Chemical Speciation and Environmental Risk of Cd in Soil Stabilized with Alkali-modified Attapulgite

TAO Ling; TONG Yun-long; YU Fang-ke; YANG Wan-hui; WANG Yi-rong; WANG Li; REN Jun

doi:10.15898/j.cnki.11-2131/td.202108270108

Rock and Mineral Analysis > 2022 > 41(1): 109-119. > DOI: 10.15898/j.cnki.11-2131/td.202108270108

TAO Ling, TONG Yun-long, YU Fang-ke, YANG Wan-hui, WANG Yi-rong, WANG Li, REN Jun. 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

Citation:

PDF (4810 KB)

Chemical Speciation and Environmental Risk of Cd in Soil Stabilized with Alkali-modified Attapulgite

TAO Ling^1,2,3,,
TONG Yun-long^1,2,
YU Fang-ke⁴,
YANG Wan-hui^1,2,
WANG Yi-rong^1,2,
WANG Li^1,2,
REN Jun^1,2,3, ,

1.
Key Laboratory of Yellow River Water Environment in Gansu Province, Lanzhou Jiaotong University, Lanzhou 730070, China
2.
School of Environmental and Municipal Engineering, Lanzhou Jiaotong University, Lanzhou 730070, China
3.
Gansu Hanxing Environmental Protection Co., Ltd., Lanzhou 730070, China
4.
School of Environmental and Science Engineering, Shaanxi University of Science & Technology, Xi'an 710021, China

More Information

Received Date: August 26, 2021
Revised Date: November 09, 2021
Accepted Date: December 07, 2021
Published Date: January 27, 2022

Abstract

HIGHLIGHTS
(1) Attapulgite was selected as the raw material and NaOH as the modifier.

(2) The surface roughness and adsorption capacity of attapulgite were increased by NaOH modification. Alkali-modified attapulgite significantly improved the physical and chemical properties of soil, thus improving the stabilization effect on Cd.

(3) Alkali-modified attapulgite converted active exchangeable Cd into stable residual Cd in soil, and reduced the risk assessment code and potential risk index of Cd by one risk level, which significantly reduced the environmental risk of Cd.

ABSTRACT

BACKGROUNDHeavy metal pollution in soil has been a serious threat to human health and ecological environmental safety. Stabilization remediation has become an important means of remediation of heavy metal contaminated soil due to the high efficiency and low cost. Attapulgite modified by alkali with an improved performance, provides an important basis for its stabilization and remediation of heavy metal contaminated soil.
OBJECTIVESTo analyze the changes in physical and chemical properties of attapulgite before and after modification, and to study the effects of attapulgite modified by NaOH on the chemical speciation changes and environmental risks of Cd in contaminated soil, and to explore the stabilization effects of attapulgite modified by NaOH on Cd in the soil.
METHODSDifferent proportions of NaOH were used to modify attapulgite. The surface characteristics, crystal structure and functional groups of the materials were analyzed by scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy. Stabilization experiments were carried out on artificially prepared heavy metal Cd contaminated soil to study the effects of NaOH-modified attapulgite on the changes of chemical speciation of Cd and environmental risks in contaminated soil.
RESULTSBy adding the modified material with the mass ratio of NaOH to attapulgite of 1:2, the pH value of the soil was significantly increased by 0.85 units. The exchangeable Cd content decreased by 46.28% and the residual Cd content increased by 1.98 times. The risk assessment code (RAC) and potential risk index (PRI) of Cd in soil decreased the most from 36.70% and 207.90 to 20.08% and 86.40, respectively, which effectively reduced the transfer capacity and environmental risk of Cd in soil. According to SEM, XRD and FTIR analyses, after modification, the surface roughness of attapulgite increased, chemical bonds such as Si-O-Si bonds were opened, so active sites for adsorption of heavy metals increased. Attapulgite modified by alkali immobilized Cd mainly through adsorption, and the reaction of silanol and hydroxide with Cd²⁺ generated precipitate, so as to achieve the effect of stabilizing and repairing Cd contaminated soil.
CONCLUSIONSAlkali-modified attapulgite can effectively stabilize Cd in soil, which has a significant application prospect in remediation of heavy metal contaminated soil.
- attapulgite,
- alkali modification,
- cadmium,
- chemical speciations,
- environmental risk,
- scanning electron microscopy,
- X-ray diffraction,
- Fourier transform infrared spectroscopy

FullText(HTML)

References (43)

