Comparison of Paraquat Herbicide Removal from Aqueous Solutions using Nanoscale Zero-Valent Iron-Pumice/Diatomite Composites

<table class="table-group" id="tab1"><tr><td><table class="table"><tr><td class="thead-hr" colspan="9"><hr/></td></tr><tr class="thead"><td class="align_left">Model</td><td class="align_center" colspan="4">Langmuir</td><td class="align_center" colspan="4">Freundlich</td></tr><tr class="thead"><td class="align_left">Equation</td><td class="align_center" colspan="4"><span style="width: 153.913ptpx;"><svg height="12.7178pt" id="M9" style="vertical-align:-3.42947pt" version="1.1" viewbox="-0.0498162 -9.28833 153.913 12.7178" width="153.913pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M300 -147C201 -63 143 98 143 270S200 602 300 686L282 710C136 610 70 450 70 271V270C70 89 136 -72 282 -170L300 -147Z"></path></g><g transform="matrix(.013,0,0,-0.013,4.498,0)"><path d="M645 631C614 643 545 666 457 666C215 666 23 519 23 283C23 90 158 -16 337 -16C412 -16 489 2 522 10C543 39 590 127 606 167L580 181C519 89 459 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colspan="2"><i>K</i><sub><i>f</i></sub>[(mg·g<sup>−1</sup>) (L·mg<sup>−1</sup>)<sup>1/<i>n</i></sup>]</td></tr><tr><td class="thead-hr" colspan="9"><hr/></td></tr><tr><td class="align_left">Absorbent</td><td class="align_center">D-nZVI</td><td class="align_center">P-nZVI</td><td class="align_center">D-nZVI</td><td class="align_center">P-nZVI</td><td class="align_center">D-nZVI</td><td class="align_center">P-nZVI</td><td class="align_center">D-nZVI</td><td class="align_center">P-nZVI</td></tr><tr><td class="align_left">Amount</td><td class="align_center">161.3</td><td class="align_center">169.4915</td><td class="align_center">0.99</td><td class="align_center">0.02</td><td class="align_center">0.3699</td><td class="align_center">0.4225</td><td class="align_center">22.75</td><td class="align_center">15.04</td></tr><tr class="table-tr"><td colspan="9"><hr class="tbody-hr"/></td></tr></table></td></tr></table>

<div>Calculated parameters of the Langmuir–Freundlich model for D-nZVI and P-nZVI adsorbent.</div>

International Journal of Chemical Engineering

tab1

Table 1

Table 1: Comparison of Paraquat Herbicide Removal from Aqueous Solutions using Nanoscale Zero-Valent Iron-Pumice/Diatomite Composites 