Synthesis and characterization of zero-valent iron nanocomposites based on granular activated carbon using walnut leaf extract reducer
Volume Title: 1
Authors
1Faculty Member of Mohaghegh Ardabili University
2Student of Mohaghegh Ardabili University
3Mohaghegh Ardabili Universit
Abstract
Nanoscale zero-valent iron (nZVI) is one of the most effective materials recently used to remove heavy metals from water. However, their tendency to aggregation and rapid oxidation reaction is one of the major drawbacks reported in the literature. In other words, the rapid reduction of impurities, especially cations in water, is an important feature of zero valent iron. In order to revive iron particles during synthesis, sodium borohydride is usually used to as a strong reducer. Due to the problems of this chemical matter, green synthesis method was used in this study. Walnut leaf extract is capable of easily reducing iron cation to zero-valent iron due to its polyphenolic materials. Therefore, in this study, nZVI particles were produced using walnut leaf extract as a green reducer and stabilizer. Then nZVI particles were stabilized on the granular activated carbon (WL-nZVI/GAC). The characteristics of WL-nZVI/GAC synthesized by (FE-SEM) and (FTIR) were studied. The main purpose of the production of this nanocomposite is to remove heavy metals present in contaminated water and wastewater. Also, in this study, the isoelectric point of the nanocomposite was investigated. The results showed that the size of the produced iron nanoparticles was about 16.72-27.77 nm. It can be seen from the FTIR spectrum that the polyphenols present in walnut leaf extract are responsible for the formation of WL-nZVI/GAC. The pH at the zero charge point (pHPZC) is 6.1-6.2, indicating that the adsorbent level of WL-nZVI/GAC at pH lower than pHPZC positive and at pH higher than pHPZC negative.
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