Divergent Aging Mechanisms of Calcium ArsenicResidue under Dry-Wet and Freeze-Thaw Cycles: Toxic Metal Mobility, MultiscalePhysicochemical Characterization, and Escalated Ecological Risks

Abstract

This study investigates the long-term mobilityand ecological risks of As, Zn, and Cd in calcium arsenic residue (CAR) undersimulated dry-wet (DW) and freeze-thaw (FT) cycles. Accelerated agingexperiments, combined with multiscale characterization (XRD, XPS, SEM, FTIR),revealed distinct transformation mechanisms. DW cycles promotedcarbonate-driven dissolution, As(III) oxidation to As(V) (resulting in an 18.4%increase in As(V) as shown by XPS), and sulfide oxidation (with reductions of47.7% in ZnS and 15.08% in CdS). These processes increased the acid-solublemetal fractions (F1: As by 11.3%, Zn by 6.0%, and Cd by 8.7%) and metal releaserates (52.39% for As, 42.63% for Zn, and 68.55% for Cd under DW conditions). Incontrast, FT cycles induced mechanical fracturing and ice-mediatedstabilization, which limited ion migration, partially amorphized ZnO, andpromoted the precipitation of Cd(OH)₂. Ecological risk assessmentsindicated rising risks, with integrated potential ecological risk indices(IPER) reaching 11,187.85 under DW conditions and 10,668.29 under FTconditions, with arsenic contributing over 80%. The Risk Assessment Code (RAC)reclassified all metals into moderate-risk categories (As: 11.9-19.7%, Zn:9.4-15.2%, Cd: 12.1-18.6%). Weibull modeling (α = 6.98-10.98, R² > 0.96) described the nonlinear kinetics, showing that cadmium aged thefastest (λ: Cd > As > Zn), with delayed but persistent risks under FTconditions. These results underscore the importance of developingclimate-resilient stabilization strategies. The integrated framework combiningmineral evolution, kinetics, and risk forecasting offers significant insightsfor managing legacy CAR pollution under changing climate conditions.

Keywords

Calcium arsenic residue / Dry-wet cycles / Freeze-thaw cycles / Heavy metal / Ecological risk assessment

Supplementary Materials

The following supporting information can be found at: https://www.sciepublish.com/article/pii/720, Figure S1: The impacts of DW and FT on CAR particle size distribution and cumulative curves: (a,d) raw sample; (b,e) DW; (c,f) FT; Figure S2: Variations in the concentrations of bioavailable As, Zn, and Cd in CAR after 1 to 28 cycles of DW and FT cycling; Figure S3: Exponential model of heavy metals in CAR under accelerated aging conditions for 28 years, subjected to DW and FT cycles. DW: (a) As, (b) Zn, (c) Cd; FT: (d) As, (e) Zn, (f) Cd; Table S1: Major elemental composition of CAR; Table S2: Toxicity impact factors in the Potential Ecological Risk Index (IPER) methodology; Table S3: Risk level evaluation of heavy metal pollution by Eri {E}_{r}^{i} Eri​ and I_PER; Table S4: Potential Ecological Risk Values of CAR after DW and FT Cycles.

Author Contributions

X.Z.: Conceptualization, Methodology, Software, Investigation, Writing—Original Draft. G.W.: Methodology, Data Curation. Y.D.: Supervision, Data Curation, Formal analysis. Z.Z.: Writing—Review & Editing, Validation, M.R.: Writing—Review & Editing. D.D.: Visualization, Writing—Review & Editing, Supervision, Data Curation.

Ethics Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

The authors confirm that the data supporting the findings of this study are available within the article or its supplementary materials.

Funding

This research was supported by the major innovation projects of Hubei province of China (Project No. 2019ACA156).

Declaration of Competing Interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

References

[1] Du Y, Du Y, Ma W, Zhao X, Ma M, Cao L, et al. Application of dirty-acid wastewater treatment technology in non-ferrous metal smelting industry: Retrospect and prospect. J. Environ. Manag. 2024, 352, 120050.

[2] Liao T, Xi Y, Zhang L, Li J, Cui K. Removal of toxic arsenic (As (III)) from industrial wastewater by ultrasonic enhanced zero-valent lead combined with CuSO₄. J. Hazard. Mater. 2021, 408, 124464.

