Synthesis of Highly Monodispersed, Stable, and Spherical NZVI of 20–30 nm on Filter Paper for the Removal of Phosphate from Wastewater: Batch and Column Study

Abstract

A nanobiodegradable adsorbent was prepared by stabilizing nanoscale zerovalent iron (NZVI) on cellulose filter paper. Characterization of the sample disclosed that the NZVI particles were rounded, well-monodispersed through the paper, and smaller than 30 nm in diameter. We explored this material's ability to capture phosphate ions in batch and repeated operations, specifically studying the impact of pH, adsorption time, initial phosphate concentration, interference ions, and temperature. The equilibrium results were matched to dissimilar kinds of adsorption isotherms, with the Sips adsorption model displaying the best match. The stabilized NZVI indicated high reusability after 7 adsorption−desorption cycles. We also demonstrated how this nanobiodegradable adsorbent could be applied to eliminate phosphate ions from a real water source (Cayuga Lake). In the continuous system, the results confirmed that an enhancement in the initial phosphate ion concentration improved the phosphate removal ability of the filter-paper-stabilized NZVI, likely due to more motive power for mass transfer by the greater phosphate concentration. However, an enhancement in bed height and flow rate reduced phosphate removal because of the higher flow rate decreasing the reaction time of the solution and adsorbent, whereas the higher bed height resulted in a channeling effect. Breakthrough curves gained from fixed-bed column tests showed the strong potential of the NZVI for phosphate ion sequestration. An artificial neural network model was used to envision the phosphate ions removal in both batch and continuous systems by this composite. The adsorption mechanism of phosphate onto the filter-paperstabilized NZVI was further investigated by X-ray spectroscopy, X-ray diffraction, elemental mapping, and zeta potential techniques.

Interpenetrating network gelatin methacryloyl (GelMA) and pectin-g-PCL hydrogels with tunable properties for tissue engineering

“…Spectra were recorded in the range of 4000-400 cm −1 using KBr pellets. 45 Differential scanning calorimetry. Samples were heated from 30°C to 275°C under 70 ml min −1 inert N 2 gas at a heating rate of 10°C min −1 using a Netzch 204 F1 Phoenix DSC equipped with an intra-cooler system.…”

Sonochemically Synthesized Ultrastable High Internal Phase Emulsions via a Permanent Interfacial Layer

“…To obtain scanning electron microscopy (SEM) images, HIPEs were placed onto a silicon wafer, freezedried, and sputtered with gold. 21 The porous structures of the HIPEs were observed on a LEO 1550 SEM equipped with a GEMINI field emission column. The morphology of the fresh HIPEs was characterized by cryo-SEM.…”

The gorgeous transformation of paper: from cellulose paper to inorganic paper to 2D paper materials with multifunctional properties

“…Nanoscale zero valent iron (NZVI) as a nano-adsorbent is used for water remediation, but its easy aggregation leads limits it reactivity and stability. 89 Benefiting from the biocompatibility and porosity of cellulose paper, Arshadi et al 90 reported the preparation of NZVI monodispersed filter paper for the sequestration of phosphate ions from wastewater. The resulting paper displayed a remarkable phosphate removal efficiency of 99.9% for certain phosphate ion amounts and contact times and exhibited high reusability after 7 adsorption–desorption cycles.…”