Bali Ulusoy, Catalkaya Ebru C, Sengül Füsun
Department of Environmental Engineering, Engineering Faculty, Dokuz Eylül University, Kaynaklar Campus, Buca-Izmir, Turkey.
J Environ Sci Health A Tox Hazard Subst Environ Eng. 2003;38(10):2259-75. doi: 10.1081/ese-120023373.
In this study, photochemical advanced oxidation processes (AOPs) utilizing the combinations of UV, UV/H2O2, and UV/H2O2/Fe2+ (Photo-Fenton process) were investigated in lab-scale experiments for the degradation and mineralization of phenol. The major parameters investigated were the initial phenol concentration, pH, hydrogen peroxide, and iron doses, and the effect of the presence of radical scavengers (PO4(-3), SO4(-2), and Cl- ions). It was observed that the phenol degradation efficiency decreased with increasing phenol concentration and pH in UV process. Maximum phenol oxidation efficiency for an initial concentration of 100 mg L(-1) and at pH 3 was around 30% in direct photolysis. The efficiency increased to 97% with UV/H2O2 process, however, there was still negligible mineralization (9%) and the required irradiation time was still long (300 min). The results showed that the Photo-Fenton process was the most effective treatment process under acidic conditions. Complete disappearance of 100 mg L(-1) phenol was achieved in 2.5 min and almost complete mineralization (97%) was also possible after 300 min of irradiation. The efficiency was negatively affected from H2O2 in UV/H2O2 process and Fe2+ in Photo-Fenton process over a certain concentration. The highest negative effect was observed with solution containing PO4(-3) ions. Required reaction time for complete disappearance of 100 mg L(-1) phenol increased from 2.5 min for an ion-free solution to 60 min for that containing PO4(-3). The photodegradation of phenol was found to follow the first-order law.
在本研究中，在实验室规模的实验中研究了利用紫外线、紫外线/过氧化氢和紫外线/过氧化氢/亚铁（光芬顿法）组合的光化学高级氧化过程（AOPs）对苯酚的降解和矿化作用。研究的主要参数有初始苯酚浓度、pH值、过氧化氢和铁的剂量，以及自由基清除剂（磷酸根离子、硫酸根离子和氯离子）存在的影响。观察到在紫外线过程中，苯酚降解效率随苯酚浓度和pH值的增加而降低。在直接光解中，初始浓度为100 mg L⁻¹且pH值为3时，苯酚的最大氧化效率约为30%。采用紫外线/过氧化氢工艺时，效率提高到97%，然而，矿化作用仍然可以忽略不计（9%），并且所需的辐照时间仍然很长（300分钟）。结果表明，在酸性条件下，光芬顿法是最有效的处理工艺。100 mg L⁻¹苯酚在2.5分钟内完全消失，辐照300分钟后几乎完全矿化（97%）也是可能的。在一定浓度以上，紫外线/过氧化氢工艺中的过氧化氢和光芬顿法中的亚铁对效率有负面影响。在含有磷酸根离子的溶液中观察到的负面影响最大。100 mg L⁻¹苯酚完全消失所需的反应时间从无离子溶液的2.5分钟增加到含有磷酸根离子溶液的60分钟。发现苯酚的光降解遵循一级定律。
