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Huang Y, Tang Y, Liang Y, Xie Z, Wu J, Huang J, Wei S, Nie S, Jiang T. Transport and retention of n-hexadecane in cadmium-/naphthalene-contaminated calcareous soil sampled in a karst area. ENVIRONMENTAL GEOCHEMISTRY AND HEALTH 2023; 45:8881-8895. [PMID: 37358714 DOI: 10.1007/s10653-023-01664-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2022] [Accepted: 06/13/2023] [Indexed: 06/27/2023]
Abstract
Studying the transport of petroleum hydrocarbons in cadmium-/naphthalene-contaminated calcareous soils is crucial to comprehensive assessment of environmental risks and developing appropriate strategies to remediate petroleum hydrocarbons pollution in karst areas. In this study, n-hexadecane was selected as a model petroleum hydrocarbon. Batch experiments were conducted to explore the adsorption behavior of n-hexadecane on cadmium-/naphthalene-contaminated calcareous soils at various pH, and column experiments were performed to investigate the transport and retention of n-hexadecane under various flow velocity. The results showed that Freundlich model better described the adsorption behavior of n-hexadecane in all cases (R2 > 0.9). Under the condition of pH = 5, it was advantageous for soil samples to adsorb more n-hexadecane, and the maximum adsorption content followed the order of: cadmium/naphthalene-contaminated > uncontaminated soils. The transport of n-hexadecane in cadmium/naphthalene-contaminated soils at various flow velocity was well described by two kinetic sites model of Hydrus-1D with R2 > 0.9. Due to the increased electrostatic repulsion between n-hexadecane and soil particles, n-hexadecane was more easily able to breakthrough cadmium/naphthalene-contaminated soils. Compared to low flow velocity (1 mL/min), a higher concentration of n-hexadecane was determined at high flow velocity, with 67, 63, and 45% n-hexadecane in effluent from cadmium-contaminated soils, naphthalene-contaminated soils, and uncontaminated soils, respectively. These findings have important implications for the government of groundwater in calcareous soils from karst areas.
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Affiliation(s)
- Yiting Huang
- School of Civil Engineering and Architecture, Guangxi University, Nanning, 530004, China
| | - Yankui Tang
- School of Resources, Environment and Materials, Guangxi University, Nanning, 530004, China.
| | - Yi Liang
- School of Resources, Environment and Materials, Guangxi University, Nanning, 530004, China
| | - Zhenze Xie
- School of Resources, Environment and Materials, Guangxi University, Nanning, 530004, China
| | - Jipeng Wu
- School of Resources, Environment and Materials, Guangxi University, Nanning, 530004, China
| | - Jiajie Huang
- School of Resources, Environment and Materials, Guangxi University, Nanning, 530004, China
| | - Shanxiong Wei
- School of Resources, Environment and Materials, Guangxi University, Nanning, 530004, China
| | - Shaojiang Nie
- School of Resources, Environment and Materials, Guangxi University, Nanning, 530004, China
| | - Tao Jiang
- School of Resources, Environment and Materials, Guangxi University, Nanning, 530004, China
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Single and Binary Adsorption Systems of Rhodamine B and Methylene Blue onto Alkali-Activated Vietnamese Diatomite. ADSORPT SCI TECHNOL 2021. [DOI: 10.1155/2021/1014354] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Diatomite was slightly modified with a sodium hydroxide solution. The resulting material was characterized by using energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and nitrogen adsorption-desorption isotherms. The so-treated diatomite has a high specific surface area (77.8 m2/g) and a high concentration of isolated silanol groups on the surface, and therefore, its adsorption capacity increases drastically in both the single and binary adsorption systems for rhodamine B and methylene blue. The binary system is more effective than the single system, with methylene blue being adsorbed more than rhodamine B. The adsorption process is spontaneous and fits well with the Langmuir isothermal model, and it depends on pH significantly.
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