Simultaneous removal of Cd(II) and ionic dyes from aqueous solution using magnetic graphene oxide nanocomposite as an adsorbent

Nistor

et al. 2018

Journal of Chemistry

This work develops a methodology for selective removal of industrial dyes from wastewaters using adsorption technology based on magnetic adsorbents. The magnetic nanoparticles embedded within a matrix of activated carbon were tested as adsorbents for removal of industrial dyes from aqueous solutions. The effects of four independent variables, solution pH, initial concentration of pollutant, adsorbent dose, contact time, and their interactions on the adsorption capacity of the nanocomposite were investigated in order to optimize the process. The removal efficiency of pollutants depends on solution pH and increases with increasing the carbon content, with initial concentration of the pollutants, the temperature, and the dose of magnetite/carbon nanocomposites. Pseudo-second-order kinetic model was fitted to the kinetic data, and adsorption isotherm analysis and thermodynamics were used to elucidate the adsorption mechanism. The maximum adsorption capacities were 223.82 mg g −1 for Nylosan Blue, 114.68 mg g −1for Chromazurol S, and 286.91 mg g −1 for Basic Red 2. The regeneration and reuse of the sorbent were evaluated in seven adsorption/desorption cycles. The optimum conditions obtained for individual adsorption were selected as starting conditions for simultaneous adsorption of dyes. In binary systems, in normal conditions, selectivity decreases in the order: Red Basic 2 > Nylosan Blue > Chromazurol S.

Section: Adsorption Isothermssupporting

confidence: 79%

Removal of Colored Organic Pollutants from Wastewaters by Magnetite/Carbon Nanocomposites: Single and Binary Systems

Nistor

et al. 2018

Journal of Chemistry

Current Opinion in Colloid & Interface Science

“…However, for application realization, efficient recovery post-sorption is required. Covalently binding GO to magnetic nanoparticles has been attempted but requires high energy, complex and multistep synthetic procedures and effects adsorption capacity of the sheets [60,61]. Tabor et al used magnetic surfactants (DTAF) to bind to the GO (at pH 5.5 to ensure GO had a negative charge) [62].…”

Section: Adsorption On Inorganic Surfacesmentioning

confidence: 99%

Magnetic surfactants

Brown

Hatton

Eastoe

2015

General rightsThis document is made available in accordance with publisher policies. Please cite only the published version using the reference above. Full terms of use are available: http://www.bristol.ac.uk/pure/about/ebr-terms The use of these magneto-surfactants as novel molecular magnets is also investigated as well as looking forward to potential applications. Graphical AbstractHighlights  Introduce the 3 existing classes of magnetic surfactants; ionic, coordinating, covalently bound  Consider a potential 4 th class of magnetic surfactant  Describe how these surfactants function as molecular magnets  Report potential applications ranging biochemistry to water treatment  Discuss the origins of magnetism in dilute aqueous solutions

“…... (8) ...(9) The values of q m and K L are calculated from the slope and the intercept of the straight line plot of C e /q e versus C e , respectively (Fig. 4(a)).…”

Section: Adsorption Isothermmentioning

confidence: 99%

Adsorptive Removal of Manganese (II) from Aqueous Solution using Graphene Oxide: A Kinetics and Thermodynamics Study

Suddai¹,

Nuengmatcha²,

Chanthai³

2017

Orient. J. Chem

An excess amount of manganese is known to affect neurological toxicity. This study focused on adsorptive removal of Mn(II) using graphene oxide, which was carried out under optimum conditions after varying some experimental effects including pH, an incubation time and an initial concentration. It was demonstrated that Mn(II) adsorption follows both Langmuir and Freundlich isotherms. The maximum adsorption capacity for Mn(II) removal from an aqueous solution was 41.67 mg/g at pH 5 and their adsorption state was completed within 30 min. The adsorption kinetics was in accordance with pseudo second-order kinetic model. In thermodynamics diversion, changes in free energy, enthalpy and entropy were also studied. Overall, the adsorption process was exothermic and spontaneous in nature.