Evaluation of phosphate removal capacity of Fe3O4–ZVINPs from aqueous solution: optimization using response surface analysis

Abstract

The present research aims to optimize the removal of phosphate (PO 4 3-) from aqueous solution by Fe 3 O 4 stabilized zero-valent iron nanoparticles (Fe 3 O 4 -ZVINPs). A three-factor, three-level, Box-Behnken design combined with response surface methodology was applied to design the experiments, to develop a mathematical model, and for evaluating the individual and also the interactive effects of the operating variables like pH, temperature, and PO 4 3-concentration on removal efficiency. The analysis of variance has been used to evaluate the adequacy of the developed mathematical model in order to predict the optimal conditions of independent process variables, and to get maximum removal efficiency. Three-dimensional response surface plots were constructed to visualize the simultaneous interactive effects between two process variables. All three factors had a significant impact on removal of PO 4 3-. The predicted value of the model (166.0 mg g -1 PO 4 3-) was in good agreement with the experimental value (164.92 mg g -1 PO 4 3-) under the optimum conditions of temperature 49.2°C; pH 3.5; and PO 4 3-concentration 79.8 mg L -1 . The removal of PO 4 3-in the presence of environmental matrix (other ions) was also investigated at optimum conditions as predicted by the model. The results suggest that the presence of these ions had no significant effect on PO 4 3-removal. In addition, the adsorbed PO 4 3-can be effectively desorbed at higher pH of the solution. The findings suggest that removal of PO 4 3-from aqueous solution using Fe 3 O 4 -ZVINPs can be an effective method.

Synthesis, Biological Activity and QSAR Studies of Organotin(IV) and Organosilicon(IV) Complexes

“…The remaining compounds of series also found to be more susceptible as compared to the Gram negative bacteria, which may be due to the fact that the cell wall of Gram negative bacteria has more antigenic properties due to the presence of an outer lipid membrane of lipopolysaccharides. [37] In antifungal activity, compounds 10, 13, 14, 17 and 18 were found to be more active against A. niger and compounds 14, 17 and 18 against C. albicans. 4.…”

Optimization of phosphate removal from aqueous solution using activated carbon supported zero-valent iron nanoparticles: application of RSM approach

“…The three parameters known to have a significant effect on removal of phosphate such as temperature (T), solution pH and dose of AC/NZVI composite were selected as independent process variables and each them was at three levels. The highest, lowest and middle levels of the selected independent process variables were coded as 1, 0 and − 1, respectively (Singh and Singh 2016). Thus, on the basis of three-factor threelevel BBD, a total of 15 experimental set were produced using the following equation:…”

“…Quality and sustainability of aqueous streams is affected by eutrophication which is one of the severe problems worldwide. Reduction level of oxygen in an aqueous stream can be caused by eutrophication which rises environmental degradation and produces substantial financial effects on drinking water supplies and fisheries (Singh and Singh 2016). Thus, it is of great importance to develop simplest and efficient method in order to remediate the water contaminated with PO 4 3− .…”