CO2 capture using biochar derived from municipal residual sludge conditioned with chitosan

doi:10.21203/rs.3.rs-4943411/v1

Download PDF

Research Article

CO2 capture using biochar derived from municipal residual sludge conditioned with chitosan

https://doi.org/10.21203/rs.3.rs-4943411/v1

This work is licensed under a CC BY 4.0 License

Version 1

posted

You are reading this latest preprint version

To achieve the dual objectives of pollution reduction and carbon mitigation, this study examined the effects of biochar derived from urban residual sludge conditioned with chitosan (SBCC) on the CO₂ capture capacity. Using raw sludge biochar (RSB) as the control group, and focusing on the preparation temperature of the biochar and the adsorption temperature of CO₂ as main parameters, the study explored the CO₂ adsorption performance of modified sludge biochar. The mechanism of CO₂ adsorption by SBCC was elucidated through the analysis of the surface morphology, elemental composition, functional groups, and surface area of the sludge biochar. Results indicate that the optimal preparation and adsorption temperatures for RSB are 800°C and 30°C, respectively, with a maximum CO₂ adsorption capacity of 28.36 mg/g. For SBCC, the optimal temperatures are 600°C and 30°C, respectively, achieving a maximum CO₂ adsorption of 89.88 mg/g. Compared to RSB, SBCC primarily exhibits a chemisorption process, with its adsorption mechanism involving strong dipole-quadrupole interactions between nitrogen atoms and CO₂. In the sludge, chitosan undergoes partial hydrolysis through alkalinization, forming carboxyl groups. These carboxylic functional groups facilitate the formation of hydrogen bonds between CO₂ and the carbon surface, as well as condensation reactions between alkaline functional groups and CO₂. Moreover, SBCC also demonstrates good reusability. After five cycles of adsorption and desorption, it still retains up to 75% of its initial CO₂ adsorption capacity.

CO2 capture

Municipal residual sludge

Biochar

Chitosan

Sludge disposal

The greenhouse effect has become an urgent environmental issue. Since the Industrial Revolution, the burning of fossil fuels such as coal and oil, along with other human activities, has produced a large amount of greenhouse gases, causing a continuous rise in global temperatures, with CO₂ being the predominant greenhouse gas [1]. According to IPCC forecasts, by the year 2100, the concentration of CO₂ in the air will reach 570 ppm, and the temperature will rise by 1.9°C, while 2°C is considered the upper limit for tolerable climate warming. To control the rise in temperature, various countries have proposed a series of carbon reduction measures in recent years, among which carbon capture and storage technologies are considered the most promising, contributing 14% to carbon reduction [2]. Carbon capture technology is a crucial component, primarily involving absorption, adsorption, and membrane separation techniques. Among these, the adsorption method is widely used and studied due to its simplicity, low corrosiveness to equipment, and low energy requirements [3].

Adsorbents used in adsorption methods include metal adsorbents, mineral adsorbents, and carbon-based adsorbents, especially biochar [4–6]. Due to its widespread availability, low cost, and rich functional groups, biochar is an ideal material for CO₂ adsorption. Currently, the biochar materials used to prepare CO₂ adsorbents primarily include agricultural and forestry wastes such as rattan thorns, wheat straw, and palm leaves, with little research focusing on urban solid wastes like sludge[7–9]. Sludge, the solid material in urban sewage, has become an environmental issue that cannot be ignored on the path to sustainable development due to its large volume, high content of heavy metals, and numerous toxic and hazardous substances [10]. Therefore, this study uses urban residual sludge as a raw material to produce biochar for adsorbing CO₂, exploring ways to utilize sludge as a resource.

However, biochar directly pyrolyzed from residual sludge has a smaller surface area, fewer functional groups, and fewer adsorption sites. Therefore, researchers tend to modify biochar to enhance its CO₂ adsorption capacity [11]. The use of iron oxide and copper oxide to modify sugarcane bagasse biochar has been found to enhance the surface polarity of the adsorbent, which is beneficial for CO₂ adsorption [12]. Studies on biochar loaded with cerium oxide have demonstrated its effective CO₂ adsorption performance [13]. These results indicate that adding reagents can enhance the CO₂ adsorption performance of biochar.

