Characteristics and Effects of Modified Attapulgite for Stabilization of Cadmium Contaminated Alkaline Soils
-
摘要:
凹凸棒及其改性材料具有较发达的比表面积、丰富的官能团及较强的吸附能力，被作为良好的环境修复材料而成为农田土壤重金属修复领域的研究热点。目前中国农田土壤Cd污染现状仍然严峻，为探究改性凹凸棒的钝化机制及其对碱性土壤Cd污染的钝化效果，本文采用氢氧化钠、氯化铁两种改性剂对凹凸棒改性，利用扫描电镜（SEM）、X射线衍射（XRD）、傅里叶红外光谱（FTIR）及比表面积测定（BET）和孔径分析（BJH）对改性前后凹凸棒的微观结构和表面形态进行表征，结合表征结果分析其钝化机理，开展室内模拟Cd污染碱性土壤培养试验、生菜盆栽试验，采用原子吸收分光光度法测定土壤Cd含量，探究单一施用与复配施用两种改性凹凸棒对碱性土壤Cd的钝化效果差异。结果表明：碱处理后凹凸棒Si—O基团、结构负电荷增多，铁改性后凹凸棒微孔数量增多、比表面积增大，两种改性方法均使凹凸棒的内部结构及表面形态发生明显改变，吸附能力得以提升。碱改性凹凸棒（AM）通过更强的化学吸附能力实现对Cd的钝化，可提高土壤pH和阳离子交换量（CEC），而铁改性凹凸棒（IM）则具有更强的物理吸附能力和较强的化学吸附能力，使得土壤pH降低、CEC升高，两种材料复配施用能够在一定程度上减小了pH升高幅度、提高土壤CEC值，提高钝化效果。碱、铁改性凹凸棒按质量配比3：1、土壤质量的2.00%施用后，土壤Cd有效态含量可降低33.85%，生菜对Cd的富集系数降低24.49%，在各处理组中效果最好。因此，铁改性凹凸棒对碱性土壤重金属Cd具有良好的钝化效果。在实际应用中应避免单独施用碱改性凹凸棒，可考虑与其他钝化材料复配施用，实现在保护土壤质量的同时更好地降低土壤Cd污染。
Abstract:BACKGROUND With the high specific surface area, rich functional groups and strong adsorption capacity, attapulgite (AT) and its modified materials have become a research hotspot in the field of heavy metal remediation of farmland soil.
OBJECTIVES To investigate the stabilization mechanism and effect of different modified AT for Cd-contaminated alkaline soil.
METHODS AT materials were modified by sodium hydroxide and ferric chloride. Scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared (FTIR), and nitrogen adsorption/desorption test (BET-BJH) were used to analyze the microstructure and surface morphology of the modified AT. Combined with the characterization results, the passivation mechanism was analyzed, and the indoor simulated Cd-contaminated alkaline soil cultivation experiment and the lettuce potting experiment were carried out. Soil Cd content was determined by atomic absorption spectrophotometry. The effect differences between single application and compound application of two modified attapulgites in Cd-contaminated alkaline soil were investigated.
RESULTS Alkali treatment made the Si-O groups and structural negative charges increase, and the number of micropores and specific surface area of the iron-modified attapulgite (IM) also increased. The internal pore distribution and surface morphology of attapulgite can be significantly changed in two types of modification, which can also improve their adsorption capacity. Alkali-modified attapulgite (AM) can improve soil pH and cation exchange (CEC) by stronger chemical adsorption capacity, while IM has stronger physical adsorption capacity and strong chemical adsorption capacity, which makes soil pH decrease and CEC rise. To a certain extent, the compound application of the two materials can reduce soil pH and improve CEC, which can improve their stabilization effect. After using the passivation material of AM: IM ratio of 3:1 and 2.00% of the soil mass, the available DTPA-Cd content was reduced by 33.85%, and the BCF of lettuce was reduced by 24.49%. The treatment attained the best stabilization effect.
CONCLUSIONS IM has good stabilization effect on heavy metal Cd in alkaline soil. AM should be avoided for single application, and it can be recombined with other stabilization materials to achieve better reduction of soil Cd pollution while improving the quality of alkali soil.
-
-
表 1 凹凸棒的比表面积和孔体积变化
Table 1. Change in attapulgite properties including BET specific surface area (SBET), and total pore volume (Vpores)
样品材料 孔体积
(cm3/g)平均孔径
(nm)平均粒径
(nm)BET比表面积
(m2/g)凹凸棒原土(AT) 0.08785 4.92 84.02 71.41 碱改性凹凸棒(AM) 0.08573 5.65 98.93 60.65 铁改性凹凸棒(IM) 0.1213 4.65 57.57 104.22 
下载: 导出CSV
-
[1] Wan X M, Yang J X, Song W. Pollution status of agricultural land in China: Impact of land use and geographical position[J]. Soil & Water Research, 2018, 13(4): 234-242.