References

Chai L, Wang Y H, Wang X, et al. Pollution characteristics, spatial distributions, and source apportionment of heavy metals in cultivated soil in Lanzhou, China[J]. Ecological Indicators, 2021, 125: 107507. doi: 10.1016/j.ecolind.2021.107507

余涛, 蒋天宇, 刘旭, 等. 土壤重金属污染现状及检测分析技术研究进展[J]. 中国地质, 2021, 48(2): 460-476. https://www.cnki.com.cn/Article/CJFDTOTAL-DIZI202102009.htm

Yu T, Jiang T X, Liu X, et al. Research progress in current status of soil heavy metal pollution and analysis technology[J]. Geology in China, 2021, 48(2): 460-476. https://www.cnki.com.cn/Article/CJFDTOTAL-DIZI202102009.htm

Basan H, Sirin M, Gokbayrak E, et al. A case study on pollution and a human health risk assessment of heavy metals in agricultural soils around Sinop Province, Turkey[J]. Chemosphere, 2020, 241: 125015. doi: 10.1016/j.chemosphere.2019.125015

Huang B, Li Z W, Huang J Q, et al. Aging effect on the leaching behavior of heavy metals (Cu, Zn, and Cd) in red paddy soil[J]. Environmental Science and Pollution Research International, 2015, 22(15): 11467-11477. doi: 10.1007/s11356-015-4386-x

张静静, 朱爽阁, 朱利楠, 等. 不同钝化剂对微碱性土壤镉、镍形态及小麦吸收的影响[J]. 环境科学, 2020, 41(1): 460-468. https://www.cnki.com.cn/Article/CJFDTOTAL-HJKZ202001055.htm

Zhang J J, Zhu S G, Zhu L N, et al. Effects of different amendments on fractions and uptake by winter wheat in slightly alkaline soil contaminated by cadmium and nickel[J]. Environmental Science, 2020, 41(1): 460-468. https://www.cnki.com.cn/Article/CJFDTOTAL-HJKZ202001055.htm

杨国航, 李合莲, 李菊梅, 等. 污泥农用对碱性土壤重金属元素形态分布的影响[J]. 济南大学学报(自然科学版), 2018, 32(2): 124-133. https://www.cnki.com.cn/Article/CJFDTOTAL-SDJC201802008.htm

Yang G H, Li H L, Li J M, et al. Effect of agricultural application of sludge on forms of heavy metal elements in alkaline soil[J]. Journal of University of Jinan (Science and Technology), 2018, 32(2): 124-133. https://www.cnki.com.cn/Article/CJFDTOTAL-SDJC201802008.htm

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. https://www.cnki.com.cn/Article/CJFDTOTAL-TURA201902003.htm

Xing J F, Cang L, Ren J H. Remediation stability of in situ chemical immobilization of heavy metals contamin-ated soil: A review[J]. Soils, 2019, 51(2): 224-234. https://www.cnki.com.cn/Article/CJFDTOTAL-TURA201902003.htm

冉洪珍, 郭朝晖, 肖细元, 等. 改良剂连续施用对农田水稻Cd吸收的影响[J]. 中国环境科学, 2019, 39(3): 1117-1123. doi: 10.3969/j.issn.1000-6923.2019.03.027

Ran H Z, Guo Z H, Xiao X Y, et al. Effects of continuous application of soil amendments on cadmium availability in paddy soil and uptake by rice[J]. China Environmental Science, 2019, 39(3): 1117-1123. doi: 10.3969/j.issn.1000-6923.2019.03.027

安茂国, 赵庆玲, 谭现锋, 等. 化学还原-稳定化联合修复铬污染场地土壤的效果研究[J]. 岩矿测试, 2019, 38(2): 204-211. doi: 10.15898/j.cnki.11-2131/td.201806040068

An M G, Zhao Q L, Tan X F, et al. Research on the effect of chemical reduction-stabilization combined reme-diation of Cr contaminated soil[J]. Rock and Mineral Analysis, 2019, 38(2): 204-211. doi: 10.15898/j.cnki.11-2131/td.201806040068

Li M Y, Zhang J C, Yang X, et al. Responses of ammonia-oxidizing microorganisms to biochar and compost amendments of heavy metals-polluted soil[J]. Journal of Environmental Sciences, 2021, 102: 263-272. doi: 10.1016/j.jes.2020.09.029

Ren J, Dai L, Tao L. Stabilization of heavy metals in sewage sludge by attapulgite[J]. Journal of the Air and Waste Management Association, 2021, 71(3): 392-399. doi: 10.1080/10962247.2020.1843563

