Green Synthesis of Azolla Pinnata Extract Nanoparticles for Nickel Removal from Industrial Wastewater: An Optimization Study

Abstract:

Azolla pinnata extract and iron chloride were combined under optimized conditions using Response Surface Methodology (RSM) to synthesize Azolla pinnata-iron oxide nanoparticles (AP-IONPs). The study investigated the effects of three key parameters mixing ratio of iron chloride to Azolla pinnata extract (v/v), solution pH, and mixing temperature on the removal efficiency of nickel (Ni²⁺) ions from aqueous solutions. A Central Composite Design (CCD) was employed to develop two-factor interaction (2FI) and quadratic models describing the influence of these variables on nanoparticle synthesis and adsorption performance. Analysis of Variance (ANOVA) was used to determine the most significant factors affecting Ni removal. The optimal synthesis conditions were identified as a mixing ratio of 2.5:1, solution pH of 2.5, and a temperature of 70 °C. Under these conditions, the predicted and experimental Ni removal efficiencies were 98.1% and 97.1%, respectively, with a prediction error of just 1.02%. Keywords: Green synthesis; Response surface methodology; Azolla pinnata; Nanoparticles Heavy metals; Nickel; Adsorption.

• Periodical: Advanced Materials Research (Volume 1186)
• Pages: 107-117
• DOI: https://doi.org/10.4028/p-Xzy3q1
• Online since: January 2026
• Authors: Alaa Jasim Mohammed, Ferdius Mohamat Yusuff, Jassim Mohammed Salman*
• Keywords: Adsorption, Azolla Pinnata, Green Synthesis, Nanoparticles Heavy Metals, Nickel, Response Surface Methodology

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