Low-Cost Synthesis of Alumina Nanoparticles and Their Usage for Bisphenol-A Removal from Aqueous Solutions

Abstract

Gamma-alumina nanoparticles (γANPs) were obtained from a low-cost process by using natural bauxites. The γANPs materials were characterized by X-ray powder diffraction (XRPD), Fourier-transform infrared spectroscopy (FTIR), Brunauer–Emmett–Teller (BET) theory, scanning electron microscopy (SEM), atomic force microscopy (AFM), and were functionalized with N-cetyl-N, N, N, trimethylammonium bromide (CTAB), leading to CTAB modified γ-alumina nanoparticles (γANPs-CTAB). These novel functionalized γANPs-CTAB were characterized by XRPD, FTIR, and were used as an adsorbent for bisphenol-A (BPA) removal from water. Batch investigations were conducted under different experimental conditions (e.g., adsorbent dose, agitation time, initial concentration, and pH and surfactant loading) in order to optimize BPA adsorption and to identify the adsorption mechanisms in the system γANPs-CTAB-BPA. The effect of pH on the adsorption showed that the quantity of BPA removed increased remarkably until the pH value was 4, then remained almost constant until the pH value was up to 10, and then decreased for pH values greater than 10. For an initial BPA concentration of 20 mg/L and an adsorbent dose of 12.5 g/L at a pH value of 10, the removal efficiency achieved was 91.80 ± 0.21%. The adsorption mechanism was perfectly described by pseudo-second-order kinetics and the Langmuir isotherm. γANPs-CTAB materials were found to be effective adsorbents for BPA removal from water.

Removal of Thallium from Aqueous Solutions by Adsorption onto Alumina Nanoparticles

“…It is worth noting that nowadays, research efforts are currently focusing on the production of gamma-alumina nanoparticles with controlled porosity at the nanometer scale, the objective being to obtain materials with suitable properties for the elimination of pollutants up to the trace state. Recently, in an attempt to boost the additional value of natural local bauxites, they were used as precursors in the synthesis of low-cost gamma-alumina nanoparticles (γANPs) [67]. The γANPs were subsequently functionalized with CTAB and the physicochemical properties of the CTAB-functionalized γANPs (γANPs-CTAB) were investigated in view of bisphenol-A removal [67].…”

“…Recently, in an attempt to boost the additional value of natural local bauxites, they were used as precursors in the synthesis of low-cost gamma-alumina nanoparticles (γANPs) [67]. The γANPs were subsequently functionalized with CTAB and the physicochemical properties of the CTAB-functionalized γANPs (γANPs-CTAB) were investigated in view of bisphenol-A removal [67]. Indeed, the quest for simple, low-cost, and high-performance water purification processes in developing countries requires the use of local materials that are natural materials, good sorbents, inexpensive, and represent a viable replacement for high-cost starting materials and toxic precursors that are involved in synthesis processes.…”

“…In our context, large deposits of bauxite ores are widely available in the Center-North region of Burkina Faso. Bauxite is a raw material which is well known as the best source of aluminum for the synthesis of nano gamma-alumina powder [67]. In this regard, specific attention has been drawn to the low-cost synthesis of gamma-alumina nanoparticles for pollutants removal from aqueous solutions [67].…”

“…Bauxite is a raw material which is well known as the best source of aluminum for the synthesis of nano gamma-alumina powder [67]. In this regard, specific attention has been drawn to the low-cost synthesis of gamma-alumina nanoparticles for pollutants removal from aqueous solutions [67]. However, to the best of our knowledge, gamma-alumina nanoparticles-synthesized from natural local bauxites-have not yet been used for the interaction with thallium (I) ions.…”