Some chemical reagents, while improving the adsorption performance of CO₂, also bring environmental burdens. For example, metal agents are not only expensive but also cause significant heavy metal pollution, hence there is a preference for choosing green, non-polluting reagents. Chitosan, a non-toxic, biodegradable green material, not only serves as a dehydrating agent reducing the moisture content of sludge cakes, but it has also been found to enhance the physical strength and adsorption properties of activated carbon [14]. Research by Ababneh and Hamee has shown that chitosan can capture CO₂ by forming ammonium carbamate [15]. Therefore, we have chosen sludge as a raw material and used chitosan to condition the sludge to prepare biochar (SBCC), comparing it with raw sludge biochar (RSB) to analyze its CO₂ adsorption mechanism. This study analyzed the surface morphology, specific surface area, surface elements, and functional groups of sludge biochar, and studied the adsorption stability and kinetics of SBCC for CO₂, aiming to obtain an efficient CO₂ adsorption material and provide a viable way for the resource utilization of sludge.

In this study, the physicochemical properties of sludge biochar such as surface morphology, specific surface area, surface elements, and functional groups were analyzed, and the adsorption stability and adsorption kinetics of SBCC on CO₂ was investigated, aiming to obtain an efficient adsorption material for CO₂ adsorption and provide a feasible way for sludge treatment.

2.1 Materials and preparation

2.1.1 Experimental Materials

The study utilizes sludge from the Xintian Town wastewater treatment plant in Wanzhou District, Chongqing, as the research subject. The sludge was filtered, dried, and milled to obtain particles of 80–100 mesh as raw materials. Chitosan was purchased from Cologne Chemicals Co. Ltd., Chengdu.

2.1.2 Preparation of Biochar

Chitosan was added to the sludge at 2.7 mg/gDS (Dry Solid) and mixed thoroughly using a six-spindle stirrer. The mixture was then filtered using a Buchner funnel, dried, and milled through an 80–100 mesh nylon sieve. Biochar was subsequently prepared in a pyrolysis furnace at temperatures of 400°C, 600°C, and 800°C. Initially, the air in the tubes was purged with nitrogen for 10 min, followed by maintaining the desired temperature under a nitrogen atmosphere for 60 min. To minimize carbon emissions during pyrolysis, the furnace was primarily heated using oil.

2.2 Testing the Adsorption Performance of Biochar

Approximately 5 mg of the sample was placed on a thermogravimetric balance. The biochar was degassed at 120°C under an N₂ atmosphere for 40 min, then allowed to naturally cool to specified temperatures (30°C, 50°C, 70°C, 90°C, 110°C), with a gas flow rate of 50 ml/min to complete CO₂ adsorption over 2 hours at atmospheric pressure. Conduct two parallel experiments and analyze the biochar that captures the optimum amount of CO₂ using thermogravimetric analysis.

2.3 Testing Method for the Stability of CO₂ Adsorption by Biochar

The same preprocessing and stabilization conditions used for single-weight adsorption measurements were applied to cyclic stability tests. After adsorption, five adsorption-desorption cycles were conducted. Each cycle consisted of 1 hour of CO₂ adsorption, followed by 1 hour of desorption at 120°C with N₂ purging (90 ml/min).

2.4 Material characterization

The specific surface area and porosity of SBCC were measured using an automated surface area analyzer (McASAP2460, USA). The functional groups on the surface of SBCC were analyzed using Fourier-transform infrared spectroscopy (Shimadzu prestige-21, Japan). The surface morphology and elemental composition of SBCC were examined using a scanning electron microscope (Zeiss Sigma 300, Germany) and X-ray spectroscopy (Zeiss Sigma 300, Germany). The adsorption capacity of SBCC for CO₂ was analyzed using thermogravimetry (Shimadzu 60A, Japan).

2.5 Data Analysis

2.5.1 Absorption capacity of biochar

The adsorption capacity of biochar for CO₂ is calculated by Eq. (1).

$$\:\text{Q}=\frac{{q}_{2}-{q}_{1}}{{q}_{1}}\times\:1000$$

Where $\:\text{Q}$ is the adsorption amount of biochar, mg-g^− 1; $\:{q}_{1}$ is the initial weight of biochar, mg; $\:{q}_{2}$ is the weight of CO₂ adsorbed biochar, mg.