[3] Wang J, Chen C. The current status of heavy metal pollution and treatment technology development in China. Environ. Technol. Rev. 2015, 4, 39-53.

[4] Wang J, Liu J, Peng X, He M, Hu X, Zhao J, et al. Reductive removal of As (V) and As (III) from aqueous solution by the UV/sulfite process: Recovery of elemental arsenic. Water Res. 2022, 223, 118981.

[5] Du Y, Zhao X, Xu Y, Ma W, Wang G, Zhao Z, et al. Innovative hydrogen sulfide generation from natural pyrrhotite: A green solution for acid wastewater treatment with resource recovery benefits. Process Saf. Environ. Prot. 2024, 194, 96-106.

[6] Xu L, Zheng Y, Zhao Y, Chen W. Recovery of arsenic oxide, harmless gypsum residue and clean water by lime neutralization and precipitation. Hydrometallurgy 2023, 215, 105996.

[7] Tenodi KZ, Tenodi S, Nikić J, Mohora E, Agbaba J, Rončević S. Optimizing arsenic removal from groundwater using continuous flow electrocoagulation with iron and aluminum electrodes: An experimental and modeling approach. J. Water Process Eng. 2024, 66, 106082.

[8] Nguyen DA, Nguyen DV, Jeong G, Asghar N, Jang A. Critical evaluation of hybrid metal–organic framework composites for efficient treatment of arsenic–contaminated solutions by adsorption and membrane–separation process. Chem. Eng. J. 2023, 461, 141789.

[9] Maity JP, Chen CY, Bhattacharya P, Sharma RK, Ahmad A, Patnaik S, et al. Advanced application of nano-technological and biological processes as well as mitigation options for arsenic removal. J. Hazard. Mater. 2021, 405, 123885.

[10] Jiang H, Zheng J, Fu Y, Wang Z, Yilmaz E, Cui L. Slag-based stabilization/solidification of hazardous arsenic-bearing tailings as cemented paste backfill: Strength and arsenic immobilization assessment. Case Stud. Constr. Mater. 2024, 20, e03002.

[11] Rahidul Hassan H. A review on different arsenic removal techniques used for decontamination of drinking water. Environ. Pollut. Bioavailab. 2023, 35, 2165964.

[12] Bhowmik T, Sarkar S, Bhattacharya A, Mukherjee A. A review of arsenic mitigation strategies in community water supplies with insights from South Asia: Options, opportunities and constraints. Environ. Sci. Water Res. Technol. 2022, 8, 2491-2520.

[13] Chu T, Zhang Y, Kong L, Li K, Zhao Z, Xu L, et al. Controllable H₂S supply via membrane contactors for safe and efficient arsenic precipitation from acidic wastewater. J. Hazard. Mater. 2024, 480, 136251.

[14] Zhao X, Ma M, Du Y, Ma W, Wang G, Du D. Mineralogical insights into anion and cation dissolution behavior in calcium arsenic residue from copper smelting: Implications for safe disposal. J. Environ. Chem. Eng. 2024, 12, 113407.

[15] Ma X, Yuan Z, Zhang G, Zhang J, Wang X, Wang S, et al. Alternative Method for the Treatment of Hydrometallurgical Arsenic–Calcium Residues: The Immobilization of Arsenic as Scorodite. ACS Omega 2020, 5, 12979-12988.

[16] Wang X, Wang L, Chen J. Stabilization/solidification of metallurgical solid wastes. In Low Carbon Stabilization and Solidification of Hazardous Wastes; Elsevier: Amsterdam, The Netherlands, 2022; pp. 243–257.

[17] Khatun J, Intekhab A, Dhak DJT. Effect of uncontrolled fertilization and heavy metal toxicity associated with arsenic (As), lead (Pb) and cadmium (Cd), and possible remediation. Toxicology 2022, 477, 153274.

[18] Lv H, Ji C, Ding J, Yu L, Cai H. High levels of zinc affect nitrogen and phosphorus transformation in rice rhizosphere soil by modifying microbial communities. Plants 2022, 11, 2271.

[19] Martínez-Villegas N, Briones-Gallardo R, Ramos-Leal JA, Avalos-Borja M, Castañón-Sandoval AD, Razo-Flores E, et al. Arsenic mobility controlled by solid calcium arsenates: A case study in Mexico showcasing a potentially widespread environmental problem. Environ. Pollut. 2013, 176, 114-122.

