Ahmad Mushtaq, Asghar Anam, Abdul Raman Abdul Aziz, Wan Daud Wan Mohd Ashri
Department of Chemical Engineering, Faculty of Engineering, University of Malaya, 50603, Kuala Lumpur, Malaysia.
PLoS One. 2015 Oct 30;10(10):e0141348. doi: 10.1371/journal.pone.0141348. eCollection 2015.
Fenton oxidation, an advanced oxidation process, is an efficient method for the treatment of recalcitrant wastewaters. Unfortunately, it utilizes H2O2 and iron-based homogeneous catalysts, which lead to the formation of high volumes of sludge and secondary pollutants. To overcome these problems, an alternate option is the usage of heterogeneous catalyst. In this study, a heterogeneous catalyst was developed to provide an alternative solution for homogeneous Fenton oxidation. Iron Zeolite Socony Mobile-5 (Fe-ZSM-5) was synthesized using a new two-step process. Next, the catalyst was characterized by scanning electron microscopy, energy-dispersive X-ray spectroscopy, fourier transform infrared spectroscopy, and Brunauer-Emmett-Teller analysis and tested against a model wastewater containing the azo dye Acid Blue 113. Results showed that the loading of iron particles reduced the surface area of the catalyst from 293.59 to 243.93 m2/g; meanwhile, the average particle size of the loaded material was 12.29 nm. Furthermore, efficiency of the developed catalyst was evaluated by performing heterogeneous Fenton oxidation. Taguchi method was coupled with principal component analysis in order to assess and optimize mineralization efficiency. Experimental results showed that under optimized conditions, over 99.7% degradation and 77% mineralization was obtained, with a 90% reduction in the consumption of the developed catalyst. Furthermore, the developed catalyst was stable and reusable, with less than 2% leaching observed under optimized conditions. Thus, the present study proved that newly developed catalyst has enhanced the oxidation process and reduced the chemicals consumption.
芬顿氧化法作为一种高级氧化工艺，是处理难降解废水的有效方法。遗憾的是，该方法使用过氧化氢和铁基均相催化剂，会导致大量污泥和二次污染物的形成。为克服这些问题，一种替代方案是使用非均相催化剂。在本研究中，开发了一种非均相催化剂，为均相芬顿氧化提供替代解决方案。采用一种新的两步法合成了铁沸石Socony Mobile-5（Fe-ZSM-5）。接下来，通过扫描电子显微镜、能量色散X射线光谱、傅里叶变换红外光谱和布鲁诺尔-埃米特-泰勒分析对催化剂进行表征，并针对含有偶氮染料酸性蓝113的模拟废水进行测试。结果表明，铁颗粒的负载使催化剂的比表面积从293.59降至243.93 m²/g；同时，负载材料的平均粒径为12.29 nm。此外，通过进行非均相芬顿氧化评估了所开发催化剂的效率。将田口方法与主成分分析相结合，以评估和优化矿化效率。实验结果表明，在优化条件下，降解率超过99.7%，矿化率达到77%，所开发催化剂的消耗量减少了90%。此外，所开发的催化剂稳定且可重复使用，在优化条件下观察到的浸出率低于2%。因此，本研究证明新开发的催化剂增强了氧化过程并减少了化学药剂的消耗。