2.5.2 Kinetic analysis

The quasi-primary kinetic model (2), quasi-secondary kinetic model (3), and Intra-particle diffusion model (4) were used to fit the adsorption data.

$$\:{q}_{t}={q}_{e}(1-{e}^{\frac{-{k}_{1}t}{2.303}})$$

$$\:{q}_{t}=\frac{{k}_{2}t{q}_{e}^{2}}{1+{k}_{2}t{q}_{e}}\:$$

$$\:{q}_{t}={k}_{f}{t}^{1/2}+c$$

Where $\:{q}_{t}$ is the CO₂ adsorption content of biochar at time, mg/g; $\:{q}_{e}$ is the amount of CO₂ adsorbed by biochar when adsorption reaches equilibrium, mg/g; $\:\text{t}$ is the time of CO₂ adsorption by biochar; $\:{k}_{1}$ is the quasi primary kinetic constant; $\:{k}_{2}$ is the quasi secondary kinetic constant; $\:{k}_{f}$ is the internal diffusivity constant; $\:\text{c}$ is the boundary layer thickness related constant .

3.1 Effect of pyrolysis temperature on CO₂ adsorption by SBCC

From Fig. 1(a), it is evident that the adsorption capacities of SBCC for CO₂ at pyrolysis temperatures of 400°C, 600°C, and 800°C are respectively 25.94 mg/g, 39.41 mg/g, and 22.90 mg/g. The best adsorption performance by SBCC is at 600°C, hence this is the optimal preparation temperature for SBCC. As shown in Fig. 1(b), the adsorption capacities of RSB prepared at 400°C, 600°C, and 800°C are 17.28 mg/g, 13.82 mg/g, and 21.42 mg/g, respectively, with the highest adsorption at 800°C, thus the optimal preparation temperature for RSB is 800°C. Relative to RSB, SBCC has a lower optimal preparation temperature and enhanced CO₂ adsorption capacity at each preparation temperature. Not only does it enhance adsorption capacity, but it also reduces energy consumption compared to higher temperatures, thus supporting sustainable biochar production processes.

3.2 Effect of adsorption temperature on CO₂ adsorption by SBCC

As shown in Fig. 2, the effect of adsorption temperature on CO₂ adsorption by SBCC and RSB is depicted. From Fig. 2(a), it is observed that as the adsorption temperature increases from 30°C to 110°C, the adsorption capacity of SBCC for CO₂ gradually decreases, with capacities of 89.88 mg/g, 39.41 mg/g, 25.08 mg/g, 28.20 mg/g, and 16.22 mg/g, respectively, with the optimal CO₂ adsorption at 30°C. According to Fig. 2(b), RSB exhibits the highest CO₂ adsorption capacity (28.36 mg/g) at 30°C. This is because SBCC and RSB are porous materials, and adsorption is primarily an exothermic reaction; higher temperatures intensify molecular motion, which is detrimental to adsorption.

3.3 Study on the mechanism of CO₂ adsorption by SBCC

3.3.1 Surface Structure Analysis of SBCC

The surface structures of RSB and SBCC are shown in Fig. 3. As seen in Fig. 3(a), compared to RSB, the surface of SBCC is smoother with some areas showing fibrous structures due to the binding of chitosan to the biochar surface. The BET characterization results under N₂ conditions for SBCC and RSB are shown in Table 1. Table 1 reveals that the surface area and pore volume of SBCC are less than those of RSB, but the pore sizes are larger, which is due to the conditioning of sludge with chitosan. Chitosan has blocked some of the smaller pores in the biochar, leaving larger pore structures, thus reducing some of SBCC's physical adsorption capacity. This is consistent with reports by Zhou et al [16]. However, Fig. 2 indicates that compared to RSB, the adsorption capacity of SBCC has nearly tripled, possibly because chemical adsorption has replaced physical adsorption as the primary mechanism after chitosan conditioning [17]. Table 1 also shows an increase in the carbon and nitrogen content of SBCC, doubling the nitrogen content, which indicates the successful attachment of chitosan to the biochar. Researchers have noted that N atoms have strong dipole-quadrupole interactions with CO₂, and an increase in N content enhances SBCC's adsorption capacity for CO₂ [18].

