Application, optimisation and kinetic studies of SnO micro-square in photoinduced decolourisation of Acid Orange 7 and Acid Orange 10 under visible light irradiation

ABSTRACT

In this study, SnO micro-square was prepared from the reaction between Tin(II) chloride and sodium hydroxide in 1:4 molar ratio under reflux condition without calcination. The characterisation of the product was carried out by Fourier-transform infrared, X-ray powder diffraction (XRD), scanning electron microscopy and energy-dispersive X-ray spectroscopy. XRD pattern showed the formation of α-SnO tetragonal lattice structure with orientation in (001), (101), (110), (002), (200), (112) and (103) planes at 18.39, 29.86, 33.30, 37.27, 47.91, 50.83 and 57.40° values. Then, the photoinduced decolourisation of Acid Orange 7 (AO7) and Acid Orange 10 (AO10) was studied using SnO. The effect of parameters such as pH, photocatalyst amount, initial dye concentration and contact time was studied. The final results showed that by the addition of SnO (0.04 g) to AO7 (5 ppm) at pH 5 and SnO (0.05 g) to AO10 (5 ppm) at pH 6, the highest decolourisation percentage 93.0% and 70.4% for AO7 and AO10 dyes can be achieved. The rate of photoinduced decolourisation of AO7 and AO10 in the presence of SnO was obeyed by the first-order kinetic models.

KEYWORDS:

• SnO
• micro-square
• decolourisation
• Acid Orange 7
• Acid Orange 10

Disclosure statement

No potential conflict of interest was reported by the authors.