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

Abstract

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.

Synthesis and characterization of two-dimensional (2D) nanosheet zinc aluminum layered double hydroxide (Zn/Al LDH) via an alkali-free route

“…The higher the molar ratio used can attribute to an increase in the values of lattice parameter (a and c). Therefore, the crystal size was small as the higher molar ratio was used in the synthesis of Zn/Al LDH [11]. To support this finding, the samples' morphology was observed by characterizing them with SEM as showing in Figure 2.…”

Synthesis of BiFeO3/ZnMgAl-LDH nanocomposite for instantaneous decolorization of methylene blue by ultrasonic induced adsorption system: characterization and equilibrium studies

“…Moreover, the adsorption band at 732-532 cm −1 is associated with M-OH vibration. Bands at 432-558 cm −1 can be related to M-O and M-O-M stretching vibrations [50,51]. The broad band of BFO located at 3000-3500 cm −1 is attributed to stretching O-H, but at 1650 cm −1 corresponds to O-H bending vibration.…”

Development of a Novel Adsorbent Prepared from Dredging Sediment for Effective Removal of Dye in Aqueous Solutions

“…The porous properties of adsorbent were obtained by N2 adsorption-desorption technique using a Quadrasorb apparatus (Quantachrome, USA) at 77.35 K. The specific surface area (SBET) and volume of pore (VTotal) were calculated according to the Brunauer-Emmett-Teller method [18], and the pore size distribution was calculated by fitting the Barrett-Joyner-Hallender (BJH) model. The acidic-basic surface characteristics of the DSD adsorbent were studied according to the solid addition method as described by Rouahna et al (2020) [19]. A total of 50 mL of 0.01 M NaCl solution was kept in series of flasks (100 mL); the initial pH (pH0) of each sample was adjusted to a pH range of 3-11.…”