Iranian Research Organization for Science and Technology Advances in Environmental Technology 2476-6674 2 3 2017 04 22 Desorption of Reactive Red 198 from activated carbon prepared from walnut shells: effects of temperature, sodium carbonate concentration and organic solvent dose 137 141 432 10.22104/aet.2017.432 EN Zohreh Alimohamadi Department of Environmental Science, Faculty of Natural Resources, Tarbiat Modares University, Noor, Iran Habibollah Younesi Department of Environmental Science, Faculty of Natural Resources, Tarbiat Modares University, Noor, Iran Nader Bahramifar Department of Environmental Science, Faculty of Natural Resources, Tarbiat Modares University, Noor, Iran Journal Article 2016 06 18 <span>This study investigated the effect of temperature, different concentrations of sodium carbonate,and the </span><span>dose<span class="hps"> of organic solvent on the </span></span><span>desorption of Reactive Red 198 dye from </span><span>dye-saturated activated carbon</span><span> using batch and </span><span>continuous systems. The results of the batch desorption test showed 60% acetone in water</span><span> as the optimum amount.</span><span> However, when the concentration of </span><span>sodium</span><span> carbonate was raised,</span><span> the</span><span> dye </span><span>desorption percentage increased from 26% to 42% due to economic considerations; 15 mg/L of sodium carbonate </span><span class="hps"><span>was selected to continue the process</span></span><span class="hps"><span>of desorption.</span></span><span> Increasing the desorption temperature can improve the dye desorption efficiency.</span><span>According to the column test results, </span><span class="hps"><span>dye desorption concentration </span></span><span>decreased gradually with the <span class="hps">passing of time. </span></span><span>The column test results showed that </span><span>desorption efficiency</span><span> and the percentage of </span><span>dye adsorbed </span><span>decreased; however, it seemed to stabilize after three repeated adsorption/desorption cycles. </span><span class="hps"><span>The </span></span><span>repeated adsorption–desorption column tests (3 cycles) showed that the </span><span>activated carbon which was prepared</span><span> from walnut shell</span><span> was a </span><span>suitable and economical adsorbent for dye removal.</span> https://aet.irost.ir/article_432_248e844336797ec98478f85e7626de4a.pdf