Fundamental studies for chemical speciation of iron in seawater with an improved analytical method
Fundamental studies for chemical speciation of iron in seawater with an improved analytical method
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采用改进的分析方法对海水中铁的化学形态进行基础研究
DOI：
10.1016/s0304-4203(96)00082-5
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发表时间：
1997
期刊：
影响因子：
3
通讯作者：
E. Nakayama
中科院分区：
文献类型：
--
作者：
H. Obata;H. Karatani;M. Matsui;E. Nakayama
在建立的分析方法的基础上，对海水中铁的分析方法进行了改进，并对铁的化学形态进行了基础研究。所用系统的空白值为0.05nM，检测限（3SD）为0.01nM。为了研究海水中悬浮颗粒铁的溶解，使用了四种类型的颗粒（老化铁胶体，生物颗粒，沉积物颗粒和新鲜沉积的铁）。在pH = 1.3时，铁从悬浮颗粒的易浸出部分中迅速溶解，铁的部分[总溶解铁，TD（Fe）]被认为是不稳定颗粒和溶解铁的总和。当溶液在微波炉中加热时，从溶液中的悬浮颗粒溶解的铁部分在pH < 1.5时是恒定的。通过该程序溶解的铁的分数被定义为“可浸出铁，L（Fe）"。一些已知的有机络合剂也进行了研究，作为一个模型组，以检查天然存在的有机配体的螯合树脂富集回收铁的可能影响。建立的方法被应用于分析从西南印度洋（SIO）和中国东海的海水样品。SIO的表层海水样本显示铁浓度非常低，这可能是由于缺乏矿物粉尘的风成运输。
We improved the analytical methods for determining iron in seawater, based on our established procedure, and carried out fundamental studies for chemical speciation of iron. The blank value of the system used was ∼ 0.05 n M and the detection limit (3 SD) was 0.01 n M. To examine the dissolution of iron from suspended particles in seawater, four types of particles (aged iron colloid, biogenic particles, sediment particles and freshly deposited iron) were used. At a pH of ∼ 3, dissolution of iron from the easily leachable fraction of suspended particles was prompt, and the fraction of iron [total dissolvable iron, TD(Fe)] was thought to be the sum of labile particulate and dissolved iron. The iron fractions dissolved from suspended particles in the solutions were constant at pHs < 1.5 when solutions were heated in a microwave oven. The fraction of iron dissolved by this procedure was defined as the “leachable iron, L(Fe)”. Some known organic complexing agents were also studied as a model group to examine the possible effects of naturally occurring organic ligands on the recovery of iron with chelating resin preconcentration. Established methods were applied to analyses of seawater samples obtained from the western Southern Indian Ocean (SIO) and the East China Sea. Surface seawater samples from the SIO showed very low iron concentrations, which may be due to a lack of aeolian transport of mineral dust.