[20] Chakraborti D, Rahman MM, Mukherjee A, Alauddin M, Hassan M, Dutta RN, et al. Groundwater arsenic contamination in Bangladesh—21 Years of research. J. Trace Elem. Med. Biol. 2015, 31, 237-248.

[21] Uddin R, Huda N. Arsenic Poisoning in Bangladesh. Oman Med. J. 2011, 26, 207.

[22] Fei J, Ma J, Yang J, Liang Y, Ke Y, Yao L, et al. Effect of simulated acid rain on stability of arsenic calcium residue in residue field. Environ. Geochem. Health 2020, 42, 769-780.

[23] Zhang D, Wang S, Wang Y, Gomez MA, Jia Y. The long-term stability of calcium arsenates: Implications for phase transformation and arsenic mobilization. J. Environ. Sci. 2019, 84, 29-41.

[24] Mahandra H, Wu C, Ghahreman A. Leaching characteristics and stability assessment of sequestered arsenic in flue dust based glass. Chemosphere 2021, 276, 130173.

[25] Wang YY, He ZT, Tang JY, Sun Z, Xu H, Du J, et al. Long-term environmental stability and heavy metals release mechanism of desulfurized gypsum sludge from copper smelter. J. Cent. South Univ. (Sci. Technol.) 2023, 54, 562-576.

[26] Naisse C, Girardin C, Lefevre R, Pozzi A, Maas R, Stark A, et al. Effect of physical weathering on the carbon sequestration potential of biochars and hydrochars in soil. Gcb Bioenergy 2014, 7, 488-496.

[27] Bing H, He P, Zhang Y. Cyclic freeze–thaw as a mechanism for water and salt migration in soil. Environ. Earth Sci. 2015, 74, 675-681.

[28] Khan YK, Shah MH. Sequential extraction of selected metals to assess their mobility, pollution status and health risk in roadside soil. Environ. Monit. Assess. 2023, 195, 552.

[29] Zhang Z, Cai W, Hu Y, Yang K, Zheng Y, Fang C, et al. Ecological Risk Assessment and Influencing Factors of Heavy-Metal Leaching from Coal-Based Solid Waste Fly Ash. Front. Chem. 2022, 10, 932133.

[30] Hakanson L. An ecological risk index for aquatic pollution control. A sedimentological approach. Water Res. 1980, 14, 975-1001.

[31] Xiang M, Li Y, Yang J, Lei K, Li Y, Li F. Heavy metal contamination risk assessment and correlation analysis of heavy metal contents in soil and crops. Environ. Pollut. 2021, 278, 116911.

[32] Du M, Liu H, Hu D, Huang J, Liu Z, Fang Y. The leaching mechanism of heavy metals (Ni, Cd, As) in a gasification slag during acidification. Waste Manag. 2020, 114, 17-24.

[33] Verma A, Yadav S. Chemical Speciation and Risk Assessment of Metals in Surface Dust and Top Soil Samples Collected from Bhiwadi Industrial Cluster (BIC), Rajasthan, India. In AGU Fall Meeting Abstracts; vol. 2021, pp. B45M-1785. 2021.

[34] Li W, Sun Y, Huang Y, Shimaoka T, Wang H, Wang YN, et al. Evaluation of chemical speciation and environmental risk levels of heavy metals during varied acid corrosion conditions for raw and solidified/stabilized MSWI fly ash. Waste Manag. 2019, 87, 407-416.

[35] Shen Z, Hou D, Xu W, Zhang J, Jin F, Zhao B, et al. Assessing long-term stability of cadmium and lead in a soil washing residue amended with MgO-based binders using quantitative accelerated ageing. Sci. Total Environ. 2018, 643, 1571-1578.

[36] Wang L, Li X, Tsang DC, Jin F, Hou D. Green remediation of Cd and Hg contaminated soil using humic acid modified montmorillonite: Immobilization performance under accelerated ageing conditions. J. Hazard. Mater. 2020, 387, 122005.

[37] Zhang Y, Liu X, Li P, Xiao L, Zhou S, Wang X. Critical factors in soil organic carbon mineralization induced by drying, wetting and wet-dry cycles in a typical watershed of Loess Plateau. J. Environ. Manag. 2024, 362, 121313.

