Optimization of fluoride adsorption from aqueous solution over mesoporous titania‐alumina composites using Taguchi method

Abstract

The optimization of fluoride removal from aqueous media was studied over the mesoporous titania‐alumina composites using Taguchi method‐based L25 orthogonal array experimental design. The chemical structure, surface chemistry, and morphology of as‐prepared composite adsorbents were studied utilizing various analytical methods. The findings of the characterization demonstrated that the produced composites have high textural qualities, which are conducive to enhanced fluoride adsorption. The optimum conditions for maximum percentage removal of fluoride from aqueous solution were found as adsorbent type as TA75, adsorbent dose 4 g L−1, initial concentration of fluoride 40 ppm, solution pH 3 with a treatment time of 60 min. Under the optimum conditions, 98% of fluoride adsorption was achieved. Analysis of variance revealed that the solution pH followed by the adsorbent dose was the most significant for fluoride adsorption. The Langmuir model and pseudo‐second‐order kinetic model fit the adsorption data well, and the TA75 adsorbent had a maximum Langmuir fluoride adsorption capacity of 34.48 mg g−1 at pH = 3. The thermodynamic information suggests that the adsorption was spontaneous and endothermic under the given operating conditions. The synergic combination of Ti–Al nanoparticles demonstrated a high percentage removal of fluoride under the optimized operating conditions. Practitioner Points The Taguchi method‐based design of the experimental approach was implemented in the fluoride adsorption process. Mesoporous titania‐alumina composites with 0 to 100 wt.% of alumina in titania were prepared and applied to remove fluoride from an aqueous solution. Solution pH was the most influential parameter for the fluoride adsorption process, while the synergistic combination of 75 wt.% alumina in titania showed the maximum adsorption capacity.

The Constructing of the Oxide Phase Diagram for Fluoride Adsorption on La-Fe-Al: A Collaborative Study of Density Functional Calculation and Experimentation

“…ln q e = ln q max − βε 2 (10) where q max is the maximum simulated saturated adsorption capacity (mg/g) and b is Langmuir's constant. In the Freundlich equation, K F (mg 1−(1/n) L 1/n g −1 ) and n are Freundlich constants related to adsorption capacity and adsorption strength.…”

“…Nevertheless, the release of wastewater from metallurgical and semiconductor industries, the natural degradation of fluoride-containing minerals, and the application of pesticides and fertilizers in agricultural production can lead to fluoride contamination in water bodies [3][4][5][6]. According to relevant studies, the water environment of most countries in the Americas, Asia, and Africa has serious fluoride pollution [7][8][9][10], posing a serious threat to human health. The World Health Organization limits the maximum amount of fluoride ions in drinking water to 1.5 mg/L to avoid the harm caused by fluoride in water [11,12].…”