摘要:In this study, the degradation of methylene blue (MB) and acid orange II (ORII) by the Fenton reaction was improved by using HCl and HNO3. In addition, the effects of pH, temperature, concentration of Fenton’s reagent, and adjustment reagent of solution pH on the decoloration were evaluated. The results showed that the optimal pH for decoloration of MB and ORII was 2.5 and that the decoloration of MB and ORII increased with higher temperature and concentration of Fenton’s reagent. Moreover, the decoloration in the Fenton-reaction process with HCl and HNO3 was greater than the decoloration with H2SO4 by approximately 4.3–5.6 and 1.7–5.6 times for MB and 3.2–3.6 and 4.6–7.2 times for ORII compared to with H2SO4. These results indicated that Fenton-reaction with HCl and HNO3 could be useful for the degradation technology of dyes compared to generally Fenton-reactions.