Polyethyleneimine-grafted polysilsesquioxane hollow spheres for the highly efficient removal of anionic dyes and selective adsorption of Cr(VI)

Yan, Yong‐Zhu; Nagappan, Saravanan; Yoo, Jongman; Nechikkattu, Riyasudheen; Ha, Chang‐Sik

doi:10.1016/j.jece.2020.104814

Cited by 25 publications

(7 citation statements)

References 67 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The Freundlich isotherm explains the multilayer adsorption and heterogeneous adsorbent systems. The nonlinear Langmuir model Equations (2) and (3), and the Freundlich model Equation (4), are expressed as follows [ 26 , 32 ]:

where q e (mg/g) and q m (mg/g) are the amount of Cr(VI) adsorbed on SBA-15-NH 2 and CB18crown6/SBA-15 at the equilibrium and the maximum adsorption capacity, respectively, Ce (mg/L) is the equilibrium concentration of Cr(VI), K (L/mg) is the Langmuir constant, K f represents the Freundlich constant—which is an indicator of adsorption capacity—and 1/n is the adsorption strength of the system.…”

Section: Resultsmentioning

confidence: 99%

“…The adsorbed amount, q e (mg/g), was estimated using the following equation:

where C 0 (mg/L) is the initial concentration of a metal ion adsorbate, C e (mg/L) is the equilibrium concentration of the metal ion adsorbate, V (mL) is the volume of the solution, and m (mg) is the mass of the adsorbent [ 26 ].…”

Section: Methodsmentioning

confidence: 99%

“…The Freundlich isotherm explains the multilayer adsorption and heterogeneous adsorbent systems. The nonlinear Langmuir model Equations ( 2) and ( 3), and the Freundlich model Equation ( 4), are expressed as follows [26,32]:…”

Section: Adsorption Performance and Selective Adsorptionmentioning

confidence: 99%

See 2 more Smart Citations

Crown-Ether-Modified SBA-15 for the Adsorption of Cr(VI) and Zn(II) from Water

Yoo¹,

Yan²,

Ha³

2021

Materials

Self Cite

View full text Add to dashboard Cite

Recently, the release of some metal ions to the environment has been observed to cause serious damages to human health and the environment. Herein, a chromium(VI)- and zinc(II)-selective adsorbent (CB18crown6/SBA-15) was successfully fabricated through the covalent attachment of 4′-carboxybenzo-18-crown-6 (CB18crown6) as a ligand on mesoporous silica support (SBA-15). The CB18crown6/SBA-15 adsorbent was characterized by Fourier-transform infrared (FTIR) spectrometry, X-ray diffraction (XRD), N2 adsorption–desorption, thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). To evaluate its ability to selectively capture Cr(VI) and Zn(II), adsorption experiments were conducted. The influences of pH, initial concentration of metal ions, and coexisting metal ions on the adsorption process were examined. The CB18crown6/SBA-15 selectively adsorbed Cr(VI) at pH 2 and Zn(II) at pH 5, respectively, from the mixed aqueous solutions of chromium, zinc, lithium, cadmium, cobalt, strontium, and cesium ions. The data for the adsorption of Cr(VI) onto the CB18crown6/SBA-15 were well explained by the Langmuir adsorption isotherm. In addition, the recycling and reuse of CB18crown6/SBA-15 was successfully achieved, and 71 and 76% reuse efficiency of Cr(VI) and Zn(II), respectively, was obtained after five cycles. This study suggests that the use of the CB18crown6/SBA-15 can be a feasible approach for the selective remediation of Cr(VI) and Zn(II) contamination.

show abstract

Section: Resultsmentioning

confidence: 99%

“…The adsorbed amount, q e (mg/g), was estimated using the following equation:

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

Crown-Ether-Modified SBA-15 for the Adsorption of Cr(VI) and Zn(II) from Water

Yoo¹,

Yan²,

Ha³

2021

Materials

Self Cite

View full text Add to dashboard Cite

show abstract

“…The adsorption capacities of Congo red (CR) and hexavalent chromium Cr(VI) on H-PVTMS-PEI-2 were 922.4 and 391.1 mg g −1 , respectively. 24 Other studies have also found that PEI shows excellent Cr(VI) adsorption and reduces highly toxic Cr(VI) to innoxious Cr(III) because the amino groups (electron donors) can provide electrons. 30 To fully exploit the excellent adsorption performance of PEI, its introduction into other materials with large specic surface areas is a practical approach.…”

Section: Introductionmentioning

confidence: 98%

“…Polyethylenimine (PEI) with good reactivity and chelating ability has been reported to be a potential candidate in the wastewater treatment eld owing to the existence of primary and secondary amine groups. 24,25 In an acidic environment, the protonation of amino groups conduces to form electrostatic interactions with anionic metal complex and anionic dyes. 26 However, single PEI as an adsorbent is still difficult to separate and regenerate from adsorption solution.…”

Section: Introductionmentioning

confidence: 99%