Effective Parameters, Equilibrium, and Kinetics of Fluoride Adsorption on Prosopis cineraria and Syzygium cumini Leaves

Abstract

This study was designed to present a facile and effective biosorbent from Prosopis cineraria and Syzygium cumini leave (PCL and SCL) for fluoride removal. The test was done in batch mode and the effect of contact time (5, 25, 60, 90, and 120 min), initial fluoride concentration level (3, 5, 8, and 12 mg/L), and biosorbent dose (1, 3, 5, 10, and 25 g/L) on the biosorption process were examined. The optimum conditions for the maximum fluoride removal were occurred at 1 g/L biosorbent dose and contact time of 120 (for PCL) and 90 min (for SCL). The results suggested that the pseudo‐second‐order and Langmuir isotherm models described the experimental data well. According to the Langmuir model, the maximum adsorption capacity of fluoride for PCL and SCL was attained 11.52 and 7.4 mg/g, respectively. Based on Boyd and intra‐diffusion models, the biosorption of fluoride onto PCL and SCL was mainly controlled by film‐diffusion. The study revealed the potential use of PCL and SCL as two new effective biosorbents for the removal of fluoride from aqueous solution. © 2019 American Institute of Chemical Engineers Environ Prog, 38: S429–S440, 2019

Fluoride removal from drinking water (Metlaoui, Tunisia) using untreated and treated natural clays

“…Keshtkar et al . investigated the fluoride removal efficiency by increasing the dose of Prosopis cineraria leaves from 1 to 25 g L −1 20 . Fluoride removal increased with the adsorbent dose from 1 to 10 g L −1 followed by a plateau.…”

“…In recent years, several efforts have been made in order to develop practical adsorbents. Modified pumice, 14 Moringa oleifera seed ash, 15 Padina sanctae‐crucis algae, 16 cuttlebone, 17 bauxite, 18 decyltrimethylammonium bromide/H 2 O 2 solution‐treated organic matter‐rich clay, 19 Prosopis cineraria and Syzygium cumini leaves, 20 MgFe 2 O 4 –chitosan–CaAl composite, 13 washed and dried montmorillonite 4 and three‐dimensional porous Ca‐modified Mg–Zr mixed metal oxides 21 are some of the adsorbents investigated. A major difficulty in achieving high percentages of fluoride removal is the need to modify water pH which has outcomes for potability 12 .…”

Biosorption of fluoride from aqueous solutions by Rhizopus oryzae: Isotherm and kinetic evaluation

“…This model assumed that the amount of change in the solute content over time is logarithmically proportional to changes in the saturation concentration and the content of biosorbent over time. 39 The pseudo-second-order supposed that the sorption process can be controlled by chemical biosorption. 39 Elovich kinetic model assumes that the active sites of biosorption surface are energetically heterogenous in nature; therefore it is one of the important models for describing the chemisorption process.…”

“…39 The pseudo-second-order supposed that the sorption process can be controlled by chemical biosorption. 39 Elovich kinetic model assumes that the active sites of biosorption surface are energetically heterogenous in nature; therefore it is one of the important models for describing the chemisorption process. 59 The biosorption process follows three ordinal steps:…”

“…27,[32][33][34] Biosorption method has many advantages such as low operating cost, minimization the quantity of chemical or biological sludge, no nutrient requirements, environmentally favorable properties, and regeneration of biosorbent. 35,36 Different biosorbents have been prepared from various microbial sources, 37 leaf based sorbents, 25,38,39 algae, [40][41][42] and fungi 35,43 for fluoride removal from aqueous solution with different degrees of success. Therefore, the researchers' try to explore and develop new adsorbent that can improve the efficiency of fluoride removal and provide unique material for an adequate sorption capacity.…”