Department of Environmental Health Engineering, School of Health, Hamadan University of Medical Sciences, Hamadan, Iran.
Environ Sci Pollut Res Int. 2019 Mar;26(9):8914-8927. doi: 10.1007/s11356-019-04382-0. Epub 2019 Feb 4.
In this study, thermochemical degradation of furfural by sulfate radical has been investigated to find the best-operating conditions. For this purpose, the response surface methodology (RSM) based on central composite design (CCD) was applied to optimize the five independent variables of thermally activated persulfate (TAP)/nZVI oxidation process including pH, PS concentration, furfural concentration, nZVI dosage, and heat. The ANOVA results ("P > F value" < 0.0001 and [Formula: see text] = 0.9701) showed the obtained quadratic model is acceptable to predict furfural removal. Based on the reduced quadratic model PS concentration, nZVI dosage, and heat revealed the positive effects on removal efficiency, while pH and furfural concentration had a negative effect. Accordingly, 98.4% of furfural could be removed within 60 min of reaction under the optimum conditions: pH 5.26, PS concentration of 20.52 mM, furfural concentration of 84.32 mg/L, nZVI dosage of 1.15 mg/L, and a temperature of 79 °C. In such circumstances, the furfural removal efficiency for TAP, PS/nZVI, PS, and nZVI was 94.5, 9, 3, and 2%, respectively. Therefore, based on the synergy index (SI) values, the combination of PS, nZVI, and heat can lead to a synergistic effect in the performance of the thermochemical process.
在这项研究中，通过硫酸盐自由基的热化学降解来研究糠醛，以找到最佳的操作条件。为此，应用基于中心复合设计（CCD）的响应面法（RSM）来优化热激活过硫酸盐（TAP）/nZVI 氧化过程的五个独立变量，包括 pH、PS 浓度、糠醛浓度、nZVI 剂量和热量。方差分析（"P > F 值"< 0.0001 和 [Formula: see text] = 0.9701）表明，所得到的二次模型可以接受，用于预测糠醛去除率。根据简化的二次模型，PS 浓度、nZVI 剂量和热量对去除效率有积极影响，而 pH 和糠醛浓度则有负面影响。因此，在最佳条件下（pH 5.26、PS 浓度 20.52 mM、糠醛浓度 84.32 mg/L、nZVI 剂量 1.15 mg/L 和温度 79°C），反应 60 分钟内可以去除 98.4%的糠醛。在这种情况下，TAP、PS/nZVI、PS 和 nZVI 的糠醛去除效率分别为 94.5%、9%、3%和 2%。因此，根据协同指数（SI）值，PS、nZVI 和热量的组合可以在热化学过程的性能中产生协同效应。
