1. 沈阳师范大学生命科学学院，辽宁 沈阳 110031
2. Department of Soil and Crop Sciences, Colorado State University, Fort Collins, CO 80523, USA
3. 陕西科技大学环境科学与工程学院，陕西 西安 710021
Adsorption of Cadmium on Fe-Mn Nodules Derived From Soil by Spectral Methods
FAN Chun-hui1,2, ZHENG Jin-huan3, WANG Yu-fei3, SU Zhe3, LIN Long-jian3, YANG Chen3
1. College of Life Sciences, Shenyang Normal University, Shenyang 110031, China
2. Department of Soil and Crop Sciences, Colorado State University, Fort Collins, CO 80523, USA
3. School of Environmental Science and Engineering, Shaanxi University of Science and Technology, Xi’an 710021, China
Abstract：As clay minerals complex with high reactivity, Fe-Mn nodules in soil, with special geochemical characteristics, different from Fe-Mn nodules in the ocean, can always be found in drying-wetting cycle condition and water-air disturbing environment. Fe-Mn nodules, the new-formed component in the pedosphere, appear the various qualities in different regions. The investigation on adsorption behavior between soil Fe-Mn nodules and metals in the representative areas is helpful to understand further the micro-ecological property of Fe-Mn nodules and is significant for soil exploitation and utilization, conservation and improvement, and contamination remediation. It currently lacks the related research on soil Fe-Mn nodules in western China, while this paper might supply unclear information and improve the research level from a spectral aspect. Water-washing method was used and spectral analysis approaches of Inductively Coupled Plasma-Optical Emission Spectrometer (ICP-OES), Ultraviolet-Visible Spectroscopy (UV-Vis), X-Ray Diffractometer (XRD) and Fourier Transform Infrared Spectroscopy (FTIR) were applied to analyze the main elemental oxides and structure of Fe-Mn nodules in western China. Batch adsorption procedures were involved in study the reaction, and the effects of time, cadmium concentration and temperature were discussed. The kinetics equation and isotherms equations were used to fit the reaction, thermodynamic parameters were calculated, and the desorption experiments were studied. The dominant elemental oxides include Fe2O3, SiO2, Al2O3 and MnO, with the highest content of Fe2O3 followed by SiO2 in Fe-Mn nodules. Similar mineral components are found between Fe-Mn nodules and soil samples, and functional groups of —OH, Si—O—Si (Al) and Fe(Mn)—O appear in the FTIR spectrum. The adsorption is fast at the beginning of the reaction and then becomes slow gradually. The adsorption capacity (Q) reaches 4.96 mg·g-1 at 6 h, and changes little after 12 h. The increased concentration of cadmium leads to higher Q values, and temperature affects little the reaction. Pseudo-second order equation fit better with a higher coefficient of R2 (0.994 3), indicating the reaction rate might be controlled by chemical adsorption. The value of R2 (0.999 1) from the Langmuir equation, is higher than that from the Freundlich equation, suggesting the reaction belongs to the monolayer chemical adsorption. The reaction is spontaneous and endothermic, and complexation might be involved during the process. Positive S value suggests an increase in randomness during the interaction. The desorption efficiency is better with HCl solution (0.1 mol·L-1, prepared with tap water). The research is significant for mechanism analysis with spectral approaches in future.
范春辉， 郑金焕， 王宇飞， 苏 哲， 蔺龙健， 杨 晨. 基于光谱识别技术的土壤铁锰结核对镉的吸附行为研究[J]. 光谱学与光谱分析, 2022, 42(02): 616-621.
FAN Chun-hui, ZHENG Jin-huan, WANG Yu-fei, SU Zhe, LIN Long-jian, YANG Chen. Adsorption of Cadmium on Fe-Mn Nodules Derived From Soil by Spectral Methods. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2022, 42(02): 616-621.
[1] Rizwan M, Ali S, Rehman M Z U, et al. Science of the Total Environment, 2018, 631-632: 1175.
[2] Mortensen L H, Ronn R, Vestergard M. Ecotoxicology and Environmental Safety, 2018, 156: 452.
[3] Ettler V, Chren M, Mihaljevic M, et al. Geoderma, 2017, 299: 32.
[4] Segvic B, Girardclos S, Zanoni G, et al. Applied Clay Science, 2018, 160: 22.
[5] Xu W P, Zhu J M, Johnson T M, et al. Geochimica et Cosmochimica Acta, 2020, 272: 121.
[6] Fan C H, Du B, Zhang Y C, et al. Journal of Geochemical Exploration, 2017, 176: 50.
[7] ZHANG Gan-lin, LI De-cheng(张甘霖, 李德成). Manual of Soil Description and Sampling(野外土壤描述与采样手册). Beijing: Science Press(北京: 科学出版社), 2016.
[8] FAN Chun-hui, DU Bo, ZHANG Ying-chao, et al(范春辉, 杜 波, 张颖超, 等). Spectroscopy and Spectral Analysis(光谱学与光谱分析), 2016, 36(8): 2625.
[9] Adusei-Gyamfi J, Ouddane B, Rietveld L, et al. Water Research, 2019, 160: 130.
[10] Inglezakis V J, Fyrillas M M, Park J. Journal of Hazardous Materials, 2019, 367: 224.
[11] Neris J B, Luzardo F H M, Silva E G P D, et al. Chemical Engineering Journal, 2019, 357: 404.
[12] Syafiuddin A, Salmiati S, Jonbi J, et al. Journal of Environmental Management, 2018, 218: 59.
[13] Khosravi R, Moussavi G, Ghaneian M T, et al. Journal of Molecular Liquids, 2018, 256: 163.
[14] Kashiwabara T, Kubo S, Tanaka M, et al. Geochimica et Cosmochimica Acta, 2017, 204: 52.
