The textile industry is one of the fastest-growing industries that significantly contribute to the economic growth in Malaysia. Dyeing wastewater is one of the more difficult to control in industrial wastewater. Methylene blue is a widely used dye in the textile industry, which cannot be discharged directly into the natural environment without treatment. The present study involves the degradation of methylene blue by a Fenton-like system using calcium peroxide (CaO₂, CP). The process of degradation was recorded spectrophotometrically. The field emission scanning electron microscope (FESEM) and energy dispersive X-ray (EDX) were measured for testing the purchased commercial calcium peroxide. The effect of pH, the initial dosage of CaO₂, and temperatures were studied with kinetics modeling, respectively. The results indicated that 97.07% removal of methylene blue took place at the optimum condition (pH=3.0, initial CaO₂, dosage=3.0 g, 65°C, 150 rpm, contact time=60 minutes). Over four models (zero-order, first-order, second-order, Behnajady, Modirshahla, and Ghanbary (BMG) model) applied in this study, the BMG model with the R2=0.9935 was in accordance with the experimental data.

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