[2] 武超, 周顺江, 王华利, 等. 生物炭和锌对土壤镉赋存形态及小麦镉积累的影响[J]. 环境科学研究, 2022, 35(1): 202-210. doi: 10.13198/j.issn.1001-6929.2021.10.15
Wu C, Zhou S J, Wang H L, et al. Effects of biochar and zinc on soil cadmium fractions and wheat accumulation[J]. Research of Environmental Sciences, 2022, 35(1): 202-210. doi: 10.13198/j.issn.1001-6929.2021.10.15
[3] Wang P, Chen H, Kopittke P M, et al. Cadmium contamination in agricultural soils of China and the impact on food safety[J]. Environmental Pollution, 2019, 249: 1038-1048. doi: 10.1016/j.envpol.2019.03.063
[4] 王进进, 杨行健, 胡峥, 等. 基于风险等级的重金属污染耕地土壤修复技术集成体系研究[J]. 农业环境科学学报, 2019, 38(2): 249-256. https://www.cnki.com.cn/Article/CJFDTOTAL-NHBH201902002.htm
Wang J J, Yang X J, Hu Z, et al. Research on the risk level-based technology integration for the remediation of heavy metals polluted farmland[J]. Journal of Agricultural Environment Science, 2019, 38(2): 249-256. https://www.cnki.com.cn/Article/CJFDTOTAL-NHBH201902002.htm
[5] 杨京民, Bonheur G. 镉、砷复合污染土壤钝化修复研究进展[J]. 环境污染与防治, 2021, 43(9): 1189-1195, 1200. doi: 10.15985/j.cnki.1001-3865.2021.09.019
Yang J M, Bonheur G, et al. The immobilization remediation of cadmium and arsenic combined contaminated soils: A review[J]. Environmental Pollution and Control, 2021, 43(9): 1189-1195, 1200. doi: 10.15985/j.cnki.1001-3865.2021.09.019
[6] 邢金峰, 仓龙, 任静华. 重金属污染农田土壤化学钝化修复的稳定性研究进展[J]. 土壤, 2019, 51(2): 224-234. doi: 10.13758/j.cnki.tr.2019.02.003
Xing J F, Cang L, Ren J H. Remediation stability of in situ chemical immobilization of heavy metals contaminated soil: A review[J]. Soils, 2019, 51(2): 224-234. doi: 10.13758/j.cnki.tr.2019.02.003
[7] 陈怀满. 环境土壤学[M]. 北京: 科学出版社, 2005: 397-412.
Chen H M. Environmental soil science[M]. Beijing: Science Press, 2005: 397-412.
[8] 谢玉峰, 刘迪, 陈振宁, 等. 耕地土壤重金属污染钝化修复技术研究进展[J]. 江苏农业科学, 2020, 48(18): 30-36. doi: 10.15889/j.issn.1002-1302.2020.18.006
Xie Y F, Liu D, Chen Z N, et al. Research progress on passivation remediation technology of heavy metal pollution in cultivated soil[J]. Jiangsu Agricultural Sciences, 2020, 48(18): 30-36. doi: 10.15889/j.issn.1002-1302.2020.18.006
[9] 陈哲, 冯秀娟, 朱易春, 等. 天然及改性凹凸棒对稀土尾矿土壤中重金属铅的钝化效果研究[J]. 岩矿测试, 2020, 39(6): 847-855. doi: 10.15898/j.cnki.11-2131/td.202006250096 http://www.ykcs.ac.cn/cn/article/doi/10.15898/j.cnki.11-2131/td.202006250096
Chen Z, Feng X J, Zhu Y C, et al. Study on the passivation effect of natural and modified attapulgite on heavy metal lead in soils of the rare earth tailings[J]. Rock and Mineral Analysis, 2020, 39(6): 847-855. doi: 10.15898/j.cnki.11-2131/td.202006250096 http://www.ykcs.ac.cn/cn/article/doi/10.15898/j.cnki.11-2131/td.202006250096
[10] Xu Y, Liang X, Xu Y, et al. Remediation of heavy metal-polluted agricultural soils using clay minerals: A review[J]. Pedosphere, 2017, 27(2): 193-204. doi: 10.1016/S1002-0160(17)60310-2
[11] 朱维, 刘代欢, 陈建清, 等. 黏土矿物在土壤重金属污染中的应用研究进展[J]. 土壤通报, 2018, 49(2): 499-504. doi: 10.19336/j.cnki.trtb.2018.02.34
Zhu W, Liu D H, Chen J Q, et al. Research progress on the application of clay minerals in the remediation of cadmium polluted farmland[J]. Chinese Journal of Soil Science, 2018, 49(2): 499-504. doi: 10.19336/j.cnki.trtb.2018.02.34
[12] 谢晶晶, 陈天虎, 刘海波, 等. 苏皖地区凹凸棒石黏土的特征和应用发展方向[J]. 硅酸盐学报, 2018, 46(5): 746-754. doi: 10.14062/j.issn.0454-5648.2018.05.20
Xie J J, Chen T H, Liu H B, et al. Development and application of palygorskite clays from Jiangsu and Anhui Provinces[J]. Journal of the Chinese Ceramic Society, 2018, 46(5): 746-754. doi: 10.14062/j.issn.0454-5648.2018.05.20
[13] Wang W B, Wang F F, Kang Y R, et al. Enhanced adsorptive removal of methylene blue from aqueous solution by alkali-activated palygorskite[J]. Water, Air & Soil Pollution, 2015, 226(3): 1-13.
