Comparison of Moisture Sorption Isotherm Models and Desorption Kinetics of Silica-Impregnated Biochar Composite Desiccant

Abstract

This study investigates the moisture sorption behavior and regeneration performance of a composite based on biomass-derived activated carbon (biochar) impregnated with silica (Na2SiO3) named AC/Si as desiccant. The composite was characterized by SEM and nitrogen adsorption analysis to evaluate structural changes after impregnation. Water vapor adsorption isotherms were fitted to five models (BET, Halsey, Henderson, Oswin, and Smith), with the Halsey model exhibiting the highest accuracy. Desorption kinetics were evaluated at 313–333 K using pseudo-first-order (PFO) and pseudo-second-order (PSO) models, with the PSO model providing a superior fit as evidenced by high R2 and low RMSE. The Arrhenius equation was employed to determine the activation energy (Ea) of the composite's desorption process, resulting in an Ea of 40.23 kJ/mol, which suggests efficient regeneration under moderate heating. These findings support the potential of AC/Si composites as energy-efficient, reusable desiccants for general-purpose moisture control.

Keywords

• Biochar
• Composite Desiccant
• Water Vapor Adsorption
• Moisture Sorption Isotherm
• Desorption Kinetic

References

1. [1] Channoy C, Maneewan S, Chirarattananon S, Punlek C. Development and Characterization of Composite Desiccant Impregnated with LiCl for Thermoelectric Dehumidifier (TED). Energies. 2022;15(5). doi : 10.3390/en15051778
2. [2] Liu H, Sundarrajan S, Kumar GV, Ramakrishna S. Review on Polymer Materials for Solid Desiccant Cooling System. Macromol Mater Eng. 2023;308(12). doi: 10.1002/mame.202300176
3. [3] Agassin STR, Dognini J, Paulino AT. Raw Rice Husk Biochar as a Potential Valuable Industrial Byproduct for the Removal of Rhodamine B from Water. Water. 2023;15(21). doi: 10.3390/w15213849
4. [4] A’yuni DQ, Hadiantono H, Velny V, Subagio A, Djaeni M, Mufti N. Effect of Potassium Hydroxide Concentration and Activation Time on Rice Husk-Activated Carbon for Water Vapor Adsorption. Iran J Mater Sci Eng. 2024;21(3):1–10. doi: 10.22068/ijmse.3522
5. [5] Drużyński S, Mazurek K, Kiełkowska U, Wróbel-Kaszanek A, Igliński B. Physicochemical Properties and Application of Silica-Doped Biochar Composites as Efficient Sorbents of Copper from Tap Water. Materials (Basel). 2023;16(7). doi: 10.3390/ma16072794
6. [6] Guo Y, Wang Q. Exploring the adsorption potential of Na2SiO3-activated porous carbon materials from waste bamboo biomass for ciprofloxacin rapid removal in wastewater. Environ Technol Innov. 2023;32. doi: 10.3390/ma16072794
7. [7] Mittal H, Alili A Al, Alhassan SM. Capturing Water Vapors From Atmospheric Air Using Superporous Gels. Sci Rep. 2022;12(1). doi : 10.1038/s41598-022-08191-3
8. [8] Zhu Z, Zhang M. Water Vapor Adsorption on Desiccant Materials for Rotary Desiccant Air Conditioning Systems. Processes. 2023;11(7):2166. doi : 10.3390/pr11072166

