A comparative study of synthetic and natural coagulants for silver nanoparticles removal from wastewater

Abstract

A B S T R A C TUse of silver nanoparticles is increasing in different packaging material as disinfectant to protect food and pharmaceutical products. Its use has raised the contamination risk of fresh water and human exposure can cause serious problems. The coagulation/flocculation process can be an attractive option for silver nanoparticles removal at small-scale treatment just after its use. Four coagulants, aluminum sulfate, ferric chloride, Ocimum basilicum, and Hibiscus esculentus (synthetic and natural) were applied. For coagulation/flocculation activity, a series of jar test experiments were conducted to treat silver nanoparticles at concentration of 1 mg L −1 from wastewater. H. esculentus efficiently removed silver nanoparticles (98.7%) from aqueous solution at a dose of 150 mg L −1 , whereas at same coagulant dose, ferric chloride, O. basilicum, and aluminum sulfate successfully removed silver nanoparticles at 96, 69, and 50%, respectively. No broad change in pH was observed and it remained between 6.5 and 7.5 during all the experiments at room temperature.

Adsorption of Silver Nanoparticles from Aqueous Solution by Multiwalled Carbon Nanotubes

“…The present data revealed that the removal efficiency of AgNPs increase by increasing the amounts of MWCNTS (Table 1). This result was agreed with [42] who use four synthetic and natural coagulants as attractive option for AgNPs removal at small-scale, the authors observed that the removal percent of AgNPs increases with the increase in coagulant doses, and also in agreement with [43] Figure 3 and Table 2 Values within columns with no common superscript differ significantly (P ˂ 0.05). …”

Fast Procedure for Removing Silver Species in Waters Using a Simple Magnetic Nanomaterial

“…Many methods have been developed to remove silver nanoparticles, including the use of microorganisms and coagulation [20][21][22][23]. Various processes based on adsorption have been used for the removal of metallic nanoparticles, using materials such as chitosan [24], lignin [25], spent adsorbent [26], biochar [27,28], or biomass waste [29].…”

Occurrence and removal of engineered nanoparticles in drinking water treatment and wastewater treatment processes: A review

“…ENPs may bioaccumulate in important parts of the body, such as the brain, lungs, and/or liver, which can be harmful to health [5]. For example, Ag-NPs are likely to cause irreversible damage to the human body, such as changes in neurotransmitter levels and liver enzymes, and affect the human immune system [6].…”

“…As the knowledge on NPs becomes clear, methods for treating NPs in water (e.g., coagulation/flocculation/sedimentation, membrane filtration, adsorption, and oxidation) have been actively explored [5,[14][15][16]. For example, Jiang et al [15] found that the fluoroethylene fluoride microporous membrane is a new type of environmentally friendly industrial microporous membrane with a relatively low cost, exhibiting a ENP removal rate of up to 94.8%.…”