Photo-stability of iron-phenolic complexes derived from peatland upon irradiation in waters under simulated sunlight

摘要: Abstract Phenolics from peatlands have been proven to enhance the solubility of iron, even under alkali or saline conditions, by forming iron-phenolic complexes. However, photo-stability these complexes has received little attention thus far. Based on investigation water and peat samples in Jinchuan peatland, northern China, simulated experiments – using Gallic acid (GA) as a structural analog peat-derived phenolic were carried out clarify mechanisms Our research confirmed that when molar ratio GA Fe reaches 0.1:1, photolysis led some deposition. By comparing concentrations aerobic/anaerobic we demonstrated dissolved oxygen plays key role, not only autoxidation but also photo-degradation through direct indirect photolysis. Besides, adding coexisting acids into GA/iron systems showed various effects, depending different functional groups, while dominant species peatlands, such p-cumaric p-hydroxybenzoic acid, may still act reactive scavengers, protecting over 99% iron solar irradiation. results indicate iron-organic with certain phenolics can be effectively protected precipitation during freshwater transport irradiation, which profound implications for controlling limited primary production marine areas.