Photocatalytic degradation of Azo Dye with encapsulated Zinc oxide

Abstract

Wastewater from textile dyeing and food processing contains high concentration of coloring agent which is infamous for their difficulties to degrade and remove. Dye molecule in water body is highly visible at low concentration and upon release to the water course, accumulation of dye molecule on plants root and soil component. This problem will eventually affect living aspect from aesthetical value to economy sector. This study was a partially studies on photocatalytic degradation of azo dye with encapsulated Zinc Oxide where the zinc oxide, photocatalyst was entrapped with sodium alginate to forms immobilize gel beads. This study focused on the effect of sodium alginate ratio, calcium chloride ratio, and zinc oxide ratio on loading efficiency and its recyclability. The result shows that 4% ratio of sodium alginate and zinc oxide with 7% ratio of calcium chloride able to degrade AR18 and RB5 dye solution, and at the same time been reuse for five times. The produce bead was then applied to the different dye concentration. The photo-degradation of AR18 and RB5 were well fitted with the Langmuir-Hinshelwood kinetic model for 10 and 30 mg/L and pseudo-firstorder rate constant of RB5 were significantly higher than the AR18.