Galeas Salomé, Guerrero Víctor H, Pontón Patricia I, Goetz Vincent
Doctoral School Energy and Environment, University of Perpignan Via Domitia (UPVD), 52 Avenue Paul Alduy, 66100 Perpignan, France.
PROMES-CNRS UPR 8521, PROcesses Materials and Solar Energy, Rambla de la Thermodynamique, 66100 Perpignan, France.
Molecules. 2025 May 6;30(9):2059. doi: 10.3390/molecules30092059.
Ferrous oxalate dihydrate (α-FOD) was synthesized from Ecuadorian black sands for phenol removal from aqueous solutions. Visible light-driven photodegradation kinetics were studied by varying the initial pollutant concentration, solution pH, and α-FOD dosage and by adding peroxydisulfate (PDS), including quenching tests. A representative model of phenol photodegradation was obtained by the Langmuir-Hinshelwood mechanism over a large range of concentrations (apparent kinetic constant, k = 0.524 h). Almost complete removal was reached within 1 h under dark + 9 h under visible irradiation. The degradation rate was slightly affected by pH in the range of 3 to 9, with a significant improvement at pH 11 (k = 1.41-fold higher). The optimal α-FOD dosage was ~0.5 g/L. Two regimes were observed when using PDS: first, a heterogeneous Fenton-like process during the first few minutes after PDS addition; second, pure photocatalysis to completely remove the phenol. When comparing the two systems, without and with PDS, the half-life time for pure photocatalysis was 2.5 h (after the lamp was switched on). When adding PDS (1.0 mM), the half-life time was reduced to a few minutes (5 min after PDS addition, phenol removal was 66%). The photocatalyst presented remarkable degradation efficiency up to five repeated cycles.
以厄瓜多尔黑砂为原料合成了二水合草酸亚铁（α-FOD），用于从水溶液中去除苯酚。通过改变初始污染物浓度、溶液pH值、α-FOD用量以及添加过二硫酸盐（PDS）并进行猝灭试验，研究了可见光驱动的光降解动力学。通过Langmuir-Hinshelwood机理在较大浓度范围内获得了苯酚光降解的代表性模型（表观动力学常数，k = 0.524 h）。在黑暗中1小时加上可见光照射9小时内几乎可实现完全去除。在3至9的pH范围内，降解速率受pH值的影响较小，在pH 11时显著提高（k高1.41倍）。最佳α-FOD用量约为0.5 g/L。使用PDS时观察到两种情况：第一，添加PDS后的最初几分钟内是类非均相芬顿过程；第二，是完全去除苯酚的纯光催化过程。比较有无PDS的两种体系时，纯光催化的半衰期为2.5小时（灯开启后）。添加PDS（1.0 mM）时，半衰期缩短至几分钟（添加PDS后5分钟，苯酚去除率为66%）。该光催化剂在五个重复循环中均表现出显著的降解效率。
