Influence of alternating current on the adsorption of indigo carmine

Abstract

The main purpose of this work is to study the effect of a new process of accelerating which consist to couple the electrochemical process with the adsorption to remove an anionic dye, the indigo carmine. That is why, we investigated the effects of the new process of accelerating the adsorption process by using alternating current (AC) on the retention of an anionic dye, the indigo carmine. The adsorption capacity of dye (mg/g) was raised with the raise of current voltage in solution, temperature, and initial indigo carmine concentration and decreased with the increase of initial solution pH, current density, and mass of carbon. The results demonstrate that the removal efficiency of 97.0 % with the current voltage of 15 V is achieved at a current density of 0.014 A/cm, of pH 2 using zinc as electrodes and contact time of 210 min for adsorption in the presence of AC. Concerning the adsorption without AC, the results obtained showed that for an initial concentration equal to 20 mg/L, more than 95 % amount of adsorbed dye was retained after 405 min of contact in batch system. The comparison between adsorption in the presence and absence of an alternating current shows the importance of the alternating current in the acceleration of the adsorption method and improve the performances of FILTRASORB 200. For both cases, the adsorption mechanism follows the fractal kinetics BSf(n,α) model and the Brouers-Sotolongo isotherm model provides a good fit of the experimental data for both adsorption with and without alternating current.

Hydrothermal pre-treatment, an efficient tool to improve activated carbon performances

“…was also confirmed by the values of the "fractional times" α, which were always lower than 1, in agreement with previous results (Kesraoui et al, 2017;Selmi et al, 2018c). When the concentration increased from 10 to 100 mg/L, the fractality increased as well, as suggested by the decrease of the values of α from 0.614 to 0.49, again in agreement with former studies (Selmi et al, 2018b).…”

Dynamics and Kinetics of Cupric Ion Removal from Wastewaters by Tunisian Solid Crude Olive-Oil Waste

“…Using the parameters of the Broeurs-Sotolongo model (γ, n and τ), the half sorption time (τ 50% ) can be determined according to the following equation [48,49]:τ50%=sans-serifτ(2(normaln−1)−(normaln−1)(normaln−1))1/sans-serifγ…”

Production of modified sunflowers seed shells for the removal of bisphenol A

“…32,35,65 The parameter a describes the fractal properties of a non-uniform system and its adsorption mechanisms. 35,65,66 While the parameter c is related to the agglomeration on the adsorbent surface, it gives an idea of the degree of heterogeneity of the adsorbent surface. Furthermore, it has been shown that an increase in the c value indicates a decrease in surface heterogeneity or the opposite.…”