陶雪, 杨琥, 季荣, 等. 固定剂及其在重金属污染土壤修复中的应用[J]. 土壤, 2016, 48(1): 1-11. https://www.cnki.com.cn/Article/CJFDTOTAL-TURA201601001.htm

Tao X, Yang H, Ji R, et al. Stabilizers and their applications in remediation of heavy metal-contaminated soil[J]. Soils, 2016, 48(1): 1-11. https://www.cnki.com.cn/Article/CJFDTOTAL-TURA201601001.htm

赵廷伟, 李洪达, 周薇, 等. 施用凹凸棒石对Cd污染农田土壤养分的影响[J]. 农业环境科学学报, 2019, 38(10): 2313-2318. doi: 10.11654/jaes.2019-0783

Zhao T W, Li H D, Zhou W, et al. Effects of attapulgite application on soil nutrients in Cd-contaminated farmland[J]. Journal of Agro-Environment Science, 2019, 38(10): 2313-2318. doi: 10.11654/jaes.2019-0783

谭科艳, 刘晓端, 刘久臣, 等. 凹凸棒石用于修复铜锌镉重金属污染土壤的研究[J]. 岩矿测试, 2011, 30(4): 451-456. doi: 10.3969/j.issn.0254-5357.2011.04.012

Tan K Y, Liu X R, Liu J C, et al. Remediation experiments of attapulgite clay to heavy metal contaminated soil[J]. Rock and Mineral Analysis, 2011, 30(4): 451-456. doi: 10.3969/j.issn.0254-5357.2011.04.012

陈展祥, 陈传胜, 陈卫平, 等. 凹凸棒石及其改性材料对土壤镉生物有效性的影响与机制[J]. 环境科学, 2018, 39(10): 4744-4751. https://www.cnki.com.cn/Article/CJFDTOTAL-HJKZ201810042.htm

Chen Z X, Chen C S, Chen W P, et al. Effect and mechanism of attapulgite and its modified materials on bioavailability of cadmium in soil[J]. Environmental Science, 2018, 39(10): 4744-4751. https://www.cnki.com.cn/Article/CJFDTOTAL-HJKZ201810042.htm

陶玲, 杨欣, 颜子皓, 等. 酸活化坡缕石制备重金属钝化材料的研究[J]. 非金属矿, 2018, 41(1): 11-14. doi: 10.3969/j.issn.1000-8098.2018.01.004

Tao L, Yang X, Yan Z H, et al. Study on the function of passivant for heavy metals with palygorskite modified by acid[J]. Non-Metallic Mines, 2018, 41(1): 11-14. doi: 10.3969/j.issn.1000-8098.2018.01.004

王金明, 易发成. 改性凹凸棒石表征及其对模拟核素Cs⁺的吸附研究[J]. 非金属矿, 2006, 29(2): 53-55. https://www.cnki.com.cn/Article/CJFDTOTAL-FJSK200602018.htm

Wang J M, Yi F C. Study on characterization of modified attapulgite and its adsorption capacity on simulated nuclide Cs⁺[J]. Non-Metallic Mines, 2006, 29(2): 53-55. https://www.cnki.com.cn/Article/CJFDTOTAL-FJSK200602018.htm

余树荣, 张婷, 戴虎虎, 等. 凹凸棒石复合氧化钙脱硫剂脱除SO₂的试验研究[J]. 非金属矿, 2009, 32(6): 1-2, 19. doi: 10.3969/j.issn.1000-8098.2009.06.001

Yu S R, Zhang T, Dai H H, et al. Study on desulfurization of SO₂ by attapulgite/calcium oxide compound desulfuri-zation agent[J]. Non-Metallic Mines, 2009, 32(6): 1-2, 19. doi: 10.3969/j.issn.1000-8098.2009.06.001

任珺, 刘丽莉, 陶玲, 等. 甘肃地区凹凸棒石的矿物组成分析[J]. 硅酸盐通报, 2013, 32(11): 2362-2365. https://www.cnki.com.cn/Article/CJFDTOTAL-GSYT201311043.htm

Ren J, Liu L L, Tao L, et al. Mineral composition analysis of attapulgite from Gansu area[J]. Bulletin of the Chinese Ceramic Society, 2013, 32(11): 2362-2365. https://www.cnki.com.cn/Article/CJFDTOTAL-GSYT201311043.htm

Dai L, Ren J, Tao L, et al. Chemical speciation and phytoavailability of Cr, Ni, Zn and Cu in loess amended with attapulgite-stabilized sewage sludge[J]. Environmental Pollutants and Bioavailability, 2019, 31(1): 112-119. doi: 10.1080/26395940.2019.1588076

Nemati K, Bakar N K A, Abas M R, et al. Speciation of heavy metals by modified BCR sequential extraction procedure in different depths of sediments from Sungai Buloh, Selangor, Malaysia[J]. Journal of Hazardous Materials, 2011, 192(1): 402-410.