Table 1

Physicochemical properties of SBCC and RSB
Sample name	Specific surface area (m²/g)	Pore volume (cm³/g)	Average hole (nm)	C	N	O
SBCC	24.08	0.066	10.94	54.09	2.39	33.39
RSB	51.92	0.11	8.24	52.22	1.04	34.81

3.3.2 Functional group analysis of SBCC

The infrared functional group spectrum of SBCC is shown in Fig. 4. SBCC exhibits four peaks: at 492 cm^− 1 representing aromatic C-H, indicating strong aromaticity; at 1016 cm^− 1 representing the C-OH (C-O stretching) of alcohols; at 1637 cm^− 1 showing the C = O stretching vibration of carboxylic groups; and a distinct N-H stretching peak at 3458 cm-1 [9, 19, 20]. Compared to RSB, SBCC has increased carboxylic and amino groups, as the amide groups in chitosan partially hydrolyze to carboxylic groups under the alkaline conditions present in sludge (pH > 6) [21]. However, the peak at 774 cm^− 1 disappeared due to chitosan covering most of the biochar surface, obscuring the original functional groups. The presence of amino groups indicates successful attachment of chitosan to the biochar. Evidence suggests that oxygen-containing acidic functional groups like carboxylic groups can enhance CO₂ adsorption on carbon surfaces by promoting hydrogen bonding between CO₂ molecules and the carbon surface. Alkaline functional groups may also react with CO₂, improving the adsorption capacity [22].

3.3.3 Adsorption kinetics analysis of SBCC

The adsorption behavior of RSB and SBCC for CO₂ was modeled using the quasi-first-order kinetic model, the quasi-second-order kinetic model, and the intra-particle diffusion model. Detailed data are presented in Table 2, and the fit plots are shown in Fig. 5. The equilibrium adsorption capacity of RSB, calculated using the quasi-first-order kinetic model, was 28.84 mg/g, closely matching the actual value with a correlation coefficient above 0.9, indicating that this model is suitable for CO₂ adsorption by RSB. In the quasi-first-order kinetic model, the calculated results for SBCC differed significantly from the actual values; despite a correlation coefficient above 0.9, this model is not applicable to SBCC. The fitting results of the quasi-second-order kinetic model showed that the calculated equilibrium adsorption capacities of RSB and SBCC were close to the measured values. However, the correlation coefficient for RSB was very low, rendering the model unsuitable. For SBCC, the correlation coefficient exceeded 0.99, making the quasi-second-order kinetic model applicable to its CO₂ adsorption analysis. This indicates that the adsorption process is influenced by chemical adsorption, confirming the hypothesis in Table 2 that the addition of chitosan covers the surface of RSB, enhancing the chemical adsorption capacity of SBCC for CO₂. The intra-particle diffusion model solely illustrates the diffusion process of CO₂ within the particles, which may also be influenced by pore diffusion and film diffusion [23]. The fitting data for RSB indicated that k₁ < k₂, suggesting that the adsorption process is a monolayer adsorption on the surface [24].

The adsorption kinetics curve of SBCC as shown in Fig. 5(d) indicates that the adsorption quantity of RSB for CO₂ initially increases rapidly and then stabilizes over time. The adsorption rate of SBCC starts with a steep rise and gradually stabilizes, showing a significant increase compared to RSB. Figure 1 shows that the surface pore distribution of RSB is uniform, with little variation in pore size at the adsorption landing points until all adsorption sites are occupied. In contrast, after modification with chitosan, SBCC develops an uneven distribution of pores, enhancing its adsorption rate.

Table 2

Kinetic analysis of SBCC for CO₂ adsorption.
Sample name		Quasi-first-order kinetic model			Quasi-second-order kinetic model			Intra-particle diffusion model
	q_e,exp(mg/g)	q_e,cal (mg/g)	k₁	r²	q_e,cal (mg/g)	k₁	r²	k₁	c	k₂	c
RSB	28.36	28.84	0.00040	0.9370	31.25	0.001	0.7165	0.14	0.047	0.48	-9.35
SBCC	87.89	0.14	0.00035	0.9582	90.91	0.0001	0.9987	13.74	-31.30	0.17	74.14

3.4 Regeneration Performance Analysis of SBCC

The reusability of an adsorbent is an important criterion for its practical application. This study tested the cyclic adsorption performance of SBCC through five adsorption-desorption experiments [25]. As shown in Fig. 6, the adsorption capacity of SBCC for CO₂ decreases with the number of cycles, due to the active sites on SBCC's surface becoming occupied. However, after five cycles, the adsorption capacity still reaches about 75% of its initial value, demonstrating good reusability.