9. [9] Balashov E, Mukhina I, Rizhiya E. Differences in Water Vapor Adsorption-Desorption of Non Aged and 3-Year Aged Biochar in Sandy Spodosols. Acta Hortic Regiotect. 2019;22(2):56–60. doi : 10.2478/ahr-2019-0010
10. [10] Kubota M, Nakai R, Yamashita S, Kita H, Tokuyama H. Water Vapor Adsorption Behavior of Thermosensitive Polymers for Desiccant Humidity Control Systems. Isij Int. 2022;62(12):2536–41. doi: 10.2355/isijinternational.isijint-2022-204
11. [11] A’yuni DQ, Subagio A, Hadiyanto H, Kumoro AC, Djaeni M. Microstructure silica leached by NaOH from semi-burned rice husk ash for moisture adsorbent. Arch Mater Sci Eng. 2021;108(1):5–15. doi : 10.5604/01.3001.0015.0248
12. [12] Majd MM, Kordzadeh-Kermani V, Ghalandari V, Askari A, Sillanpää M. Adsorption isotherm models: A comprehensive and systematic review (2010−2020). Sci Total Environ. 2022;812. doi : 10.1016/j.scitotenv.2021.151334
13. [13] Jia R-Q, Liang S, Xue Z-Y, Chu G-W, Zhang L-L, Chen J-F. Reaction kinetic modeling of carbon dioxide desorption in aqueous amine solutions. Sep Purif Technol. 2025;359:130578. doi : 10.1016/j.seppur.2024.130578
14. [14] Le TP, Luong HVT, Nguyen HN, Pham TKT, Trinh Le TL, Tran TBQ, et al. Insight into adsorption-desorption of methylene blue in water using zeolite NaY: Kinetic, isotherm and thermodynamic approaches. Results in Surfaces and Interfaces.2024;16:100281. doi: 10.1016/j.rsurfi.2024.100281
15. [15] Cortés J-C, Navarro-Quiles A, Santonja F-J, Sferle S-M. Statistical analysis of randomized pseudo-first/second order kinetic models. Application to study the adsorption on cadmium ions onto tree fern. Chemom Intell Lab Syst. 2023;240:104910. doi : 10.1016/j.chemolab.2023.104910
16. [16] Gao L, Goldfarb JL. Heterogeneous Biochars From Agriculture Residues and Coal Fly Ash for the Removal of Heavy Metals From Coking Wastewater. RSC Adv. 2019;9(28):16018–27. doi : 10.1039/c9ra02459j
17. [17] Lim MS, Kang SH, Song D yeon, Chae JS, Lee JW, Lee Y, et al. Tailoring mesoporous and macroporous structures in activated carbon from NaOH-pretreated oak for superior supercapacitors. J Energy Storage. 2024;96(June). doi : 10.1016/j.est.2024.112729
18. [18] Wang C, Yang B, Ji X, Zhang R, Wu H. Study on activated carbon/silica gel/lithium chloride composite desiccant for solid dehumidification. Energy. 2022;251. doi: 10.1016/j.energy.2022.123874
19. [19] Viisanen Y, Lbadaoui-Darvas M, Piedehierro AA, Welti A, Nenes A, Laaksonen A. Water Vapor Adsorption–Desorption Hysteresis Due to Clustering of Water on Nonporous Surfaces. Langmuir. 2024. doi : 10.1021/acs.langmuir.4c02950
20. [20] Gonzalez-Hourcade M, Reis GS dos, Grimm A, Dinh VM, Lima EC, Larsson SH, et al. Microalgae biomass as a sustainable precursor to produce nitrogen-doped biochar for efficient removal of emerging pollutants from aqueous media Microalgae biomass as a sustainable precursor to produce nitrogen-doped biochar for efficient removal of emergi. J Clean Prod. 2022;348. doi : 10.1016/j.jclepro.2022.131280
21. [21] Alprol AE, Heneash AMM, Ashour M, Abualnaja KM, Alhashmialameer D, Mansour AT, et al. Potential Applications of Arthrospira platensis Lipid-Free Biomass in Bioremediation of Organic Dye from Industrial Textile Effluents and Its Influence on Marine Rotifer (Brachionus plicatilis). Materials (Basel). 2021;14(16):4446. doi: 10.3390/ma14164446
22. [22] Dada AO, Adekola FA, Odebunmi EO, Ogunlaja AS, Bello OS. Two–three parameters isotherm modeling, kinetics with statistical validity, desorption and thermodynamic studies of adsorption of Cu(II) ions onto zerovalent iron nanoparticles. Sci Rep. 2021;11(1):1–15. doi : 10.1038/s41598-021-95090-8
23. [23] Sharma K, Sadhanala HK, Mastai Y, Porat Z, Gedanken A. Sonochemically Prepared BSA Microspheres as Adsorbents for the Removal of Organic Pollutants from Water. Langmuir. 2021;37(32):9927–38. doi: 10.1021/acs.langmuir.1c01716
24. [24] Sun S, Yu Q, Li M, Hong Z, Wang Y, Zhang Y. Surface Modification of Porous Carbon Nanomaterials for Water Vapor Adsorption. Acs Appl Nano Mater. 2023;6(4):2822–34. doi : 10.1021/acsanm.2c05205
25. [25] Huang Z, Zhang T, Ju A, Xu Z, Zhao Y. Macroporous, Highly Hygroscopic, and Leakage-Free Composites for Efficient Atmospheric Water Harvesting. ACS Appl Mater Interfaces. 2024;16(13):16893–902. doi: 10.1021/acsami.4c01888
26. [26] Zheng X, Ma Q, Wan T, Wang W, Pan Q, Wang RZ. Rape Pollen‐Based Composite Sorbent With Thermo‐Responsive and Photothermal Properties for Atmospheric Water Harvesting. Adv Funct Mater. 2024;34(46). doi: 10.1002/adfm.202407127
27. [27] Simić M, Petrović J, Šoštarić T, Ercegović M, Milojković J, Lopičić Z, et al. A Mechanism Assessment and Differences of Cadmium Adsorption on Raw and Alkali-Modified Agricultural Waste. Processes. 2022;10(10):1957. doi: 10.3390/pr10101957
28. [28] Riaz N, Sultan M, Miyazaki T, Shahzad MW, Farooq M, Sajjad U, et al. A review of recent advances in adsorption desalination technologies. Int Commun Heat Mass Transf. 2021;128:105594.doi:10.1016/j.icheatmasstransfer.2021.105594
29. [29] Ramlogan M V, Rabinovich A, Rouff AA. Thermochemical Analysis of Ammonia Gas Sorption by Struvite from Livestock Wastes and Comparison with Biochar and Metal–Organic Framework Sorbents. Environ Sci Technol. 2020 Oct 20;54(20):13264–73. doi : 10.1021/acs.est.0c02572
30. [30] Márquez A, Erramuspe IBV, Via BK, Sastri B, Banerjee S. Regeneration of Spent Desiccants With Supercritical CO2. Ind Eng Chem Res. 2024;63(49):21154–7. doi: 10.1021/acs.iecr.4c03636
31. [31] Ju A, Xu Z, Huang Z, Zhang T, Zhao Y. Metal‐ and Halide‐Free, Macroporous Hygroscopic Polymers for Efficient Atmospheric Water Harvesting. Macromol Rapid Commun. 2024;46(4). doi: 10.1002/marc.202400811