The zeolite modified by chitosan as an adsorbent for environmental applications

Abstract

Fly ash (FA) and zeolite Na-A obtained on it were modified by chitosan (CS) and investigated for heavy metal ions removal from aqueous solutions. FA-CS and Na-A-CS were characterized by the X-ray fluorescence method, X-ray diffraction, scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM/EDX), nitrogen adsorption/desorption measurements, Fourier transform infrared spectroscopy (FTIR) and atomic absorption spectroscopy (AAS) methods. Cation exchange capacity and pH zpc of used sorbents were also determined. The kinetic and sorption characteristics were made as regard Cu(II), Fe(III), Mn(II) and Zn(II) ions removal from one-and multi-ion solutions. It was found that the phase contact time (1-1440 min), pH (3-5), the amount of fly ash and zeolite (2.5-25 g/dm 3 ), the initial concentration of metal ions (20-240 mg/dm 3 ) and zeolite modification (glutaraldehyde and epichlorohydrin) affect the sorption process. The best adsorptions were obtained at 250 mg/L concentration, pH solution of about 5.0 and 120 min contact time for Cu(II), Fe(III), Mn(II) and Zn(II) ions. The results suggested that the sequence for sorption efficiency decreases in the order in the one-and multi-ion systems: Cu(II) > Fe(III) > Zn(II) > Mn(II).

Adsorption of Ni2+ and Cd2+ from Water by Calcium Alginate/Spent Coffee Grounds Composite Beads

“…q exp − q model 2 (7) where q exp is the experimental data, and q model is the value predicted by the model at the corresponding C e . To compare the applicability of isotherm equations and fitting it to the data, non-linear chi-square test χ 2 was calculated from Equation (8) [33]:…”

“…Waste minerals from construction work such as dolomite (cadmium sorption of 89.9 mg/g) are inexpensive adsorbents and they do not have any other practical application [6]. In the same way, synthetic mineral adsorbents made from waste material such as zeolite synthetized from fly ash product of power generation by coal (copper sorption of 4.99 mg/g) is another example of a raw material without additional applications [7]. Accessible clay minerals such as glauconite (cadmium sorption of 2.596 mg/g) have the advantage that are natural, locally available, commonly occurring materials and could be reused as a sustainable and environment-friendly building material [8].…”

Synthesis and Application of Ion‐Imprinted Nanoparticles in Electrochemical Sensors for Copper (II) Determination

“…[6] In order to enhance the sensitivity of the electrochemical determination of metal ions, several chemical modifications of electrode surfaces have been proposed in literature. The most used modifiers include bismuth [7,8] composites of carbon nanotubes, [9] carbon black, [10] chelating agents, [11] gold nanoparticles, [12,13] zeolite, [14] and graphene oxide. [15] On the other hand, nanomaterials based on the imprinting processes have been proposed in order to improve the selective determination of diverse analytes.…”

ADSORPTION OF M(II) (M = Mn, Cu, Zn) IN VARIOUS pH AND CONTACT TIME USING CHITOSAN-SILICA PREPARED BY SOL-GEL METHOD

“…Kyzas and Bikiaris summarised published studies (during 2012-2014) of modified chitosan for adsorption of dyes and metal ions including their adsorption capacity. 5 There are two main modifications of chitosan, namely by grafting (functional group insertion) or by cross-linking reaction (combining with the macromolecular unit), such as zeolite, [6][7] polyvinyl alcohol, 8 graphite oxide, 9 alumina, 10 3,4,5-trihydroxy benzoic acid, 11 trimethylamine sulphur trioxide, 12 silica, [13][14][15] cellulose acetate 16 etc. Many of these modifications resulting in adsorbent with better adsorption capacity and durability in extreme conditions.…”