Effect of Mn substitution on the oxidation/adsorption abilities of iron(III) oxyhydroxides

Cho, Dong-Wan; Chon, Chul-Min; Yang, Hyuncheol; Tsang, Yiu Fai; Song, Hocheol

doi:10.1007/s10098-018-1528-0

Cited by 7 publications

(2 citation statements)

References 32 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In this last case, the kinetic model showed constants of k 2 = 0.1866 (g mg −1 min −1 ) and q e = 0.425 (mg g −1 ). On the other hand, smaller k 2 values, below 0.01 mg g −1 min −1 , were shown by Yang et al [40] in the adsorption of As(III) by ZnO microtubes; and also in adsorption experiments at similar initial concentrations of Mn@FeO x composites [41]. It is worth noting that for all of these cases, the results of this study with CTO showed higher qe even at pH 7.…”

Section: Resultscontrasting

confidence: 46%

As(III) Removal from Aqueous Solution by Calcium Titanate Nanoparticles Prepared by the Sol Gel Method

et al. 2019

View full text Add to dashboard Cite

Arsenic (As) contamination of water is a serious problem in developing countries. In water streams, arsenic can be as As(V) and As(III), the latter being the most toxic species. In this work, an innovative adsorbent based on CaTiO3 nanoparticles (CTO) was prepared by the sol-gel technique for the removal of As(III) from aqueous solution. X-ray diffraction of the CTO nanoparticles powders confirmed the CTO phase. Transmission electron microscopy observations indicated an average particle size of 27 nm, while energy dispersive X-ray spectroscopy analysis showed the presence of Ca, Ti, and O in the expected stoichiometric amounts. The surface specific area measured by Brunauer, Emmett, and Teller (BET) isotherm was 43.9 m2/g, whereas the isoelectric point determined by Zeta Potential measurements was at pH 3.5. Batch adsorption experiments were used to study the effect of pH on the equilibrium adsorption of As(III), using an arsenite solution with 15 mg/L as initial concentration. The highest removal was achieved at pH 3, reaching an efficiency of up to 73%, determined by X-ray fluorescence from the residual As(III) in the solution. Time dependent adsorption experiments at different pHs exhibited a pseudo-second order kinetics with an equilibrium adsorption capacity of 11.12 mg/g at pH 3. Moreover, CTO nanoparticles were regenerated and evaluated for four cycles, decreasing their arsenic removal efficiency by 10% without affecting their chemical structure. X-ray photoelectron spectroscopy analysis of the CTO surface after removal experiments, showed that arsenic was present as As(III) and partially oxidized to As(V).

show abstract

Section: Resultscontrasting

confidence: 46%

As(III) Removal from Aqueous Solution by Calcium Titanate Nanoparticles Prepared by the Sol Gel Method

et al. 2019

View full text Add to dashboard Cite

show abstract

“…Although arsenite is more toxic and prevalent in groundwater, it has less affinity towards adsorbent surface due to its non-ionic nature, whereas arsenate exists as ionic species in the pH range of 4-10 which makes it easily removable. In general, for arsenite removal, pre-oxidation is involved which converts arsenite into arsenate, then it gets removed from the aqueous solution (Cho et al, 2018). Therefore, for the present study, only arsenate removal has been considered.…”

Section: Introductionmentioning

confidence: 99%

Use of adsorption-influencing parameters for designing the batch adsorber and neural network–based prediction modelling for the aqueous arsenate removal using combustion synthesised nano-alumina

Prabhakar

Samadder

2020

Environ Sci Pollut Res

View full text Add to dashboard Cite

Removal of arsenic from water is of utmost priorities on a global scenario due to its ill effects. Therefore, in the present study, aluminium oxide nano-particles (nano-alumina) were synthesised via solution combustion method, which is self-propagating and eco-friendly in nature. Synthesised nano-alumina was further employed for arsenate removal from water. Usually, pre-oxidation of arsenite is performed for better removal of arsenic in its pentavalent form. Thus, arsenate removal as a function of influencing parameters such as initial concentration, dose, pH, temperature, and competing anions was the prime objective of the present study. The speciation analysis showed that H 2 AsO4and HAsO 4 2− were co-existing anions between pH 6 and 8, as a result of which higher removal was observed. Freundlich isotherm model was well suited for data on adsorption. At optimal temperature of 298 K, maximum monolayer adsorption capacity was found as 1401.90 μg/g. The kinetic data showed film diffusion step was the controlling mechanism. In addition, competing anions like nitrate, bicarbonate, and chloride had no major effect on arsenate removal efficiency, while phosphate and sulphate significantly reduced the removal efficiency. The negative values of thermodynamic parameters ΔH°(− 23.15 kJ/mol) established the exothermic nature of adsorption, whereas the negative values of ΔG°(

show abstract

Bulk and surface theoretical investigation of Nb-doped δ-FeOOH as a promising bifunctional catalyst

et al. 2021

View full text Add to dashboard Cite

Effect of Mn substitution on the oxidation/adsorption abilities of iron(III) oxyhydroxides

Cited by 7 publications

References 32 publications

As(III) Removal from Aqueous Solution by Calcium Titanate Nanoparticles Prepared by the Sol Gel Method

As(III) Removal from Aqueous Solution by Calcium Titanate Nanoparticles Prepared by the Sol Gel Method

Use of adsorption-influencing parameters for designing the batch adsorber and neural network–based prediction modelling for the aqueous arsenate removal using combustion synthesised nano-alumina

Bulk and surface theoretical investigation of Nb-doped δ-FeOOH as a promising bifunctional catalyst

Contact Info

Product

Resources

About