Photocatalytic degradation of Acid Red 88 dye using Pd@TMU-16 metal organic framework

ABSTRACT

The objective of this study was to investigate the performance of the Pd@TMU-16 to act as a photocatalyst in degrading the Acid Red 88 (AR88) dye from an aqueous solution, via photocatalysis process, using UV irradiation. The synthesis of this catalyst was performed under conditions of thermal solvent and its characteristic parameters were confirmed using the XRD, Band gap, SEM, BET, pH_PCZ, and FTIR methodologies. The influence exerted by the operative parameters on the AR88 degradation, which included the pH, reaction time, radiation intensity, catalyst mass, and initial dye concentration was examined. At the optimum condition of photocatalysis and utilising only 0.75 g of Pd@TMU-16, total degradation of 10 mg/L dye concentration was performed. From the kinetic studies, the dye degradation indicated that it was similar to the pseudo-first-order model, and the dye degradation mechanism had taken place through the hydroxyl (^•OH) and superoxide radicals (^•O⁻₂). The adsorbent reusability was also studied, and from the results it was evident that the 18% decrease observed after six consecutive cycles of catalyst use, clearly indicated its stability. For radiation intensities of 8, 15, 24, and 36 W, the Energy Consumed per m³ of the treated wastewater was found 20.2, 28.8, 34.1, and 36.9 kWh, respectively. From these results, namely the low energy gap (2.3 eV) and high degradation capacity, it was evident that the Pd@TMU-16 can be useful, under UV light, as a powerful catalyst in the elimination of dyes and other organic contaminants from polluted aqueous media.

KEYWORDS:

• Metal-organic framework
• photocatalytic degradation
• Acid Red 88
• Pd@TMU-16
• kinetic study

Acknowledgments

The authors extend their gratitude to the Zahedan University of Medical Sciences (Iran) for the financial support and laboratory assistance provided to conduct this study (Design code:10643). Special thanks to the Al-Mustaqbal University College (Babylon, Iraq), for their efforts to accomplish this paper.

Disclosure statement

No potential conflict of interest was reported by the author(s).