Different techniques for enhancing the removal of methylene blue (MB)‎ dye from aqueous solution

Abstract EN

Different techniques were conducted for removal of MB dye from aqueous solution.

These techniques which were used separately are: (i) adsorption using activated carbon (AC) prepared from composite of different ratios of Date Pits-Clay (DP-C); (ii) Chemical oxidation using H2O2; and (iii) photo degradation using UV irradiation.

In the adsorption technique, a series of experiments were undertaken in an agitated batch to assess the effect of the system variables; types of activated carbon, pH, adsorbent and adsorbate concentration, temperature and interfering ions.

From the isotherm studies, the Langmuir monolayer capacity was 416.67 mg/g.

The kinetic parameters have shown that they could be fitted well to the pseudo-second-order kinetic and intra-particle diffusion models.

The temperature study showed that the MB adsorption is endothermic and spontaneous with increased randomness at the solid solution interface.

The presence of interfering ions has an insignificant effect with the exception of Cl- anion that slightly decreases the adsorption of MB.

Finally, the addition of H2O2 and UV irradiation in the presence AC enhances the removal of MB dye.

The rates of the second order for the removal of MB dye take the following order: AC+H2O2+UV > AC+UV >AC+H2O2 > AC.