Evaluation of Cationic Methylene Blue Dye Removal by High Surface Area Mesoporous Activated Carbon Derived from Ulva lactuca

Mesoporous nano-activated carbon was prepared from green algae Ulva lactuca using zinc chloride impregnation as the activation process. The obtained activated carbon was tested as a cationic dye adsorbent which is the aim of this research work. Prepared activated carbon was characterized by FTIR, BET, t-plot, BJH, TGA, SEM, TEM and EDAX. The obtained activated carbon has 84.37% carbon content, 1486 m 2 /g specific surface area, 0.8891 cm 3 /g total pore volume, and 2.32 nm average pore diameter. The adsorption properties of the prepared activated carbon were tested using Methylene blue (MB) dye. Batch experiments were applied under different adsorption parameters like pH, adsorbent dose, initial MB dye concentration, and agitation time. Different known isotherms and kinetics models were applied to the batch experimental data of MB dye removal. It was found that the adsorption data was well fitted by Langmuir model showing a monolayer adsorption capacity of 344.83 mg/g of MB dye. Kinetic studies revealed that the MB dye adsorption by Ulva lactuca activated carbon followed pseudo-second-order model with very high correlation coefficient ( R 2 > 0.998). The prepared activated carbon was subjected to a total of five adsorption-desorption regeneration cycles with very small loss of its dye-adsorption capacities.