Evaluation of methylene blue adsorption properties
Absorption properties and the removal efficiency of MXene/AAC hybrids was conducted and calculated by detecting the adsorbent dosage, initial pH and initial concentration of methylene blue in the aqueous solution. The aqueous liquid was methylene blue-water solution with the concentration of methylene blue ranging from 50 mg/L to 2000 mg/L. For each adsorption experiment, 10 mg MXene/AAC adsorbent was added into a 50 mL methylene blue solution and then ultrasonic-dispersed to form an even and stable solution. The mixtures were oscillated at room temperature for appropriate time intervals ranging from 10 min to 48 h to calculate the kinetic adsorption. After that, the mixture was filtered to remove the residual adsorbent and the methylene blue concentration of the dilute solution was analyzed30. The adsorption capacity qe (mg/g) was calculated by using the following equation:
\(q_{e}=\frac{(C_{0}-C_{r})\times V}{1000m}\) (1)
The adsorption percentage is calculated as followed equation:
\(\text{Removel\ }\left(\%\right)=\frac{(C_{0}-C_{r})}{C_{0}}\times 100\)(2)
Where C0 and Cr are the initial and residual concentrations (mg/L) methylene blue, respectively;V is the solution volume (ml); and m (g) is the adsorbent weight (g).
To confirm the optimum mass of MXene/AAC for maximum removal of methylene blue from the mixture solution, different weight of MXene/AAC hybrids ranging from 5 to 100 mg were tested. All the samples were oscillated at room temperature. To study the effect pH on the removal efficiency of methylene blue, a series of experiments were conducted at different pH values ranging from 2-12 by adjusting with HCl or NaOH. The adsorption performance of the adsorbent regenerated from 1-3 desorption recycles were evaluated, respectively.