新穎材料農業：友善環境農業新穎材料研發與安全評估【土壤環境科學系劉雨庭助理教授】

論文篇名 英文：Phosphate removal in relation to structural development of humic acid-iron coprecipitates
中文：磷酸根移除與腐植酸-鐵共沉澱物結構發展之關係
期刊名稱 Scientific Reports
發表年份,卷數,起迄頁數 2018, 8, 10363
作者 Chen, K.Y., Hsu, L.C., Chan, Y.T., Cho, Y.L., Tsao, F.Y., Tzou, Y.M.(鄒裕民), Hsieh, Y.C., Liu, Y.T.*(劉雨庭)
DOI 10.1038/s41598-018-28568-7
中文摘要 鐵氫氧化物的沉澱通常顯著的影響磷酸根及有機質的吸存。雖然預先吸附的有機質會包覆進而減少鐵氫氧化物表面可以吸附磷酸根的位置，然而相關的機制研究卻付之闕如。本篇研究目的為利用鐵及磷的X 光吸收光譜，觀察不同腐植酸種類及碳鐵比所合成的腐植酸-鐵共沉澱物表面及結構特性與如何影響其對磷酸根的吸附行為。結果顯示，隨著碳鐵比增加，含有較多極性官能基腐植酸的共沉澱物中，其表面碳的比例沒有明顯變化，暗示碳與鐵之間相對地均勻分布。停留在此共沉澱物上主要磷的物種為吸附在鐵氫氧化物上的磷酸根，產生的磷酸根吸持特性與純鐵氫氧化物幾乎相同。在此共沉澱物中，鐵氫氧化物與腐植酸的極性官能基有很強的連結，導致其結構的破壞進而增加碳的溶出。對於含有較少極性官能基腐植酸的共沉澱物，其共沉澱物結構主要由鐵氫氧化物的核心與附著在表面的腐植酸所組成。儘管附著在表面的腐植酸可藉由鐵離子橋接與磷酸根結合，其不穩定且容易溶出的狀態最終導致此共沉澱物的磷酸根吸附量的減少。
英文摘要 Precipitation of Fe-hydroxide (FH) critically influences the sequestration of PO4 and organic matter (OM). While coatings of pre-sorbed OM block FH surfaces and decrease the PO4 adsorption capacity, little is known about how OM/Fe coprecipitation influences the PO4 adsorption. We aimed to determine the PO4 adsorption behaviors on humic acid (HA)-Fe coprecipitates in relation to surface and structural characteristics as affected by HA types and C/(C Fe) ratios using the Fe and P X-ray absorption spectroscopy. With increasing C/(C Fe) ratios, the indiscernible changes in the proportion of near surface C for coprecipitates containing HA enriched in polar functional groups implied a relatively homogeneous distribution between C and Fe domains. Wherein PO4 adsorbed on FH dominated the P inventory on coprecipitates, yielding PO4 sorption properties nearly equivalent to that of pure FH. Structural disruptions of FH caused by highly associations with polar functional groups of HA enhanced the C solubilisation. While polar functional groups were limited, coprecipitates consisted of core FH with surface outgrowth of HA. Although surface-attached HA that was vulnerable to solubilisation provided alternatively sites for PO4 via ternary complex formation with Fe bridges, it also blocked FH surfaces, leading to a decrease in PO4 adsorption.