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Your search keyword '"Xue, Hongqin"' showing total 2 results
Start Over Author "Xue, Hongqin" Topic activated carbon
2 results on '"Xue, Hongqin"'

1. Adsorption of Nickel(II) with Composite Filter Material Made of Coal Fly Ash

Author

Xue Hongqin, Zheng Wang, Lin Shaohua, and Zhaoqian Jing

Subjects
inorganic chemicals, Arrhenius equation, Materials science, Aqueous solution, chemistry.chemical_element, Langmuir adsorption model, Mineralogy, Nickel, symbols.namesake, Adsorption, chemistry, Chemical engineering, Fly ash, medicine, symbols, Carbon, Activated carbon, medicine.drug
Abstract

The regular methods for nickel removal such as activated carbon adsorption are always complicated in process and expensive in construction and maintenance. In this research coal fly ash, usually taken as industrial waste, was synthesized into particle filter material, and then the latter was used as absorbent for nickel removal from aqueous water. The physical and chemical properties of this material were studied by scanning electron microscope (SEM) and energy dispersive X-ray spectrometry (EDS). Results indicated that this material had high porosity and large surface area. The main elements of this material were oxygen, silicon, carbon, aluminum, iron, calcium and magnesium. In the batch experiments for the application of this filter material in nickel removal, the effects of contact time, pH and temperature were studied. The batch experiments showed an equilibrium time of 90 min was required for effective adsorption of nickel. Removal ratio of nickel increased greatly at pH 5.5-6.5. More than 90% of nickel was removed with solution pH above 6.5. Adsorption rate constant (k) increased as temperature (T) rose. The equation describing the relation of k and T complied to Arrhenius equation, which indicated the adsorption of nickel on this filter material had some characteristics of chemical reaction. The adsorption isotherm of nickel accorded with Langmuir model.

Published
2009

2. Assessment of activated carbon as a sorbent amendment for immobilizing perfluoroalkyl acids for surface sediment remediation.

Author

Yu, Liang, Hua, Zulin, Liu, Xiaodong, and Xue, Hongqin

Subjects
*ACTIVATED carbon, *FLUOROALKYL compounds, *SEDIMENTS, *CONDITIONED response, *WATER levels, *DISSOLVED organic matter, *IONIC strength
Abstract

[Display omitted] • Shorter-chain PFAAs show pH- and ionic strength-dependent sorption on AC. • DOM competes with longer-chain PFAAs but increases shorter-chain one sorption. • AC displays long-term and superior performance in immobilizing sediment PFAAs. • AC significantly reduced 45.5%–99.2% PFAA release under various disturbances. • After intense disturbance stopped, water PFAAs fell to initial levels or lower. The detection of elevated levels of perfluoroalkyl acids (PFAAs) in sediments has become a significant concern, urgently requiring management and remediation efforts. In this study, we investigated the effectiveness of industrially cost-effective activated carbon (AC) in remediating PFAA-contaminated sediments at different disturbance intensities and explored the sorption capacity of AC under broad environmentally relevant conditions and in response to environmental variations. AC exhibited high sorption effectiveness for PFAAs (excluding perfluorobutanoic acid < 40 %) across different pH, ionic strengths (IS), and dissolved organic matter (DOM). However, the increase in pH or reduction in IS might reactivate partially immobilized PFAAs. DOM outcompeted longer-chain PFAAs for sorption sites, resulting in their reactivation on AC, while it showed a stronger sorption than a competitive effect on shorter-chain PFAAs. The 192-day remediation experiment showed that AC significantly deactivated mobile PFAAs and decreased PFAA release by 45.5 %–99.2 % and 61.0 %–98.8 % under weak and intense disturbances, respectively, when compared with untreated sediment. Although intense disturbance led to an increase in PFAA release, the PFAA levels in the water column of the AC group after intense disturbance were comparable or even lower than those before intense disturbance, primarily owing to the secondary sorption of suspended AC. These findings are crucial for the appropriate and safe use of AC for PFAA sequestration, the management of PFAA-contaminated sediments, and the development of effective sediment remediation strategies. [ABSTRACT FROM AUTHOR]

Published
2024
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