 75%, the
surface area increase was optimized, as indicated by the tri-
angles in each interaction plot. While the porous structure
of biochar before mixing offers numerous sites where adsor-
bate molecules (CO2) can be attracted and held, expanding
the surface area provides even more space for molecules to
interact and adhere to the surface. Essentially, the expanded
surface area facilitates additional contact points and inter-
action zones between biochar and the target molecules.
Consequently, a greater surface area in biochar results in
an increased number of available adsorption sites, render-
ing it a more efficient adsorbent material. This procedure
enhances the adsorption capability of biochar, improving
its efficiency not just in capturing and holding onto CO2,
but also potentially intensifying the adsorption of rare earth
elements and valuable metals onto biochar. In the next stage
of the research, the resonant vibratory mixing setup will be
further developed as a CCS system, with a focus on quan-
tifying how the improvements in the surface area caused by
LFHA resonant vibrations will impact the parameters asso-
ciated with the adsorption of CO2 onto biochar, aiming to
contribute to the climate targets.
CONCLUSIONS
While most studies on CO2 adsorption onto carbon-based
materials like biochar focus on surface chemistry modifi-
cations, this research introduces LFHA resonant vibra-
tions to enhance CCS technology within the adsorption
process. Using Response Surface Methodology (RSM), we
evaluated the effects of these vibrations on hemp biochar’s
physical properties, especially its surface area, to enhance
CO2 adsorption. Results show that increasing biochar
mass and vibration intensity significantly increases surface
area. However, the mixing time and surface area relation-
ship appears complex, suggesting a tradeoff between par-
ticle grinding and pore structure collapse. Under specific
conditions—8.5g biochar mass, two-minute mixing time,
and 75% intensity—the surface area reaches its highest
increase, maximizing adsorption sites.
REFERENCES
[1] R. Clé and R. Clémençon, “The Two Sides of the
Paris Climate Agreement: Dismal Failure or Historic
Breakthrough?,” vol. 25, no. 1, pp. 3–24, Feb. 2016,
doi: 10.1177/1070496516631362.
[2] S. Yadav and S.S. Mondal, “A review on the progress
and prospects of oxy-fuel carbon capture and seques-
tration (CCS) technology,” Fuel, vol. 308, p. 122057,
Jan. 2022, doi: 10.1016/J.FUEL.2021.122057.
[3] T. Guo et al., “Characteristics of CO2 adsorption on
biochar derived from biomass pyrolysis in molten
salt,” Can J Chem Eng, vol. 96, no. 11, pp. 2352–
2360, Nov. 2018, doi: 10.1002/CJCE.23153.
[4] R.G. Tailleur, “Scientific Bases for the Preparation
of Heterogeneous Catalysts -Proceedings of the
8th International Symposium, Louvain-la-Neuve,
Belgium 9–12, 2002,” Stud Surf Sci Catal, vol.
143, pp. 321–329, 2000, Accessed: May 30, 2023.
[Online]. Available: http://www.sciencedirect.com
/science/article/pii/S0167299100806710
[5] B. Dutcher, M. Fan, and A.G. Russell, “Amine-based
CO2 capture technology development from the begin-
ning of 2013-A review,” ACS Appl Mater Interfaces,
vol. 7, no. 4, pp. 2137–2148, Feb. 2015, doi: 10.1021/
AM507465F/ASSET/IMAGES/LARGE/AM-2014
-07465F_0001.JPEG.
[6] J. Beiyuan, Y.M. Awad, F. Beckers, D.C.W. Tsang,
Y.S. Ok, and J. Rinklebe, “Mobility and phy-
toavailability of As and Pb in a contaminated
soil using pine sawdust biochar under system-
atic change of redox conditions,” Chemosphere,
vol. 178, pp. 110–118, Jul. 2017, doi: 10.1016
/J.CHEMOSPHERE.2017.03.022.