Dyes Adsorption by Nanomaterials: Fixed-Bed Column Studies Using Nano Magnesium Oxide-Loaded Activated Carbon

Abstract

Rapidremoval rates with high pollutantbinding strength allow nanostructured materials ideal for dyes adsorption. In this analysis, methylene blue (MB) column adsorption experiments were performed using nano-MgO-loaded activated carbon (n-MgO/AC). The synthesized n-MgO/AC adsorbent was adequately characterized by several analytical methods. The potential effect of variables on the adsorption of columns, that is, MB flow rate, n-MgO/AC 260bed height, and MB inlet concentration was examined in-depth. Usually, with an improvement in MB flow rate (4–12 mL/min), n-MgO/AC bed height (2.5–7.5 cm) and MB concentration (20–60 mg/L) decrease in break time from 210 to 30 min, improvement from 210 to 720 min and decrease from 390 to 60 min, respectively. For forecasting breakthrough curves, the experimental results under different operating conditions were fitted with models, such as Thomas, modified dose–response/Yan, and Bed-depth service time (BDST). Breakthrough time, MB percent removal, the zone of mass transfer (MTZ), the empty contact time of the bed (EBCT), and dye uptake (qexp ) were reported. The compatibility of the experimental results with the dynamic mathematical models indicates the suitability of these models in a breakthrough curve prediction. After three cycles of adsorption– desorption, the n-MgO/AC adsorbent regeneration studies showed almost 80% regeneration efficiency. Hence, the potentiality of the n-MgO/AC composite as adsorbent was confirmed.