Oxidative degradation of2,4,6-trichlorophenol and pentachlorophenol in contaminated soil suspension using a supramolecular catalyst prepared via formaldehyde polycondensation between tetrakis(p-hydroxyphenyl)porphineiron(III) and humic acid
Oxidative degradation of2,4,6-trichlorophenol and pentachlorophenol in contaminated soil suspension using a supramolecular catalyst prepared via formaldehyde polycondensation between tetrakis(p-hydroxyphenyl)porphineiron(III) and humic acid
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四(对羟基苯基)卟吩铁(III)与腐殖酸甲醛缩聚制备的超分子催化剂氧化降解污染土壤悬浮液中的2,4,6-三氯苯酚和五氯苯酚
DOI：
10.1080/10934520903005053
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发表时间：
2009
期刊：
影响因子：
--
通讯作者：
S. Nagao
中科院分区：
文献类型：
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作者：
M. Fukushima;S. Shigematsu;S. Nagao
多环芳烃（PAHs）是一种普遍存在的有机污染物，在自然环境中具有持久性和对健康的不利影响。许多研究已经调查了这些污染物的去除和处理，结果好坏参半。高分子量多环芳烃由于其疏水性和对有机物的高亲和力而特别成问题，导致即使是最快的高级氧化过程（AOP）的传质限制。过氧酸工艺已成功用于处理多环芳烃污染基质。实验进行了苯并[a]芘污染的玻璃珠，以阐明负责该过程的有效性的反应机理。首次确定过氧乙酸（PAA）为该反应中的重要氧化剂。研究了过氧化氢/乙酸/去离子水的不同v/v/v比，说明了反应比对氧化剂浓度和形成速率的重要性。当PAA浓度为1.7%时，24 h内苯并[a]芘的降解率约为60%。反应动力学的观察表明，苯并[a]芘的缓慢解吸/溶解限制了过氧酸过程的效率。反应设置的修改支持这一观察，因为处理效率随着反应表面积的增加而增加，并且系统搅拌增加。这些限制也通过增加递送到污染基质的PAA的浓度来克服。苯并[a]芘的降解率在24小时内达到80%以上，PAA浓度约为9.2%。
Polycyclic aromatic hydrocarbons (PAHs) are organic contaminants of concern due to their ubiquity, persistence in the natural environment and adverse health effects. Numerous studies have looked into the removal and treatment of these contaminants, with mixed results. High molecular weight PAHs have been particularly problematic due to their hydrophobicity and high affinity for organics, resulting in mass transfer limitations for even the fastest advanced oxidation processes (AOPs). The peroxy-acid process has been used to successfully treat PAH contaminated matrices. Experiments were conducted on benzo[a]pyrene contaminated glass beads in order to elucidate the reaction mechanisms responsible for the effectiveness of this process. For the first time peracetic acid (PAA) was identified as the important oxidant in this reaction. Different v/v/v ratios of hydrogen peroxide/acetic acid/DI water were studied which illustrated the importance of reaction ratio on oxidant concentration and rate of formation. Approximately 60% degradation of benzo[a]pyrene was achieved in 24 hours with 1.7% PAA. Observations of the reaction kinetics suggest that the slow desorption/dissolution of benzo[a]pyrene limits the efficiency of the peroxy-acid process. Modifications of the reaction setup supported this observation as treatment efficiencies increased with reactive surface area, and an increase in system agitation. These limitations were also overcome by increasing the concentration of PAA delivered to the contaminated matrix. Greater than 80% degradation of benzo[a]pyrene was achieved in 24 hours with approximately 9.2% PAA.