Highly enhanced dephosphorylation of phytic acid via pre-complexation of PA-Fe2+ in the Fenton system: High activity, wide pH range and ferryl-based mechanism
Highly enhanced dephosphorylation of phytic acid via pre-complexation of PA-Fe2+ in the Fenton system: High activity, wide pH range and ferryl-based mechanism
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通过 Fenton 体系中 PA-Fe2 的预络合高度增强植酸脱磷酸：高活性、宽 pH 范围和基于 Ferryl 的机制
DOI：
10.1016/j.cej.2021.130894
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发表时间：
2021-06-23
影响因子：
15.1
通讯作者：
Yao，Jun
中科院分区：
文献类型：
--
作者：
Qian，Yiguang;Pan，Weijie;Yao，Jun
通过有机磷（OP）的分解回收磷（P）对于防止水体富营养化和磷资源的可持续发展至关重要。本研究首次提出了利用改进的芬顿进行植酸的高效非生物脱磷。研究发现，PA与Fe ~（2+）的预络合不仅使芬顿反应的催化性能从33.4 ± 2.1%提高到76.3 ± 3.7%，而且使芬顿反应的pH（3.5-9.0）范围扩大到中性和碱性条件。在中性条件下，PA与Fe ~（2+）的预络合反应具有更高的芬顿反应活性（65.5 ± 1.2%，pH = 7.0）或碱性pH值为8.0和9.0时，其降解率分别为76.3 ± 3.7%和73.1 ± 2.1（在pH 3.6和6.0时分别为49.2 ± 2.4%和57.1 ± 4.3%）。这种显著的增强作用（p< 0.05）主要取决于PA-Fe ~（3+）的配位方式，并归因于铁循环的加速，Fe ~（3+）/Fe ~（2+）的氧化还原电位的降低，以及生成的铁基物种（PA-FeX= O，X表示高价态）作为主要反应物种。该改良芬顿体系对PA的降解是通过I（1，3，4，5，6）P5、I（1，4，5，6）P4或I（3，4，5，6）P4、I（4，5，6）P3、I（5，6）P2或I（4，5）P2和I（5）P1以逐步脱磷酸化的方式进行的。此外，这种改进的芬顿体系（PA-Fe 2 +/H2 O2）作为一种“广谱催化剂”，有望成为一种利用铁基物种降解自然环境中难降解有机污染物的新方法。
Phosphate (P) recovery through organic phosphorus (OP) decomposition is extremely crucial for prevention of water eutrophication and the sustainable development of P resources. In this work, for the first time, efficiently abiotic dephosphorylation of phytic acid (PA) through improved Fenton was proposed. The pre-complexation of PA with Fe2+are creatively revealed to not only enhance the catalytic performance of Fenton reaction to dephosphorylate PA from 33.4 ± 2.1% to 76.3 ± 3.7%, but also extend the pH (3.5–9.0) of Fenton reaction to neutral and alkaline conditions. The pre-complexation of PA with Fe2+exhibited much higher Fenton reactivity at neutral (65.5 ± 1.2% at pH = 7.0) or alkalescency (76.3 ± 3.7% and 73.1 ± 2.1% at pH of 8.0 and 9.0, respectively) condition than that at acid condition (49.2 ± 2.4% and 57.1 ± 4.3% at pH of 3.6 and 6.0, respectively). Such significant enhancement (p< 0.05) was mainly dependent on the coordination schemes for the complex PA-Fe3+, and ascribed to the accelerated iron cycle, the decreased redox potential of Fe3+/Fe2+, and the generated ferryl species (PA-FeX= O, X means high valence) as main reactive species. PA degradation by this improved Fenton system occurred in a stepwise dephosphorylation manner via I(1,3,4,5,6)P5, I(1,4,5,6)P4 or I(3,4,5,6)P4, I(4,5,6)P3, I(5,6)P2 or I(4,5)P2, and I(5)P1. Furthermore, this improved Fenton system (PA-Fe2+/H2O2) could be a promising method for the attenuation of refractory organic pollutants through ferryl species in natural environment as a kind of “broad-spectrum catalyst”.