High capacity adsorption of malachite green in a mesoporous tyre‐derived activated carbon

Abstract

A mesoporous activated carbon derived from waste tyres was used to remove a toxic basic dye (malachite green oxalate, or MG) from aqueous solutions. The carbon contains a large volume fraction of mesopores and presents an excellent adsorption capacity of~424 mg/g towards MG, which is much higher than a commercial carbon with similar surface area. The adsorption equilibrium and kinetics were found to follow Langmuir equation and second-order kinetics, respectively. The structure of the carbon was characterised and based on which the dye adsorption mechanism was discussed.

Adsorption for Dyes on Activation Carbons from Japanese Cedar Wood Prepared by Precarbonization and Two-stage Composite Activations with Wood Ash and Steam

“…The adsorbance increased with pH value; as mentioned above, when the P200-0.25-750 was in a solution with pH 3-5, the zeta potential decreased from 0 to -23 mV, and it is inferred that the number of negatively charged active sites is increased [23], [37], thus, it is favorable for adsorbing cationic dye molecules. The adsorption of BG4 dye on P200-0.25-750, and the adsorption of malachite green dye on scrap tire ACs were identical with the result of the pH < 5 solution, meaning the solution hydrogen ion concentration is high and occupies partial adsorption sites, which is unfavorable for adsorbing malachite green dye [75]. The adsorption of BY2 dye on P200-0.25-750 is identical to the result of the adsorption of Auramine-O dye on ACs in the H 3-5 solution, and the dye adsorption quantity increases with the pH value [23].…”

“…According to the results, the BY2 and BG4 dyes adsorption quantity increased with the S BET and S ex of ACss other than K 2 CO 3 -1.00-800 (Table II), because the developed mesopores' structure is connected to the micropore channel, which is favorable for the adsorption result of ACs [70]. However, the K 2 CO 3 -1.00-800 had high S BET 1537 m 2 /g and S ex 1162 m 2 /g, but less micropores (V mi 0.16 cm 3 /g, V mi /V tot 18.6%, Table II), meaning it is disadvantage to adsorbing micro-molecular adsorbate [21], [23], [37], [49], [71]- [75].…”

Effect of pyrolysis conditions on the improvement of the physicochemical structure of activated carbon obtained from Jixi bituminous coal

“…These results indicate that it is difficult to obtain ideal AC production only by adjusting the activation condition; thus, the key factor is the improvement of the physicochemical structure of the coal char at the pyrolysis stage. More initial pores can rapidly promote the diffusion of the activated gas into the interior of the particles to avoid external loss of quality, and many active sites can promote the reaction between the activation agent and carbon matrix to produce more micropores and mesopores …”

Economic pre‐feasibility study for physical conversion of polyethylene terephthalate wastes to activated carbon

“…They also have good applications in gas purification, solvent recovery, and waste water treatment. [3,[13][14][15][16][17][18][19] In this study, the process of activated carbon production from PET wastes involving carbonization and activation furnaces was simulated using Aspen Plus 7.2 software. Based on the simulated data and the equipment cost calculations, a comprehensive economic feasibility study has been carried out using Aspen Process Economic Analyzer 7.2 software.…”

“…Carbon adsorbents have low cost, are recyclable, and so popular that they exhibit excellent properties in gas separation as well as in environmentally toxic waste separation because of their porous structure. They also have good applications in gas purification, solvent recovery, and waste water treatment …”