Department of Environmental Engineering, Cukurova University, Adana, Turkey.
Environ Technol. 2023 Sep;44(21):3294-3315. doi: 10.1080/09593330.2023.2229943. Epub 2023 Jul 6.
Textile wastewater containing dyes poses significant risks to the environment. Advanced oxidation processes (AOPs) effectively eliminate dyes by converting them into harmless substances. However, AOPs have drawbacks such as sludge formation, metal toxicity, and high cost. As an alternative to AOPs, calcium peroxide (CaO) offers an eco-friendly and potent oxidant for dye removal. Unlike certain AOPs that generate sludge, CaO can be directly employed without resulting in sludge formation. This study examines the use of CaO for oxidizing Reactive Black 5 (RB5) in textile wastewater without any activator. Various independent factors-pH, CaO dosage, temperature, and certain anions-were investigated for their influence on the oxidation process. The effects of these factors on dye oxidation were analyzed using the Multiple Linear Regression Method (MLR). CaO dosage was determined to be the most influential parameter for RB5 oxidation, while the optimal pH for oxidation with CaO was found to be 10. The study determined that 0.5 g of CaO achieved approximately 99% efficiency in oxidizing 100 mg/L of RB5. Additionally, the study revealed that the oxidation process is endothermic, with an activation energy (Ea) and standard enthalpy (ΔH°) for RB5 oxidation by CaO determined as 31.135 kJ mol and 110.4 kJ mol, respectively. The presence of anions decreased RB5 oxidation, with decreasing effectiveness observed in the order of PO, SO, HCO, Cl, CO, and NO. Overall, this research highlights CaO as an effective, easy-to-use, eco-friendly, and cost-efficient method for removing RB5 from textile wastewater.
含染料的纺织废水对环境构成重大风险。高级氧化工艺（AOPs）通过将染料转化为无害物质，有效地消除染料。然而，AOPs 存在一些缺点，如污泥形成、金属毒性和高成本。作为 AOPs 的替代方法，过氧化钙（CaO）提供了一种环保且有效的氧化剂，可用于去除染料。与某些会产生污泥的 AOPs 不同，CaO 可以直接使用而不会产生污泥。本研究考察了在没有任何活化剂的情况下，CaO 用于氧化纺织废水中活性黑 5（RB5）的用途。研究了各种独立因素，如 pH 值、CaO 剂量、温度和某些阴离子，对氧化过程的影响。使用多元线性回归方法（MLR）分析了这些因素对染料氧化的影响。结果表明，CaO 剂量是 RB5 氧化的最主要影响因素，而 CaO 氧化的最佳 pH 值为 10。研究发现，0.5 g CaO 可将 100 mg/L 的 RB5 氧化至约 99%的效率。此外，研究还表明氧化过程是吸热的，CaO 氧化 RB5 的活化能（Ea）和标准焓（ΔH°）分别为 31.135 kJ/mol 和 110.4 kJ/mol。阴离子的存在会降低 RB5 的氧化效率，其降低效率的顺序为 PO、SO、HCO、Cl、CO 和 NO。总的来说，这项研究强调了 CaO 作为一种有效、易用、环保且经济高效的方法，可用于去除纺织废水中的 RB5。
