Adsorption of methylene blue dye from aqueous solutions onto walnut shells powder: Equilibrium and kinetic studies

Han

Journal of Food Science

et al. 2020

In this study, triethylene tetramine-modified water-insoluble corn flour caged in magnetic chitosan resin (TETA-WICF/MCR) was firstly prepared, which indicates novel aspects for immobilization and chemically modification of mycotoxin adsorbents. The TETA-WICF/MCR was characterized using zoom stereo microscope, scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, X-ray diffractometer (XRD), and magnetic separation performance analysis. Experimental results confirmed successful layer by layer modification of chitosan, biosorbent water-insoluble corn flour (WICF), TETA onto the surface of magnetic beads. The mean diameter of the TETA-WICF/MCR was 2.63 mm with good magnetic-responsive ability. Subsequently, the adsorption performance of the TETA-WICF/MCR obtained toward patulin was assessed in batch adsorption system and the results demonstrated that the adsorption process was strongly depended on adsorbent dosage, contact time, temperature, and initial patulin concentration. The results of SEM images and FTIR analysis showed obvious changes in the porous structure of TETA-WICF/MCR after adsorbing patulin, and -NH 2 and -OH groups were predominantly involved in the adsorption of patulin. Furthermore, the adsorption kinetics followed the mechanism of pseudo-second-order model, and equilibrium data were well fitted in the Freundlich isotherm model. It was also found that the TETA-WICF/MCR had good reusability without any adverse changes in apple juice.

Section: Methodsmentioning

confidence: 99%

Synthesis of triethylene tetramine–modified water‐insoluble corn flour caged in magnetic chitosan resin and its adsorption application for removal of patulin from apple juice

Han

Journal of Food Science

et al. 2020

“…The surface morphology adsorbents were studied by scanning electron microscopy (SEM) analysis 'Tescan Vega 3'. Determination of point zero charge (pH PZC ) was performed according to the method described by Miyah et al [11]. In brief, solutions of 0.01 M NaCl (50 ml) were adjusted to pH range of 2-12 by adding drops of 0.1 M HCl or 0.1 M NaOH.…”

Section: Characterization Of Samplesmentioning

confidence: 99%

Zn-Al layered double hydroxide: synthesis, characterization and application for orthophosphates ions adsorption in aqueous medium

Rouahna

Ouakouak

Srasra

2020

Mater. Res. Express

This paper aims at studying the preparation of Zn-Al-LDH anionic clay and its adsorption proprieties in removing orthophosphate ions from aqueous medium. The LDH phase was synthesized by coprecipitation method and then calcined at 500°C. Structural and textural properties of the prepared LDHs were determined by using x-ray diffraction, FTIR, BET, SEM and pH PZC analysis. Batch adsorption experiments were carried out under different parameters such as stirring time, pH and initial orthophosphate concentration. Results show that the prepared LDHs are efficient in removing orthophosphate and the maximum uptake was observed after 2 h. Experimental kinetic data are well described by the pseudo-second order model. It was also found that the adsorption process is significantly affected by the pH value. The sorption mechanisms include ion exchange, reconstitution of LDH phase and/or electrostatic attraction. Also, the isotherm study reveals that the Freundlich equation best fit the equilibrium data.

“…Among the different processes for purifying effluents loaded with heavy metals, adsorption, which involves fixing the pollutant load at the interface through physical or chemical bonds, offers better performance and fewer problems compared with other advanced processes [17,18]. Adsorption also offers an economical solution by developing sorbents with a much lower cost [18][19][20][21][22].…”

Section: Introductionmentioning

confidence: 99%

Continuous Adsorption Modeling and Fixed Bed Column Studies: Adsorption of Tannery Wastewater Pollutants Using Beach Sand

Mouhri

Merzouki²,

Belhassan³

et al. 2020

Journal of Chemistry

Self Cite

is study deals with the removal of residual pollutants from tanning wastewater by continuous adsorption mechanism, using local sand as a low-cost adsorbent. e possibility of pretreating a complex tannery effluent heavily loaded with a natural material such as sand is significant. e characterization of the adsorbent before and after continuous adsorption was performed by X-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy. Column studies were also carried out to evaluate the performance of the adsorbent and the efficiency of column adsorption. e adsorption kinetic rate seems to be strongly influenced by certain parameters such as the particle size of the material used, the withdrawal rate of the influent and the height of the adsorbent bed, and optimized parameters were found to be 63 μm, 15 ml·min − 1 , and 7 cm, respectively, and the color removal has achieved maximum values which vary between 95 and 100%. e results suggest that sand can be used as an economical adsorbent for the removal of color from the wastewater of the tanning industries.