Xu X B, Hu X, Ding Z H, et al. Effects of copyrolysis of sludge with calcium carbonate and calcium hydrogen phosphate on chemical stability of carbon and release of toxic elements in the resultant biochars[J]. Chemosphere, 2017, 189: 76-85. doi: 10.1016/j.chemosphere.2017.09.021

Ke X, Gui S F, Huang H, et al. Ecological risk assessment and source identification for heavy metals in surface sediment from the Liaohe River protected area, China[J]. Chemosphere, 2017, 175: 473-481. doi: 10.1016/j.chemosphere.2017.02.029

Wang W B, Tian G Y, Zhang Z F, et al. A simple hydro-thermal approach to modify palygorskite for high-efficient adsorption of methylene blue and Cu(Ⅱ) ions[J]. Chemical Engineering Journal, 2015, 265: 228-238. doi: 10.1016/j.cej.2014.11.135

张平萍, 陈雪刚, 程继鹏, 等. 水热条件下坡缕石在NaOH溶液中的行为及结构变化[J]. 无机化学学报, 2009, 25(9): 1545-1550. doi: 10.3321/j.issn:1001-4861.2009.09.006

Zhang P P, Chen X G, Cheng J P, et al. Behavior and structural transformation of palygorskite in NaOH solution under hydrothermal conditions[J]. Chinese Jouranl of Inorganic Chemistry, 2009, 25(9): 1545-1550. doi: 10.3321/j.issn:1001-4861.2009.09.006

Suarez M, Garcia R E. FTIR spectroscopic study of palygorskite: Influence of the composition of the octahedral sheet[J]. Applied Clay Science, 2006, 31(1-2): 154-163. doi: 10.1016/j.clay.2005.10.005

Yan W C, Liu D, Tan D Y, et al. FTIR spectroscopy study of the structure changes of palygorskite under heating[J]. Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2012, 97: 1052-1057. doi: 10.1016/j.saa.2012.07.085

Suarez M, Garcia R E. Macroscopic palygorskite from lisbom volcanic complex[J]. European Journal of Mineralogy, 2006, 18(1): 119-126. doi: 10.1127/0935-1221/2006/0018-0119

辜娇峰, 周航, 吴玉俊, 等. 复合改良剂对稻田Cd、As活性与累积的协同调控[J]. 中国环境科学, 2016, 36(1): 206-214. doi: 10.3969/j.issn.1000-6923.2016.01.035

Gu J F, Zhou H, Wu Y J, et al. Synergistic control of combined amendment on bioavailability and accumulation of Cd and As in rice paddy soil[J]. China Environmental Science, 2016, 36(1): 206-214. doi: 10.3969/j.issn.1000-6923.2016.01.035

陶玲, 管天成, 刘瑞珍, 等. 热改性坡缕石对土壤Cd污染的钝化修复研究[J]. 农业环境科学学报, 2021, 40(4): 782-790. https://www.cnki.com.cn/Article/CJFDTOTAL-NHBH202104012.htm

Tao L, Guan T C, Liu R Z, et al. Stabilization remediation of cadmium contaminated soil by using heat-modified palygorskite[J]. Journal of Agro-Environment Science, 2021, 40(4): 782-790. https://www.cnki.com.cn/Article/CJFDTOTAL-NHBH202104012.htm

Yin X L, Xu Y M, Huang R, et al. Remediation mechanisms for Cd-contaminated soil using natural sepiolite at the field scale[J]. Environmental Science: Processes & Impacts, 2017, 19(12): 1563-1570.

