"Alexandru Ioan Cuza" University of Iasi, Dept. Interdisciplinary Research- Field Science, Iasi, 700107, Romania.
Diamond Light Source, Harwell Science and Innovation Campus, Didcot, OX11 0DE, Oxfordshire, United Kingdom.
J Hazard Mater. 2019 Mar 5;365:252-260. doi: 10.1016/j.jhazmat.2018.11.009. Epub 2018 Nov 5.
This study presents a multifaceted approach of Zn adsorption onto dry Fucus vesiculosus originating from the Irish Sea. Metal chemistry as well as algae surface charge properties were characterized before adsorption. Zn adsorption tests were run as function of: pH, algae concentration and metal source. A comparison with Co, Cd, and Cu adsorption - in mono-ion solutions was also performed. Adsorption kinetics, fitted with pseudo-first order (PFO) and pseudo-second order (PSO) kinetic model, allowed the uptake parameters to be found and a comparison of kinetic rates. Synchrotron X-Ray-Florescence and X-Ray Absorption Spectroscopy measurements of Zn on algae after exposure permitted the extraction of direct information about Zn spatial distribution and bonding environment. The results showed that the carboxylic groups are the ones involved in the heterogeneously distributed Zn adsorption at low pH, Zn being coordinated with 5-6 O at bond distances varying from 1.98 to 2.03 Å - as in Zn alginate. Synchrotron results provide confirmation that, relative to Zn, alginate is one of the main algae components responsible for metal binding.
本研究提出了一种多方面的方法，用于研究源自爱尔兰海的干燥泡叶藻对锌的吸附。在吸附之前，对金属化学性质和藻类表面电荷特性进行了表征。进行了 Zn 吸附测试，作为 pH、藻类浓度和金属源的函数。还对 Co、Cd 和 Cu 在单离子溶液中的吸附进行了比较。吸附动力学拟合伪一级（PFO）和伪二级（PSO）动力学模型，可找到吸收参数并比较动力学速率。对暴露于藻类后的 Zn 进行同步加速器 X 射线荧光和 X 射线吸收光谱测量，可提取有关 Zn 空间分布和键合环境的直接信息。结果表明，在低 pH 下，羧酸基团参与了不均匀分布的 Zn 吸附，Zn 与 5-6 个 O 配位，键距离在 1.98 到 2.03Å 之间-就像在 Zn 藻酸盐中一样。同步加速器结果证实，相对于 Zn，藻酸盐是负责金属结合的主要藻类成分之一。
