Synthesis and characterization of copper nanoparticle-based hydrogel and its applications in catalytic reduction and adsorption of basic blue 3

Sultan Alam; Imran Badshah; Shahid Khan; Luqman Ali Shah; Muhammad Zahoor; Muhammad Naveed Umar; Riaz Ullah; Essam A Ali

doi:10.1016/j.heliyon.2024.e25836

Synthesis and characterization of copper nanoparticle-based hydrogel and its applications in catalytic reduction and adsorption of basic blue 3

Heliyon. 2024 Feb 9;10(4):e25836. doi: 10.1016/j.heliyon.2024.e25836. eCollection 2024 Feb 29.

Authors

Sultan Alam¹, Imran Badshah¹, Shahid Khan¹, Luqman Ali Shah², Muhammad Zahoor³, Muhammad Naveed Umar⁴, Riaz Ullah⁵, Essam A Ali⁶

Affiliations

¹ Department of Chemistry, University of Malakand, Chakdara Dir Lower, 18800, Pakistan.
² National Center of Excellence in Physical Chemistry (NCE), University of Peshawar, Pakistan.
³ Department of Biochemistry, University of Malakand, Chakdara Dir Lower, KPK, 18800, Pakistan.
⁴ Department of Chemistry, University of Liverpool, UK.
⁵ Department of Pharmacognosy, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia.
⁶ Department of Pharmaceutical Chemistry, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia.

Abstract

Most of the dyes used in various industries are non-biodegradable and carcinogenic in nature. Therefore, elimination of dyes from textile wastes is mandatory to safeguard the life of human, aquatic animals and aquatic plants. In this connection an effective and eco-friendly hydrogel was synthesized from acrylamide, cellulose, clay, and copper salt abbreviated as AMPS(PHE-Ce)/MC-Cu. The fabricated hydrogel was used as sorbent and catalyst for the adsorption and catalytic reduction of basic blue 3. SEM analysis showed granular texture with small holes or cracks which is basic criteria for an adsorbent surface. The results showed that the BET surface area and the Langmuir surface area were, respectively, 27.87 and 40.32 m²/g. The FTIR analysis confirmed the synthesis of hydrogel, as is evident from peaks at 3500, 3439, 2996, 2414, and 1650 cm^-1, which indicated the presence of OH or NH, -C-O-C-, CH_3, (C[bond, double bond]O), C-N bonds correspondingly. Thermal stability was confirmed by TGA analysis where weight loss in three stages has been observed. The presence of copper was confirmed through EDX (5.02%) indicating the incorporation of cupper nanoparticles in hydrogel surface. The high adsorption capability of 1590 mg/g as recorded for basic blue-3 dye indicates it to be an efficient adsorbent. The swelling behavior characterized by Fickian diffusion up to 7898% clearly indicated significant swelling. Pseudo 2nd-order kinetics and the Langmuir isotherm models were more fit in unfolding kinetics and isothermal data indicating chemisorption with monolayer sorption as evident from the high R² values (0.999) of each model. Thermodynamics considerations indicated that the adsorption process is endothermic with a positive enthalpy value of 1371.32 Jmol^-1. The positive entropy value of 19.70 J/mol.K signifies a higher degree of disorder at the solid-liquid interface. The findings provided a valuable insights into the hydrogel's capacity to adsorb cationic dyes and reduce them catalytically, pointing towards its potential applications in addressing environmental challenges.

Keywords: Adsorption; Copper; Hydrogel; Isotherms; Kinetics.