Enhanced phosphate removal using zirconium hydroxide encapsulated in quaternized cellulose
Enhanced phosphate removal using zirconium hydroxide encapsulated in quaternized cellulose
复制标题
使用封装在季铵化纤维素中的氢氧化锆增强除磷能力
DOI：
10.1016/j.jes.2019.10.005
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发表时间：
2020-03-01
影响因子：
6.9
通讯作者：
Qu, Jiuhui
中科院分区：
文献类型：
--
作者：
Dong, Shuoxun;Ji, Qinghua;Qu, Jiuhui
锆基材料是去除水中磷酸盐的高效吸附剂。然而，目前的锆基材料在吸附容量和选择性方面仍表现不佳。在此，我们展示了一种季铵化纤维素包覆氢氧化锆（QCeZr）用于选择性去除磷酸盐。氢氧化锆纳米粒子与季铵化纤维素（QC）骨架同时原位生成，并牢固地锚定在三维（3D）交联的纤维素链中。QCeZr对磷的最大吸附量为83.6毫克磷/克。此外，由于季铵化纤维素的静电作用，QCeZr在较宽的pH范围内都表现出较高的磷吸附性能。即使在竞争阴离子（包括Cl⁻、NO₃⁻、SO₄²⁻、SO₄⁴⁻）和腐殖酸（HA）存在的情况下，甚至在摩尔比高达20的水平时，磷的吸附也得到了增强。当磷浓度从2.5毫克/升降至0.5毫克/升，在空床接触时间（EBCT）为0.5分钟时，QCeZr的柱吸附量达到4000倍床体积（BV）。机理研究表明，季铵（CH₃）₃基团和氢氧化锆都通过季铵（CH₃）₃与磷酸盐之间的静电相互作用以及磷酸氢锆（Zr(HPO₄)ₓ）的形成参与了磷酸盐的吸附。磷 - 31核磁共振（NMR）研究表明，磷在表面沉淀以及与氢氧化锆形成内圈络合物的比例为3∶1。（c）2019中国科学院生态环境研究中心。由爱思唯尔出版集团出版。
注：原文中“SO₄⁴⁻”可能有误，一般硫酸根离子为“SO₄²⁻”。
Zirconium-based materials are efficient adsorbent for aqueous phosphate removal. However, current zirconium-based materials still show unsatisfied performance on adsorption capacity and selectivity. Here, we demonstrate a zirconium hydroxide encapsulated in quaternized cellulose (QCeZr) for the selective phosphate removal. Zirconium hydroxide nanoparticles were simultaneously generated in situ with the QC framework and firmly anchored in the three-dimensional (3D) cross-linked cellulose chains. The maximum P adsorption capacity of QCeZr was 83.6 mg P/g. Furthermore, the QCeZr shows high P adsorption performance in a wide pH range, generally due to the electrostatic effects of quaternized cellulose. The enhanced adsorption of P was also achieved in the presence of competing anions (including Cl-, NO3-, SO42-, SO44-) and humic acid (HA) even at a molar ratio up to 20 levels. The column adsorption capacity of QCeZr reached 4000 bed volumes (BV) at EBCT = 0.5 min as the P concentration decreased from 2.5 to 0.5 mg/L. Mechanism study revealed that both eNthorn (CH3)(3) groups and zirconium hydroxide were involved in phosphate adsorption via electrostatic interactions between eNthorn (CH3)(3) and phosphate, and the formation of zirconium hydrogen phosphate (Zr(HPO4)(x)). The P-31 nuclear magnetic resonance (NMR) study implied that P surfaceeprecipitated and inneresphere complexed with zirconium hydroxide at a ratio of 3:1. (c) 2019 The Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V.