廖启林, 刘聪, 朱伯万, 等. 凹凸棒石调控Cd污染土壤的作用及其效果[J]. 中国地质, 2014, 41(5): 1693-1704. doi: 10.3969/j.issn.1000-3657.2014.05.023

Liao Q L, Liu C, Zhu B W, et al. The role and effect of applying attapulgite to controlling Cd-contaminated soil[J]. Geology in China, 2014, 41(5): 1693-1704. doi: 10.3969/j.issn.1000-3657.2014.05.023

Qin F, Shan X Q, Wei B. Effects of low-molecular-weight organic acids and residence time on desorption of Cu, Cd, and Pb from soils[J]. Chemosphere, 2004, 57(4): 253-263. doi: 10.1016/j.chemosphere.2004.06.010

武成辉, 李亮, 晏波, 等. 新型硅酸盐钝化剂对镉污染土壤的钝化修复效应研究[J]. 农业环境科学学报, 2017, 36(10): 2007-2013. doi: 10.11654/jaes.2017-0471

Wu C H, Li L, Yan B, et al. Remediation effects of a new type of silicate passivator on cadmium-contaminated soil[J]. Journal of Agro-Environment Science, 2017, 36(10): 2007-2013. doi: 10.11654/jaes.2017-0471

王永昕, 孙约兵, 徐应明, 等. 施用鸡粪对海泡石钝化修复镉污染菜地土壤的强化效应及土壤酶活性影响[J]. 环境化学, 2016, 35(1): 159-169. https://www.cnki.com.cn/Article/CJFDTOTAL-HJHX201601020.htm

Wang Y X, Sun Y B, Xu Y M, et al. Enhancement of chicken manure on the immobilization remediation of cadmium contaminated vegetable soil and enzyme activity using sepiolite[J]. Environmental Chemistry, 2016, 35(1): 159-169. https://www.cnki.com.cn/Article/CJFDTOTAL-HJHX201601020.htm

Zotiadis V, Argyraki A, Theologou E. Pilot scale application of attapulgitic clay for stabilization of toxic elements in contaminated soil[J]. Journal of Geotechnical and Geoenvironmental Engineering, 2012, 138(5): 633-637. doi: 10.1061/(ASCE)GT.1943-5606.0000620

罗宁临, 李忠武, 黄梅, 等. 壳聚糖(改性)-沸石对农田土壤重金属镉钝化技术研究[J]. 湖南大学学报(自然科学版), 2020, 47(4): 132-140. https://www.cnki.com.cn/Article/CJFDTOTAL-HNDX202004017.htm

Luo N L, Li Z W, Huang M, et al. Immobilizing cadmium in paddy soil by using modified chitosan-zeolite[J]. Journal of Hunan University (Natural Sciences), 2020, 47(4): 132-140. https://www.cnki.com.cn/Article/CJFDTOTAL-HNDX202004017.htm

Shi L, Guo Z H, Peng C, et al. Immobilization of cadmium and improvement of bacterial community in contaminated soil following a continuous amendment with lime mixed with fertilizers: A four-season field experiment[J]. Ecotoxicology and Environmental Safety, 2019, 171: 425-434. doi: 10.1016/j.ecoenv.2019.01.006

Zhao B W, Xu R Z, Ma F F, et al. Effects of biochars derived from chicken manure and rape straw on speciation and phytoavailability of Cd to maize in artificially contaminated loess soil[J]. Journal of Environmental Management, 2016, 184(3): 569-574.

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

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

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. https://www.cnki.com.cn/Article/CJFDTOTAL-TURA202003002.htm

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. https://www.cnki.com.cn/Article/CJFDTOTAL-TURA202003002.htm

郭炜辰, 杜立宇, 梁成华, 等. 天然与改性沸石对土壤Cd污染赋存形态的影响研究[J]. 土壤通报, 2019, 50(3): 719-724. https://www.cnki.com.cn/Article/CJFDTOTAL-TRTB201903030.htm

Guo W C, Du L Y, Liang C H, et al. Effects of natural and ammonium chloride/calcium chloride-modified zeolites on cadmium speciation in cintaminated soil[J]. Chinese Journal of Soil Science, 2019, 50(3): 719-724. https://www.cnki.com.cn/Article/CJFDTOTAL-TRTB201903030.htm

迟荪琳, 徐卫红, 熊仕娟, 等. 不同镉水平下纳米沸石对土壤pH、CEC及Cd形态的影响[J]. 环境科学, 2017, 38(4): 1654-1666. https://www.cnki.com.cn/Article/CJFDTOTAL-HJKZ201704049.htm

Chi S L, Xu W H, Xiong S J, et al. Effects of nano zelites on pH, CEC in soil and Cd fractions in plant and soil at different cadmium levels[J]. Environmental Science, 2017, 38(4): 1654-1666. https://www.cnki.com.cn/Article/CJFDTOTAL-HJKZ201704049.htm

Supplements (0)

Cited By