Highly efficient mesoporous aluminium-magnetite-alginate magnetic composite for defluoridation of water

Abstract

One of the few elements that can have negative health impacts in both conditions, when consumed in excess or insufficiency is fluoride. In current study, aluminium magnetite alginate composite (AMA) was fabricated and applied using batch adsorption of fluoride as well as by using statistical modelling. Heterogeneous surface as revealed from scanning electron micrograph, thermal stability shown by thermal studies, high surface area of 29.77 m2 g-1, pore volume 0.1987 cm3 g-1 with mesoporous structure having average pore radius of 133 Å shown by BET analysis, fare degree of magnetization from VSM analysis were the important features of this material. Screening experiments and batch trials were carried out to obtain optimum working conditions. pH of 3.0, dosage of 50 mg, interaction period of 60 min and concentration of 50 mg L-1 depicted maximum defluoridation efficacy of about 94%. The adsorption capacity was found to be 60.08 mg g-1 in accordance with Langmuir adsorption isotherm, while pseudo second order kinetics was followed. Overall effects of various factors on sorption process were optimized using response surface methodology (RSM). Regeneration potential of AMA has been demonstrated for 10 adsorption-desorption cycles, showing more than 60% efficiency in tenth cycle. The AMA composite shows E-factor value 0.004 depicting it is sustainable in environment. In short, this novel composite showed excellent morphological, magnetic, functional properties that led to enhanced adsorption efficiency in short span of time that can be regenerated and reused in multiple cycles.