Design of XGX-g-PAAHs@CuO nanocomposite for efficient removal of methylene blue from water

• Published in: Separation science and technology Vol. 60; no. 11; pp. 1350 - 1369
• Main Authors: Kashaudhan, Kopal, Pande, Poorn Prakash, Sharma, Jyoti, Shankar, Ravi, Nath, Amar, Chaurasiya, Arbind, Singh, Divya, Chaudhary, Aradhana
• Format: Journal Article
• Language: English
• Published: Taylor & Francis 24.07.2025
• Subjects: CuO nanoparticles; MB dye; wastewater treatment; Xanthan gum; XGX-g-PAAHs@CuO nanocomposite
• ISSN: 0149-6395; 1520-5754
• DOI: 10.1080/01496395.2025.2493281

Xanthan gum Xanthate-graft-poly(acrylic acid)@Copper Oxide nanocomposite (XGX-g-PAAHs@CuO NC) has been successfully synthesized using the hydrothermal technique. This study focuses on the application of the XGX-g-PAAHs@CuO nanocomposite for the removal of methylene blue (MB dye) from synthetic wastewater. The synthesized nanocomposite has been used for dual purposes, i.e. for the adsorption and subsequent photocatalytic degradation of MB dye. The two processes, i.e. adsorption and photocatalytic degradation, are independent and occur in succession. After the first process of adsorption, the adsorbed methylene blue dye gets degraded photo-catalytically in the presence of visible light. Photocatalytic degradation and adsorption have been demonstrated as highly effective techniques for dye removal, offering the benefits of simplicity and cost-efficiency. The XGX-g-PAAHs@CuO NC have been characterized via UV/Vis, FTIR, PZC, TGA, XRD, SEM and BET studies. It was discovered that the nanocomposite's structure was amorphous and porous. MB dye adsorption from wastewater was studied at pH of 7, time duration of 30 min, with original dye concentration of 100 mg/L, adsorbent dosage of 1.2 g/L and temperature of 25°C, respectively. It was found that the adsorption kinetics follows pseudo-second order kinetics model. Langmuir isotherm fits with experimental data, having monolayer adsorption capacity to be 132.10 mg/g at 25°C. Thermodynamic analysis confirms that the adsorption process is spontaneous, exothermic and associated with decreased randomness. XGX-g-PAAHs@CuO NC shows efficient photocatalytic activity and degradation of MB dye reached 83.73% with the NCs under visible light after 40 min in the presence of synthesized NC. The synthesized adsorbent is reusable for five consecutive cycles, maintaining 90.2% adsorption efficiency and 89.1% desorption efficiency in the fifth cycle. Therefore, these experimental results confirm that XGX-g-PAAHs@CuO NC serve as an effective photocatalyst suitable for treating wastewater containing MB dye.