(1) The preparation and adsorption temperatures are crucial for the CO₂ adsorption effectiveness of RSB and SBCC. This study shows that the optimal preparation temperature for RSB is 800°C, with the best adsorption temperature at 30°C. For SBCC, the optimal preparation temperature is 600°C, also with the best adsorption temperature at 30°C.

(2) Compared to RSB, the chitosan-modified SBCC has reduced surface area and porosity, which decreases its physical adsorption capacity. The hydrolysis of chitosan in sludge generates carboxylic groups, which are beneficial for CO₂ adsorption, and also increases the presence of nitrogen, carboxylic, and N-H groups that facilitate CO₂ adsorption.

(3) Fitting kinetic models revealed that RSB is suitable for the quasi-first-order kinetic model, while SBCC fits the quasi-second-order kinetic model. Chemical adsorption has replaced part of the physical adsorption, enhancing the CO₂ adsorption capacity of the sludge biochar.

CRediT authorship contribution statement

Yue Yu: Methodology, Writing-review & editing. Tongqing Li: Investigation, Methodology. Jiacheng Gui: Software, Methodology. Ming Chen: Validation, Investigation. Qiushi Zheng: Validation, Investigation. Yang Liao: Software, Visualization. Yueyue Yang: Software, Visualization. Yan Wu: Conceptualization, Supervision, Writing original draft, Writing-review & editing, Funding acquisition. Chang Liu: Supervision, Writing-review & editing.

Declaration of Competing Interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Author Contribution

Acknowledgement

This work was supported by the National Natural Science Foundation of China [grant numbers 51808089]; the Graduate Innovation and Entrepreneurship Training Program [grant numbers CYS240756].