[14] 陶玲, 仝云龙, 余方可, 等. 碱改性凹凸棒石对土壤中镉化学形态及环境风险的影响[J]. 岩矿测试, 2022, 41(1): 109-119. doi: 10.15898/j.cnki.11-2131/td.202108270108 http://www.ykcs.ac.cn/cn/article/doi/10.15898/j.cnki.11-2131/td.202108270108
Tao L, Tong Y L, Yu F K, et al. Chemical speciation and environmental risk of Cd in soil stabilized with alkali-modified attapulgite[J]. Rock and Mineral Analysis, 2022, 41(1): 109-119. doi: 10.15898/j.cnki.11-2131/td.202108270108 http://www.ykcs.ac.cn/cn/article/doi/10.15898/j.cnki.11-2131/td.202108270108
[15] 刘爱平, 黄阳, 王维清, 等. 铁改性凹凸棒土对Sb(Ⅴ)的吸附研究[J]. 非金属矿, 2018, 41(6): 26-29. doi: 10.3969/j.issn.1000-8098.2018.06.008
Liu A P, Huang Y, Wang W Q, et al. Study on the adsorption of Sb(Ⅴ) by iron modified attapulgite[J]. Non-Metallic Mines, 2018, 41(6): 26-29. doi: 10.3969/j.issn.1000-8098.2018.06.008
[16] 耿健, 杨盼, 唐婉莹. 铁改性热处理凹凸棒颗粒对水体磷的去除效果[J]. 环境工程, 2020, 38(10): 114-119. doi: 10.11835/j.issn.1000-582X.2019.267
Geng J, Yang P, Tang W Y. Phosphorus removal by the iron modified thermally treated granular attapulgite clay[J]. Environmental Engineering, 2020, 38(10): 114-119. doi: 10.11835/j.issn.1000-582X.2019.267
[17] 窦韦强, 安毅, 秦莉, 等. 稻米镉的生物富集系数与其影响因素的量化关系[J]. 土壤, 2021, 53(4): 788-793. doi: 10.13758/j.cnki.tr.2021.04.016
Dou W Q, An Y, Qin L, et al. Quantitative relationship between the bioconcentration factor of rice cadmium and its influencing factors[J]. Soils, 2021, 53(4): 788-793. doi: 10.13758/j.cnki.tr.2021.04.016
[18] 朱永峰, 宗莉, 于惠, 等. 凹凸棒石基新型水处理吸附材料研究进展[J]. 硅酸盐通报, 2020, 39(7): 2308-2320. doi: 10.16552/j.cnki.issn1001-1625.2020.07.040
Zhu Y F, Zong L, Yu H, et al. Research progress of the novel adsorbent for water treatment based on attapulgite[J]. Bulletin of the Chinese Ceramic Society, 2020, 39(7): 2308-2320. doi: 10.16552/j.cnki.issn1001-1625.2020.07.040
[19] White R D, Bavykin D V, Walsh F C. The stability of halloysite nanotubes in acidic and alkaline aqueous suspensions[J]. Nanotechnology, 2012, 23(6): 65705-65715. doi: 10.1088/0957-4484/23/6/065705
[20] Wei X Y, Sun Y L, Pan D Q, et al. Adsorption properties of Na-palygorskite for Cs sequestration: Effect of pH, ionic strength, humic acid and temperature[J]. Applied Clay Science, 2019, 183: 105363. doi: 10.1016/j.clay.2019.105363
[21] Wang Q, Wen J, Hu X H, et al. Immobilization of Cr(Ⅵ) contaminated soil using green-tea impregnated attapulgite[J]. Journal of Cleaner Production, 2021, 278: 123967. doi: 10.1016/j.jclepro.2020.123967
[22] Wan S L, Li Y, Cheng S, et al. Cadmium removal by FeOOH nanoparticles accommodated in biochar: Effect of the negatively charged functional groups in host[J]. Journal of Hazardous Materials, 2022, 421: 126807. doi: 10.1016/j.jhazmat.2021.126807
[23] Bardestani R, Patience G S, Kaliaguine S. Experimental methods in chemical engineering: Specific surface area and pore size distribution measurements—BET, BJH and DFT[J]. Canadian Journal of Chemical Engineering, 2019, 97: 2781-2791. doi: 10.1002/cjce.23632
