Seawater Reinforces Synthesis of Mesoporous and Microporous Zeolites from Egyptian Fly Ash for Removal Ions of Cadmium, Iron, Nickel, and Lead from Artificially Contaminated Water

Abstract

This study focuses on the production of mesoporous and microporous zeolites via fusion pre-treating fly ash with NaOH followed by hydrothermal treatment utilizing seawater. Three pretreatments for fly ash were carried out utilizing 1:1, 1.2:1, and 1.4:1 of NaOH:fly ash ratio to compare the removal efficiency for cadmium Cd(II), iron Fe(II), nickel Ni(II), and lead Pb(II) from artificially contaminated water. The impacts of several variables including concentrations, weights, pH, and contact times were examined to acquire knowledge on the adsorption rate. X-Ray Diffraction (XRD), Scanning Electron Microscope (SEM), and Brunaauer-Emmett-Teller (BET) were utilized to investigate zeolite structures. N2 adsorption/desorption isotherms demonstrated that the synthetic zeolites were mesoporous and microporous materials with a higher specific area (347, 240, and 127 m 2 /g) than the values for raw fly ash (15m 2 /g). The X-ray diffraction outcome suggested that the synthetic products mainly belonged to phillipsite, carbonate cancrinite, and hydroxysodalite. These outcomes showed that fly ash and seawater from power plants are appropriate for synthesizing high-quality zeolites. For contaminated water treatment, the products are effective for removal Cd(II), Fe(II), Ni(II), and Pb(II) at pH 7, contact time 45 min, and dose 1 g/L. Zeolites recycling outcomes showed that the removal efficiency of investigated metal ions by Z1, Z2, and Z3 was reduced by an average of 7%, 5%, and 3% after regeneration.

Comparative study for removal of phosphorus from aqueous solution by natural and activated bentonite

“…The bigger issue in wastewater treatment is the regeneration of the adsorbent materials. Regeneration is an alternative to disposal for spent both adsorbents 8 , 64 . The regeneration process is removing the pollutants from the spent natural and Na-bentonite, after cycles (3 trials) of repeated reuse of adsorbents for adsorption/desorption in the treatment.…”

Simultaneous Removal of Metal Ions from Wastewater by a Greener Approach

“…Each trial had three repetitions, the results were averaged, and the standard deviation (STD) was calculated. The removal efficiency (RE%) and the adsorption capacity (qe, mg/g) were estimated by Equations ( 1) and (2), in which V is the volume (L) of the solution, and W is the mass (g) of biosorbent [18,51].…”

“…On the other hand, it was proved that the competitive outcomes of the biosorption of metals by S. cerevisiae followed the order: Pb(II) > Cd(II) > Ni(II). Because lead has a smaller ionic cation radius (4.01 for lead [18]), it has a higher probability of being biosorbed by S. cerevisiae than the other metal ions. For a single metal at 25 mg/L, simulated solutions of the efficacy of the removal of Ni(II) and Cd(II) were viewed at 60 and 80%, respectively, and almost 99% for Pb(II), as discussed previously in that investigation, while in food effluent, the efficacy of elimination by S. cerevisiae was almost 100% for Pb(II), Cd(II), and Ni(II).…”

“…Adsorption, in any case, remains a feasible alternative, particularly in developing nations, since it is environmentally benign, simple, inexpensive, and does not produce large sludge quantities [11,12]. In recent decades, various natural and manufactured adsorbents have been examined for their ability to eliminate heavy metals from contaminated solutions [13][14][15][16][17][18][19][20]; however, separating these adsorbents from the aqueous solution entails a complex process with additional costs, and structure stability should be emphasized [20].…”

Synthesis of Zeolite Beta Using Seawater Instead of Deionized Water

“…Up to now, only a few papers report the use of seawater during the hydrothermal synthesis of artificial zeolite from fly ash [7][8][9][10] and volcanic ash [11] as a source of silica and alumina. The synthesizing process for zeolite from these materials requires an alkaline treatment using NaOH at high temperatures to assure the conversion of the fly ash and volcanic ash into zeolite.…”