[38] Yang Z, Wang Y, Li X, Ren S, Xu H, Chang J. The effect of long-term freeze-thaw cycles on the stabilization of lead in compound solidified/stabilized lead-contaminated soil. Environ. Sci. Pollut. Res. 2021, 28, 37413-37423.

[39] Safa M, Goodarzi AR, Lorestani B. Enhanced post freeze-thaw stability of Zn/Pb co-contaminated soil through MgO-activated steel slag and fiber treatment. Cold Reg. Sci. Technol. 2023, 210, 103826.

[40] He Z, Zhang R, Sha A, Zuo Q, Xu Z, Wu M, et al. Anti-swelling mechanism of DMDACC on weathered crust elution-deposited rare earth ore. J. Rare Earths 2022, 40, 1803-1811.

[41] Zhao J, Li S. Study on processability, compressive strength, drying shrinkage and evolution mechanisms of microstructures of alkali-activated slag-glass powder cementitious material. Constr. Build. Mater. 2022, 344, 128196.

[42] Wang Z, Shui Z, Sun T, Li H, Chi H, Ouyang G, et al. Effect of MgO and superfine slag modification on the carbonation resistance of phosphogypsum-based cementitious materials: Based on hydration enhancement and phase evolution regulation. Constr. Build. Mater. 2024, 415, 134914.

[43] Wang R, Zhang Q, Li Y. Deterioration of concrete under the coupling effects of freeze–thaw cycles and other actions: A review. Constr. Build. Mater. 2022, 319, 126045.

[44] Kumaragamage, D.; Warren, C. J.; Spiers, C. J.; Soil Chemistry. Digging into Canadian Soils: An Introduction to Soil Science; Canadian Society of Soil Science, 2021.

[45] ong L, Ji J, Yang J, Qian X, Li X, Wang H, et al. Sludge-based ceramsite for environmental remediation and architecture ingredients. J. Clean. Prod. 2024, 448, 141556.

[46] Yao M, Wang Q, Ma B, Liu Y, Yu Q, Han Y. Effect of Freeze-Thaw Cycle on Shear Strength of Lime-Solidified Dispersion Soils. Civ. Eng. J. 2020, 6, 114-129.

[47] Huang M, Zhou M, Li Z, Ding X, Wen J, Jin C, Wang L, et al. How do drying-wetting cycles influence availability of heavy metals in sediment? A perspective from DOM molecular composition. Water Res. 2022, 220, 118671.

[48] He Y, Chen X, Peng Y, Luo ZB, Jiang SF, Jiang H. Investigation of the effects of biochar amendment on soil under freeze-thaw cycles and the underlying mechanism. Heliyon 2024, 10, e34907.

[49] Li Q, Wang Y, Li Y, Li L, Tang M, Hu W, et al. Speciation of heavy metals in soils and their immobilization at micro-scale interfaces among diverse soil components. Sci. Total Environ. 2022, 825, 153862.

[50] Wu L, Du W, Wang L, Cao Y, Lv J. Effects of freeze-thaw leaching on physicochemical properties and cadmium transformation in cadmium contaminated soil. Ecotoxicol. Environ. Saf. 2024, 284, 116935.

[51] Xie C, Cao M, Yin H, Guan J, Wang L. Effects of freeze-thaw damage on fracture properties and microstructure of hybrid fibers reinforced cementitious composites containing calcium carbonate whisker. Constr. Build. Mater. 2021, 300, 123872.

[52] Lv J, Zuo W, Tian C, Wang M, Liao Q, Lin Z. Freeze-accelerated reactions on environmental relevant processes. Cell Rep. Phys. Sci. 2023, 4, 101456.

[53] Zouaouid K, Gheriani R. Mineralogical Analysis of Sand Roses and Sand Dunes Samples from Two Regions of South Algeria. Silicon 2019, 11, 1537-1545.

[54] Shao S, Ma B, Chen Y, Zhang W, Wang C. Behavior and mechanism of fluoride removal from aqueous solutions by using synthesized CaSO₄·2H₂O nanorods. Chem. Eng. J. 2021, 426, 131364.

[55] Xiong H, Liu Y, Wang S, Zhu S. Schwertmannite and akaganeite for adsorption removals of Cr(VI) from aqueous solutions. Environ. Sci. Pollut. Res. 2023, 30, 62295-62311.