T. Tiwari, G.A. Kaur, P.K. Singh, S. Balayan, A. Mishra, A. Tiwari, Emerging bio-capture strategies for greenhouse gas reduction: Navigating challenges towards carbon neutrality, Sci Total Environ, 929 (2024) 172433, https://doi.org/10.1016/j.scitotenv.2024.172433.
D. Baskaran, P. Saravanan, L. Nagarajan, H.-S. Byun, An overview of technologies for capturing, storing, and utilizing carbon dioxide: Technology readiness, large-scale demonstration, and cost, Chemical Engineering Journal, 491 (2024), https://doi.org/10.1016/j.cej.2024.151998.
D.A. Salas, A.J. Boero, A.D. Ramirez, Life cycle assessment of bioenergy with carbon capture and storage: A review, Renewable and Sustainable Energy Reviews, 199 (2024), https://doi.org/10.1016/j.rser.2024.114458.
T.H. Nguyen, H. Gong, S.S. Lee, T.H. Bae, Amine-Appended Hierarchical Ca-A Zeolite for Enhancing CO₂ /CH₄ Selectivity of Mixed-Matrix Membranes, Chemphyschem, 17 (2016) 3165–3169, https://doi.org/10.1002/cphc.201600561.
K.T. Chue., J.N. Kim., Y.J. Yoo., S.H. Cho., Comparison of Activated Carbon and Zeolite 13X for CO₂ Recovery from Flue Gas by Pressure Swing Adsorption, Ind. Eng. Chem. Res., 34 (1995) 591–598,
K. Zhang, Z. Qiao, J. Jiang, Molecular Design of Zirconium Tetrazolate Metal–Organic Frameworks for CO₂ Capture, Crystal Growth & Design, 17 (2016) 543–549, https://doi.org/10.1021/acs.cgd.6b01405.
J.J. Manyà, B. González, M. Azuara, G. Arner, Ultra-microporous adsorbents prepared from vine shoots-derived biochar with high CO2 uptake and CO2/N2 selectivity, Chemical Engineering Journal, 345 (2018) 631–639, https://doi.org/10.1016/j.cej.2018.01.092.
X. Xu, Z. Xu, B. Gao, L. Zhao, Y. Zheng, J. Huang, D.C.W. Tsang, Y.S. Ok, X. Cao, New insights into CO2 sorption on biochar/Fe oxyhydroxide composites: Kinetics, mechanisms, and in situ characterization, Chemical Engineering Journal, 384 (2020), https://doi.org/10.1016/j.cej.2019.123289.
I. Ben Salem, M. El Gamal, M. Sharma, S. Hameedi, F.M. Howari, Utilization of the UAE date palm leaf biochar in carbon dioxide capture and sequestration processes, Journal of Environmental Management, 299 (2021), https://doi.org/10.1016/j.jenvman.2021.113644.
N. Gao, K. Kamran, C. Quan, P.T. Williams, Thermochemical conversion of sewage sludge: A critical review, Progress in Energy and Combustion Science, 79 (2020), https://doi.org/10.1016/j.pecs.2020.100843.
A. Shakya, M. Vithanage, T. Agarwal, Influence of pyrolysis temperature on biochar properties and Cr(VI) adsorption from water with groundnut shell biochars: Mechanistic approach, Environmental Research, 215 (2022), https://doi.org/10.1016/j.envres.2022.114243.
F. Raganati, F. Miccio, P. Ammendola, Adsorption of Carbon Dioxide for Post-combustion Capture: A Review, Energy & Fuels, 35 (2021) 12845–12868, https://doi.org/10.1021/acs.energyfuels.1c01618.
S. Shahkarami, R. Azargohar, A.K. Dalai, J. Soltan, Breakthrough CO 2 adsorption in bio-based activated carbons, Journal of Environmental Sciences, 34 (2015) 68–76, https://doi.org/10.1016/j.jes.2015.03.008.
I.O. Saheed, W.D. Oh, F.B.M. Suah, Chitosan modifications for adsorption of pollutants – A review, Journal of Hazardous Materials, 408 (2021), https://doi.org/10.1016/j.jhazmat.2020.124889.
H. Ababneh, B.H. Hameed, Chitosan-derived hydrothermally carbonized materials and its applications: A review of recent literature, International Journal of Biological Macromolecules, 186 (2021) 314–327, https://doi.org/10.1016/j.ijbiomac.2021.06.161.
Y. Zhou, B. Gao, A.R. Zimmerman, H. Chen, M. Zhang, X. Cao, Biochar-supported zerovalent iron for removal of various contaminants from aqueous solutions, Bioresour Technol, 152 (2014) 538–542, https://doi.org/10.1016/j.biortech.2013.11.021.
C. Liu, C. Fu, T. Li, P. Zhang, Y. Xia, Y. Wu, Q. Lan, Y. Li, Y. Zhang, J. Gui, CO2 capture using biochar derived from conditioned sludge via pyrolysis, Separation and Purification Technology, 314 (2023), https://doi.org/10.1016/j.seppur.2023.123624.
A. Alabadi, S. Razzaque, Y. Yang, S. Chen, B. Tan, Highly porous activated carbon materials from carbonized biomass with high CO2 capturing capacity, Chemical Engineering Journal, 281 (2015) 606–612, https://doi.org/10.1016/j.cej.2015.06.032.
A. Raj, A. Yadav, S. Arya, R. Sirohi, S. Kumar, A.P. Rawat, R.S. Thakur, D.K. Patel, L. Bahadur, A. Pandey, Preparation, characterization and agri applications of biochar produced by pyrolysis of sewage sludge at different temperatures, Science of The Total Environment, 795 (2021), https://doi.org/10.1016/j.scitotenv.2021.148722.
L. Kong, J. Liu, Q. Zhou, Z. Sun, Z. Ma, Sewage sludge derived biochars provoke negative effects on wheat growth related to the PTEs, Biochemical Engineering Journal, 152 (2019), https://doi.org/10.1016/j.bej.2019.107386.
A. Ashraf, J. Dutta, A. Farooq, M. Rafatullah, K. Pal, G.Z. Kyzas, Chitosan-based materials for heavy metal adsorption: Recent advancements, challenges and limitations, Journal of Molecular Structure, 1309 (2024), https://doi.org/10.1016/j.molstruc.2024.138225.
P.D. Dissanayake, S. You, A.D. Igalavithana, Y. Xia, A. Bhatnagar, S. Gupta, H.W. Kua, S. Kim, J.-H. Kwon, D.C.W. Tsang, Y.S. Ok, Biochar-based adsorbents for carbon dioxide capture: A critical review, Renewable and Sustainable Energy Reviews, 119 (2020), https://doi.org/10.1016/j.rser.2019.109582.
J.-Y. Li, D.K. Wang, H.-H. Tseng, M.-Y. Wey, Solvent effects on diffusion channel construction of organosilica membrane with excellent CO2 separation properties, Journal of Membrane Science, 618 (2021), https://doi.org/10.1016/j.memsci.2020.118758.
C. Yang, J. Liu, S. Lu, Pyrolysis temperature affects pore characteristics of rice straw and canola stalk biochars and biochar-amended soils, Geoderma, 397 (2021), https://doi.org/10.1016/j.geoderma.2021.115097.
J. Han, L. Zhang, B. Zhao, L. Qin, Y. Wang, F. Xing, The N-doped activated carbon derived from sugarcane bagasse for CO2 adsorption, Industrial Crops and Products, 128 (2019) 290–297, https://doi.org/10.1016/j.indcrop.2018.11.028.