[24] 闫和平, 杨甫, 段中会, 等. 黄陇煤田转角勘查区煤的微观孔隙结构特征及其影响因素[J]. 中国煤炭地质, 2022, 34(1): 18-25, 44. https://www.cnki.com.cn/Article/CJFDTOTAL-ZGMT202201004.htm
Yan H P, Yang F, Duan Z H, et al. Microscopic pore structure characteristics coal microscopic pore geometry features and its impact factors in Zhuanjiao exploration area, Huanglong Coalfield[J]. Coal Geology of China, 2022, 34(1): 18-25, 44. https://www.cnki.com.cn/Article/CJFDTOTAL-ZGMT202201004.htm
[25] 王超勇, 鲍园, 琚宜文. 利用FE-SEM、HIP、N2吸附实验表征生物气化煤系有机岩储层微观孔隙结构演化[J]. 地球科学, 2020, 45(1): 251-262. https://www.cnki.com.cn/Article/CJFDTOTAL-DQKX202001020.htm
Wang C Y, Bao Y, Ju Y W. Micropore structure evolution of organic matters in coal measures due to bioconversion using FE-SEM, HIP and N2 adsorption experiments[J]. Earth Science, 2020, 45(1): 251-262. https://www.cnki.com.cn/Article/CJFDTOTAL-DQKX202001020.htm
[26] Boudriche L, Chamayou A, Calvet R, et al. Influence of different dry milling processes on the properties of an attapulgite clay, contribution of inverse gas chromatography[J]. Powder Technology, 2014, 254: 352-363. doi: 10.1016/j.powtec.2014.01.041
[27] 丁守一, 黄亚继, 陈浩, 等. CuCl2改性磁性凹凸棒土的脱汞性能[J]. 化工进展, 2020, 39(3): 1187-1195. https://www.cnki.com.cn/Article/CJFDTOTAL-HGJZ202003045.htm
Ding S Y, Huang Y J, Chen H, et al. Mercury removal performance of CuCl2-modified magnetic attapulgite[J]. Chemical Industry and Engineering Progress, 2020, 39(3): 1187-1195. https://www.cnki.com.cn/Article/CJFDTOTAL-HGJZ202003045.htm
[28] Kragović M, Daković A, Marković M, et al. Characterization of lead sorption by the natural and Fe(Ⅲ)-modified zeolite[J]. Applied Surface Science, 2013, 283(1): 764-774.
[29] Lu H L, Li K W, Nkoh J, et al. Effects of pH variations caused by redox reactions and pH buffering capacity on Cd(Ⅱ) speciation in paddy soils during submerging/draining alternation[J]. Ecotoxicology and Environmental Safety, 2022, 234: 113409. doi: 10.1016/j.ecoenv.2022.113409
[30] 赵维俊, 敬文茂, 马剑, 等. 祁连山哈溪林区典型植被土壤阳离子交换量和交换性盐基离子的变化特征[J]. 中国水土保持, 2019(11): 17-20. doi: 10.3969/j.issn.1000-0941.2019.11.008
Zhao W J, Jing W M, Ma J, et al. Variation characteristics of soil cation exchange capacity and exchangeable base cations of typical vegetation in Haxi forest region of Qilian Mountains[J]. Soil and Water Conservation in China, 2019(11): 17-20. doi: 10.3969/j.issn.1000-0941.2019.11.008
[31] 窦韦强, 安毅, 秦莉, 等. 土壤pH对镉形态影响的研究进展[J]. 土壤, 2020, 52(3): 439-444. doi: 10.13758/j.cnki.tr.2020.03.002
Dou W Q, An Y, Qin L, et al. Advances in effects of soil pH on cadmium form[J]. Soils, 2020, 52(3): 439-444. doi: 10.13758/j.cnki.tr.2020.03.002
[32] 雍莹莹, 徐应明, 黄青青, 等. 巯基坡缕石-硫酸锰复配对碱性土壤镉污染钝化阻控效应[J]. 农业环境科学学报, 2021, 40(12): 2681-2692. doi: 10.11654/jaes.2021-0426
Yong Y Y, Xu Y M, Huang Q Q, et al. Immobilization effect of mercaptopalygorskite and manganese sulfate on Cd pollution in alkaline soil[J]. Journal of Agro-Environment Science, 2021, 40(12): 2681-2692. doi: 10.11654/jaes.2021-0426
-
图(7)
表(1)
计量
- 文章访问数: 1708
- PDF下载数: 22
- 施引文献: 0