[56] Morebodi KB, Reddy L, Balakrishna A, Erasmus LJ, Swart HC, Masiteng PL. Investigation of photoluminescence properties and energy transfer in Sm³⁺ and Eu³⁺ co-doped Na₂Ca(SO₄)₂ nanophosphors prepared by combustion technique. Solid State Sci. 2022, 134, 107059.

[57] Lin S, Tian Y, Zhang W, Zhao T, Zhao M, Wang H. Enhanced photocatalytic activity over ZnO supported on calcium sulfate whisker derived from desulfurization gypsum. Korean J. Chem. Eng. 2022, 39, 3267-3276.

[58] Suzuki K, Katayama K, Sumii Y, Nakagita T, Suno R, Tsujimoto H, et al. Vibrational analysis of acetylcholine binding to the M(2) receptor. RSC Adv. 2021, 11, 12559-12567.

[59] Tuan Mohamood NFA, Abdul Halim AH, Zainuddin N. Carboxymethyl Cellulose Hydrogel from Biomass Waste of Oil Palm Empty Fruit Bunch Using Calcium Chloride as Crosslinking Agent. Polymers 2021, 13, 4056.

[60] Kathyola TA, Willneff EA, Willis CJ, Dowding PJ, Schroeder SL. Reactive CaCO₃ Formation from CO₂ and Methanolic Ca(OH)₂ Dispersions: Transient Methoxide Salts, Carbonate Esters and Sol-Gels. ACS Phys. Chem. Au 2024, 4, 555-567.

[61] Ma M, Xu X, Ha Z, Su Q, Lv C, Li J, et al. Deep insight on mechanism and contribution of arsenic removal and heavy metals remediation by mechanical activation phosphogypsum. Environ. Pollut. 2023, 336, 122258.

[62] Prabakaran K, Sufiyan KM, Kumar S, Jandas PJ, Manikandan VS, Thirumurugan A. Synthesis of zinc oxide and tin oxide (ZnO/SnO₂) nanocomposite for photoanode applications in dye sensitized solar cell. J. Mater. Sci. Mater. Electron. 2024, 35, 1993.

[63] Chen M, Hu H, Chen M, Wang C, Wang Q, Zeng C, et al. In-situ production of iron flocculation and reactive oxygen species by electrochemically decomposing siderite: An innovative Fe-EC route to remove trivalent arsenic. J. Hazard. Mater. 2023, 441, 129884.

[64] Tyszka R, Pietranik A, Potysz A, Kierczak J, Schulz B. Experimental simulations of Zn Pb slag weathering and its impact on the environment: Effects of acid rain, soil solution, and microbial activity. J. Geochem. Explor. 2021, 228, 106808.

[65] Wang X, Zhou Y, Feng F, Guo Y, Hao Z, Lu C, et al. Synthesis of high photoreactive flower-like ZnO nanoneedles assembly with exposed nonpolar {1010} facets oriented by carbon spheres. Appl. Surf. Sci. 2022, 598, 153799.

[66] La Porta FD, Nogueira AE, Gracia L, Pereira WS, Botelho G, Mulinari TA, et al. An experimental and theoretical investigation on the optical and photocatalytic properties of ZnS nanoparticles. J. Phys. Chem. Solids 2017, 103, 179-189.

[67] Badawy AA, Ghanem AF, Yassin MA, Youssef AM, Rehim MH. Utilization and characterization of cellulose nanocrystals decorated with silver and zinc oxide nanoparticles for removal of lead ion from wastewater. Environ. Nanotechnol. Monit. Manag. 2021, 16, 100501.

[68] Vu MH, Nguyen CC, Sakar M, Do TO. Ni supported CdIn₂S₄ spongy-like spheres: A noble metal free high-performance sunlight driven photocatalyst for hydrogen production. Phys. Chem. Chem. Phys. 2017, 19, 29429-29437.

[69] Zhang P, Liu Y, Tian B, Luo Y, Zhang J. Synthesis of core-shell structured CdS@CeO₂ and CdS@TiO₂ composites and comparison of their photocatalytic activities for the selective oxidation of benzyl alcohol to benzaldehyde. Catal. Today 2017, 281, 181-188.

[70] Shen J, Wang Q, Chen Y, Han Y, Zhang X, Liu Y. Evolution process of the microstructure of saline soil with different compaction degrees during freeze-thaw cycles. Eng. Geol. 2022, 304, 106699.