Effect of lignosulfonate on the adsorption performance of hematite for Cd(II)
Effect of lignosulfonate on the adsorption performance of hematite for Cd(II)
复制标题
木质素磺酸盐对赤铁矿对Cd(II)吸附性能的影响
DOI：
10.1016/j.scitotenv.2020.139952
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发表时间：
2020-10-10
影响因子：
9.8
通讯作者：
Zhou, Yangmei
中科院分区：
文献类型：
--
作者：
Liu, Qianjun;Tang, Jiepeng;Zhou, Yangmei
木质素是土壤和沉积物中腐殖质的前体。木质素可以通过制浆工艺以木质素磺酸盐的形式从维管植物中分离出来。另一方面，铁氧化物与有机质的复合物可以吸附重金属，从而影响重金属在环境中的迁移。采用共沉淀法制备了赤铁矿/木质素磺酸盐复合材料（HLS），比较了掺入木质素磺酸盐（LS）前后赤铁矿（α-Fe 2 O3）对Cd（II）的吸附性能。发现HLS表现出弱结晶结构，并具有大量的纳米级颗粒。HLS的比表面积（291.97 m2/g）约为α-Fe 2 O3的11倍，孔体积（0.22 cm 3/g）约为α-Fe 2 O3的2倍。HLS对Cd（II）的吸附符合准二级吸附动力学，初始吸附速率（h）是α-Fe 2 O3的13.83倍。最大吸附容量从4.89-6.35 mg/g（α-Fe_2 O_3）提高到39.03-53.65 mg/g（HLS）。通过拟合模型，发现Cd（II）与HLS之间有更强的亲和力和更好的缔合作用.通过FT-IR和XPS表征进一步证实了LS的加入使HLS-Fe_2 O_3对Cd（II）的吸附性能明显优于α-Fe_2 O_3。吸附过程主要受配位键络合作用的影响，吸附剂中存在Fe-O-O-H和Fe-O-H结构以及较多的羟基，从而提高了吸附性能。(C)2020爱思唯尔B. V.保留所有权利。
Lignin is a precursor of humus in soil and sediment. Lignin can be separated from vascular plants in the form of lignosulfonate via pulping processes. On the other hand, composites of iron oxide and organic matter can adsorb heavymetals, and thus influence the migration of these heavymetals in the environment. In this paper, a hematite/lignosulfonate composite (HLS) was prepared via coprecipitation to compare the adsorption performance of hematite (alpha-Fe2O3) toward Cd(II) before and after the incorporation of lignosulfonate (LS). The HLS is found to exhibit a weakly crystalline structure and possess a large number of nanoscale particles. Specific surface area of HLS (291.97 m(2)/g) is about 11 times that of alpha-Fe2O3, and the pore volume of HLS (0.22 cm(3)/g) is twice that of alpha-Fe2O3. The adsorption of Cd(II) is well illustrated by the pseudo-second-order adsorption kinetics and the initial adsorption rate (h) of HLS is 13.83 times that of alpha-Fe2O3. The maximum adsorption capacities are significantly improved from 4.89-6.35 mg/g (alpha-Fe2O3) to 39.03-53.65 mg/g (HLS). A greater affinity and more favorable association between Cd(II) and HLS is observed via fittingmodels. The incorporation of LS provides HLSwith significantly better adsorption properties toward Cd(II) than alpha-Fe2O3, as is further confirmed by FT-IR and XPS characterization. Fe-O-O-H and Fe-O-H structures as well as more hydroxyl groups are observed, which promote the adsorption performance since the process are mainly influenced by complexation via coordination bonds. (C) 2020 Elsevier B.V. All rights reserved.