Response Surface Optimization, Isotherm, Kinetic and Thermodynamic Studies of Methylene Blue Adsorption onto Conductive Poly(3-butylthiophene)
DOI:
https://doi.org/10.56919/usci.2651.046Keywords:
Poly(3-butylthiophene), Methylene blue, Adsorption, Response Surface Methodology, wastewater remediationAbstract
Conductive poly(3-butylthiophene) (P3BT) was synthesized via oxidative polymerization and investigated as an adsorbent for methylene blue (MB) removal from aqueous solutions. Structural characterization using FTIR, SEM, XRD, and BET analyses confirmed the formation of a porous semi-crystalline polymer with a BET surface area of 392.5 m² g⁻¹ and abundant adsorption-active sites. Adsorption parameters, including pH, adsorbent dosage, initial dye concentration, contact time, and temperature, were optimized using Response Surface Methodology (RSM) based on Box–Behnken Design. The developed quadratic model was statistically significant (p < 0.0001) with excellent predictive capability (R² = 0.9987), and the adjusted R² and predicted R² were in agreement, with no significant lack of fit. Under optimized conditions of pH 7.5, 0.55 g L⁻¹ adsorbent dosage, 105 mg L⁻¹ dye concentration, 70 min contact time, and 40 °C, a maximum adsorption capacity of 270.46 mg g⁻¹ and 99.6% methylene blue removal efficiency were achieved. Adsorption equilibrium followed the Langmuir isotherm model (R² = 0.9939), indicating monolayer adsorption on homogeneous active sites, while adsorption kinetics followed the pseudo-second-order model (R² = 0.9978), suggesting adsorption was governed predominantly by surface interaction processes. Thermodynamic studies revealed spontaneous, endothermic adsorption, characterized by a negative Gibbs free energy (ΔG° < 0) and a positive enthalpy change (ΔH° = 60.01 kJ mol⁻¹). Regeneration studies showed that P3BT retained approximately 59% adsorption efficiency after five adsorption–desorption cycles, demonstrating moderate reusability and structural stability. The findings establish that conductive P3BT is a promising high-capacity adsorbent for the remediation of dye-contaminated wastewater.
References
Ahmad, R., & Ansari, K. J. P. B. (2021). Comparative study for adsorption of congo red and methylene blue dye on chitosan modified hybrid nanocomposite. 108, 90-102. DOI: https://doi.org/10.1016/j.procbio.2021.05.013
Birniwa, A. H., Mahmud, H. N. M. E., Abdullahi, S. S. a., Habibu, S., Jagaba, A. H., Ibrahim, M. N. M., … Umar, K. J. P. (2022). Adsorption behavior of methylene blue cationic dye in aqueous solution using polypyrrole-polyethylenimine nano-adsorbent. 14(16), 3362. DOI: https://doi.org/10.3390/polym14163362
El Jery, A., Alawamleh, H. S. K., Sami, M. H., Abbas, H. A., Sammen, S. S., Ahsan, A., … Osman, H. J. S. R. (2024). Isotherms, kinetics and thermodynamic mechanism of methylene blue dye adsorption on synthesized activated carbon. 14(1), 970. DOI: https://doi.org/10.1038/s41598-023-50937-0
Goswami, M. K., Srivastava, A., Dohare, R. K., Tiwari, A. K., & Srivastav, A. J. E. S. (2023). Recent advances in conducting polymer-based magnetic nanosorbents for dyes and heavy metal removal: fabrication, applications, and perspective. 30(29), 73031-73060. DOI: https://doi.org/10.1007/s11356-023-27458-4
Habibu, S., Ladan, M., Safana, A. A., Dandalma, Z. A., Saleh, I., & Abdullahi, S. R. J. U. S. (2023). Optimization of methylene blue adsorption onto activated carbon derived from pineapple peel waste using response surface methodology. 2(4), 45-55. DOI: https://doi.org/10.56919/usci.2324.006
Husain, A., Ahmad, S., & Mohammad, F. J. J. E. S. C. I. (2020). Preparation and applications of polythiophene nanocomposites. 36-53.
Igwegbe, C. A., Mohmmadi, L., Ahmadi, S., Rahdar, A., Khadkhodaiy, D., Dehghani, R., & Rahdar, S. J. M. (2019). Modeling of adsorption of methylene blue dye on Ho-CaWO4 nanoparticles using response surface methodology (RSM) and artificial neural network (ANN) techniques. 6, 1779-1797. DOI: https://doi.org/10.1016/j.mex.2019.07.016
Imam, S. S., & Hamza, M. F. J. E. T. R. (2025). Adsorptive removal of neutral red dye from aquatic environments: a review of adsorbent materials, kinetics, isotherms, thermodynamics and future prospects. 14(1), 69-93. DOI: https://doi.org/10.1080/21622515.2025.2458090
Kocijan, M., Ćurković, L., Vengust, D., Radošević, T., Shvalya, V., Gonçalves, G., & Podlogar, M. J. M. (2023). Synergistic remediation of organic dye by titanium dioxide/reduced graphene oxide nanocomposite. 28(21), 7326. DOI: https://doi.org/10.3390/molecules28217326
Ladan, M., Salisu, A., & Habibu, S. (2025). Efficient dye removal using cellulose-TiO2 nanocomposites synthesized from millet husk.
Ladan, M., Salisu, A., & Habibu, S. J. C. J. (2024). Efficient dye removal using cellulose-TiO2 nanocomposites synthesized from millet husk. 15(2), 54-66.
Liu, Q., Li, Y., Chen, H., Lu, J., Yu, G., Möslang, M., & Zhou, Y. J. J. o. H. M. (2020). Superior adsorption capacity of functionalised straw adsorbent for dyes and heavy-metal ions. 382, 121040. DOI: https://doi.org/10.1016/j.jhazmat.2019.121040
Mobin, M., & Ansar, F. J. A. o. (2022). Polythiophene (PTh)-TiO2-reduced graphene oxide (rGO) nanocomposite coating: synthesis, characterization, and corrosion protection performance on low-carbon steel in 3.5 wt% NaCl solution. 7(50), 46717-46730. DOI: https://doi.org/10.1021/acsomega.2c05678
Muhammad, A. A., & Abdulmumini, H. J. C. R. (2022). Raw water lily (nymphaea lotus) leaves powder as an effective adsorbent for the adsorption of malachite green dye from aqueous solution. 5(4), 250-260.
Rabi'u, M. A., Hussaini, M., Usman, B., & Ibrahim, M. B. J. B. J. o. P. (2023). Adsorption of basic magenta dye from aqueous solution using raw and acid modified yam peel as adsorbent. 14(1), 460-466.
Satyam, S., & Patra, S. J. H. (2024). Innovations and challenges in adsorption-based wastewater remediation: A comprehensive review. 10(9). DOI: https://doi.org/10.1016/j.heliyon.2024.e29573
Shajahan, A., Shankar, S., Sathiyaseelan, A., Narayan, K. S., Narayanan, V., Kaviyarasan, V., & Ignacimuthu, S. J. I. J. o. B. M. (2017). Comparative studies of chitosan and its nanoparticles for the adsorption efficiency of various dyes. 104, 1449-1458. DOI: https://doi.org/10.1016/j.ijbiomac.2017.05.128
Sulaiman, M. S., Ajayi, O. A., & Olakunle, M. S. J. I. C. C. (2024). Optimization of cadmium adsorption on metal organic frameworks MIL-53 (Fe) using response surface methodology. 159, 111765. DOI: https://doi.org/10.1016/j.inoche.2023.111765
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