No competing interests reported.

floatimage1.png

Download PDF

Version 1

posted

You are reading this latest preprint version

CO2 capture using biochar derived from municipal residual sludge conditioned with chitosan

Status:

Version 1

Abstract

Figures

1. Introduction

2. Materials and Methods

2.1 Materials and preparation

2.1.1 Experimental Materials

2.1.2 Preparation of Biochar

2.2 Testing the Adsorption Performance of Biochar

2.3 Testing Method for the Stability of CO₂ Adsorption by Biochar

2.4 Material characterization

2.5 Data Analysis

2.5.1 Absorption capacity of biochar

2.5.2 Kinetic analysis

3. Results and Discussion

3.1 Effect of pyrolysis temperature on CO₂ adsorption by SBCC

3.2 Effect of adsorption temperature on CO₂ adsorption by SBCC

3.3 Study on the mechanism of CO₂ adsorption by SBCC

3.3.1 Surface Structure Analysis of SBCC

3.3.2 Functional group analysis of SBCC

3.3.3 Adsorption kinetics analysis of SBCC

3.4 Regeneration Performance Analysis of SBCC

4. Conclusion

Declarations

Declaration of Competing Interest

Author Contribution

Acknowledgement

References

Additional Declarations

Supplementary Files

Status:

Version 1

CO2 capture using biochar derived from municipal residual sludge conditioned with chitosan

Status:

Version 1

Abstract

Figures

1. Introduction

2. Materials and Methods

2.1 Materials and preparation

2.1.1 Experimental Materials

2.1.2 Preparation of Biochar

2.2 Testing the Adsorption Performance of Biochar

2.3 Testing Method for the Stability of CO2 Adsorption by Biochar

2.4 Material characterization

2.5 Data Analysis

2.5.1 Absorption capacity of biochar

2.5.2 Kinetic analysis

3. Results and Discussion

3.1 Effect of pyrolysis temperature on CO2 adsorption by SBCC

3.2 Effect of adsorption temperature on CO2 adsorption by SBCC

3.3 Study on the mechanism of CO2 adsorption by SBCC

3.3.1 Surface Structure Analysis of SBCC

3.3.2 Functional group analysis of SBCC

3.3.3 Adsorption kinetics analysis of SBCC

3.4 Regeneration Performance Analysis of SBCC

4. Conclusion

Declarations

Declaration of Competing Interest

Author Contribution

Acknowledgement

References

Additional Declarations

Supplementary Files

Status:

Version 1

2.3 Testing Method for the Stability of CO₂ Adsorption by Biochar

3.1 Effect of pyrolysis temperature on CO₂ adsorption by SBCC

3.2 Effect of adsorption temperature on CO₂ adsorption by SBCC

3.3 Study on the mechanism of CO₂ adsorption by SBCC