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Treatment of wastewaters containing acid, reactive and direct dyes using aminosilane functionalized silica

100%

Wawrzkiewicz M., Hubicki Z., Nowacka M., Klapiszewski Ł.

Open Chemistry

2015

vol. 13

issue 1

Aminosilane modified silica was prepared and investigated for the adsorption of textile dyes such as C.I. Acid Orange 7 (AO7), C.I. Reactive Black 5 (RB5) and C.I. Direct Blue 71 (DB71) from aqueous media and wastewaters. The values of the sorption capacities obtained from the Langmuir isotherm model were: 5.3 mg g-1, 58.7 mg g-1 and 72.2 mg g-1 for AO7, DB71 and RB5, respectively. The affinity series of the dyes for the modified silica can be presented as follows: C.I. Reactive Black 5 > C.I. Direct Blue 71> C.I. Acid Orange 7. The influence of anionic surfactant (SDS) and sodium chloride on dye sorption was investigated in a system containing 100 mg L-1 dye and 0.1-1 g L-1 SDS or 1-25 g L-1 NaCl. The sorption capacities decrease with increasing concentration of SDS in the solution. Retention of AO7 and RB5 was reduced in the presence of NaCl. A satisfactory agreement of the experimental data with the pseudo second-order kinetic model was found. Effectiveness of the aminosilane modified silica in raw textile wastewater purification was confirmed.

Nano sized carbonized waste biomass for heavy metal ion remediation

100%

Mahajan G., Sud D.

Polish Journal of Chemical Technology

2014

vol. 16

issue 4

6-13

Utilization of agricultural waste material with approach to enhance the heavy metal remediation properties by carbonizing the biomass at nano size particles has been explored in present investigation from aqueous solutions. In this study the lignocellulosic, nitrogenous agricultural waste biomass Delbergia sissoo pods (DSP) has been tried for sequestering of Cd (II), Pb (II) and Ni (II) metal ions from aqueous solutions. Batch experiments were performed for removal of targeted metal ions keeping in consideration the preliminary affecting parameters such as effect of adsorption dose, pH, initial metal ion concentration, stirring speed and contact time. The sorption studies were analyzed by using, Freundlic isotherm and Langmuir isotherm models. The kinetics of the process was evaluated by pseudo pseudo-first order and pseudo second order kinetic models. Studies reveal that the equilibrium was achieved with in 30 min of the contact time at optimized parameters. Analytical studies of biosorbent were done by means of FT-IR, SEM and XRD. Desorption experiments were carried out using HCl solution with a view to regenerate the spent adsorbent and to recover the adsorbed metal ions.

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1 Open Chemistry

1 Polish Journal of Chemical Technology

1 2015

1 2014

1 Hubicki Z.

1 Klapiszewski Ł.

1 Mahajan G.

1 Nowacka M.

1 Sud D.

1 Wawrzkiewicz M.

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Treatment of wastewaters containing acid, reactive and direct dyes using aminosilane functionalized silica

Nano sized carbonized waste biomass for heavy metal ion remediation