Effects of pH and Anion Species on Cr(VI) Removal by Magnetite

Magnetite was prepared to remove poisonous hexavalent chromium [Cr(VI)] from aqueous solution. Batch experiments were conducted to measure the effects on removal of Cr(VI) of different parameters such as ionic strength, pH, and initial concentration. Results demonstrated that the removal of Cr(VI) on magnetite was decreased with the increase of pH in the range of 3.4-5.0, but independent of ionic strength. The removal percentage of Cr(VI) also decreased with the increase of Cr(VI) concentration in the range of 50-200 mg/L. At pH 3.5 and 5.0, the presence of SO42−retarded the removal of Cr(VI) via electrostatic interactions and/or competition for surfaces sites on magnetite. The pH of the medium and presence of anion species were critical factors in the removal of Cr(VI) from aqueous solution.

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Adsorption of Cu(II) on maghnite from aqueous solution: Effects of pH, initial concentration, interaction time and temperature

Natural Science ◽

10.4236/ns.2012.411114 ◽

2012 ◽

Vol 04 (11) ◽

pp. 856-868 ◽

Cited By ~ 4

Author(s):

Mohamed Amine Zenasni ◽

Said Benfarhi ◽

André Merlin ◽

Stéphane Molina ◽

Béatrice George ◽

...

Keyword(s):

Aqueous Solution ◽

Interaction Time ◽

Initial Concentration ◽

Effects Of Ph

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Dyes Adsorption onto Fe 3 O 4 ‐Bis(trimethoxysilylpropyl)amine Composite Particles: Effects of pH and Ionic Strength on Electrostatic Interactions

ChemistrySelect ◽

10.1002/slct.201803241 ◽

2019 ◽

Vol 4 (2) ◽

pp. 617-622 ◽

Cited By ~ 5

Author(s):

Yaoqiang Hu ◽

Kexin Li ◽

Yuting Li ◽

Haining Liu ◽

Min Guo ◽

...

Keyword(s):

Ionic Strength ◽

Electrostatic Interactions ◽

Composite Particles ◽

Effects Of Ph ◽

Dyes Adsorption

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Enhancement of decomposition of 2-chlorophenol with ultrasound/H2O2 process

Water Science & Technology ◽

10.2166/wst.1996.0173 ◽

1996 ◽

Vol 34 (9) ◽

pp. 41-48 ◽

Cited By ~ 17

Author(s):

Jih-Gaw Lin ◽

Cheng-Nan Chang ◽

Jer-Ren Wu ◽

Ying-Shih Ma

Keyword(s):

Ionic Strength ◽

Reaction Rate ◽

Order Reaction ◽

Pseudo First Order Reaction ◽

Initial Concentration ◽

First Order ◽

Toc Removal ◽

Cp Decomposition ◽

Effects Of Ph ◽

Pseudo First Order

We investigated the effects of pH, ionic strength, catalyst, and initial concentration on both decomposition of 2-chlorophenol (2-cp) and removal of total organic carbon (TOC) in aqueous solution with ultrasonic amplitude 120 μm and H2O2 (200 mg/l). When the initial concentrations of 2-cp was 100 mg/l and the pH was controlled at 3, the rate of 2-cp decomposition was enhanced up to 6.6-fold and TOC removal up to 9.8-fold over pH controlled at 11. At pH 3, the efficiency of decomposition of 2-cp was 99% but the removal of TOC was only 63%; a similar situation applied at pH 7 and 11. Hence intermediate compounds were produced and 2-cp was not completely mineralized. When the concentration of ionic strength was increased from 0.001 to 0.1 M, the rate of 2-cp decomposition was enhanced only 0.3-fold, whereas the TOC removal was not enhanced. In comparison of the effects of pH and ionic strength, pH had greater influence on both 2-cp decomposition and TOC removal than ionic strength. The effect of a catalyst (FeSO4) on decomposition of 2-cp was insignificant comparing with direct addition of H2O2. The reaction rate at a smaller initial concentration of 2-cp (10 mg/l) was more rapid than at a greater one (100 mg/l). The rate of 2-cp decomposition and TOC removal appeared to follow pseudo-first-order reaction kinetics.

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Sorption of Cr(VI) onto natural iron and aluminum (oxy)hydroxides: Effects of pH, ionic strength and initial concentration

Journal of Hazardous Materials ◽

10.1016/j.jhazmat.2009.09.096 ◽

2010 ◽

Vol 174 (1-3) ◽

pp. 616-622 ◽

Cited By ~ 138

Author(s):

Omar Ajouyed ◽

Charlotte Hurel ◽

Mohammed Ammari ◽

Laïla Ben Allal ◽

Nicolas Marmier

Keyword(s):

Ionic Strength ◽

Initial Concentration ◽

Natural Iron ◽

Effects Of Ph

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Study of Distribution Coefficient of 90Sr on Citumbuk Bentonite and Sukaramai Kaolinite

EKSPLORIUM ◽

10.17146/eksplorium.2017.38.1.3056 ◽

2017 ◽

Vol 38 (1) ◽

pp. 1

Author(s):

Budi Setiawan ◽

Heni Suseno

Keyword(s):

Ionic Strength ◽

Distribution Coefficient ◽

The Other ◽

Batch Experiments ◽

Initial Concentration ◽

Kd Values

ABSTRACTThe study of distribution coefficient of strontium on bentonite and kaolinite samples, collected from Citumbuk, Bogor and Sukaramai, Padang, has been investigated under batch experiments. The sorption ratio was determined as a function of time, ionic strength and Sr concentration in the solution. The strontium wasextensively absorbed in the samples, with Kd values of 13,700 and 1,600 mL/g for bentonite and kaolinite samples respectively. The other results showed that ionic strength of the solution and initial concentration of Sr have given an effect to 90Sr sorption onto samples. ABSTRAKStudi tentang koefisien distribusi dari stronsium pada sampel bentonit dan kaolin yang diambil dari lokasi Citumbuk, Bogor dan Sukaramai, Padang, telah diteliti secara catu. Rasio penyerapan ditentukan sebagai fungsi waktu, kekuatan ionic dan konsentrasi Sr di larutan. Stronsium telah terserap dengan baik pada sampel, dengan nilai Kd adalah 13.700 dan 1.600 mL/g masing-masing untuk sampel bentonite dan kaolin. Hasil lainnya menunjukkan bahwa kekuatan ionik dan konsentrasi awal Sr di larutan telah memberikan pengaruh pada penyerapan 90Sr ke dalam sampel.

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Reduction and Biosorption of Cr from Aqueous Solution Using Banana Skin

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.518-523.2708 ◽

2012 ◽

Vol 518-523 ◽

pp. 2708-2711 ◽

Cited By ~ 1

Author(s):

Ming Zhou ◽

Hang Xu ◽

Shu Fa Zhu ◽

Ya Na Liu

Keyword(s):

Aqueous Solution ◽

Aqueous Solutions ◽

Contact Time ◽

Low Cost ◽

Experimental Results ◽

Initial Concentration ◽

Effects Of Ph

The possible use of biowaste-banana skin as an alternative, low-cost biosorbent and reductant for removal of Cr from aqueous solutions was investigated. Effects of pH, contact time, Cr(VI) initial concentration and temperature on the reduction and biosorption of Cr by banana skin were studied. Experimental results showed that 1 g of dried banana skin could reduce about 230 mg of Cr(VI) to Cr(III), at the condition of 30°C, pH 2 and 300 rpm. The maximum Qeq of Cr(III) by banana skin was 6.3mg g-1 at the Cr(VI) initial concentration of 200mg L-1, 30°C , pH 2 and 300 rpm.

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