Comparison of methylene blue removal efficiency of activated carbon and carbon nanosheets derived from olive stone from aquatic environment

In recent years, the increase in population growth and the rapid development of industries have given way to a rise in the usage of natural resources and waste production. Solid waste management (SWM) is an essential component of an environmental management system. SWM approaches are being adapted to make them more practical and effective by environmental regulations and to promote sustainability through the application of the “reduce”, “reuse”, and “recycle” (3R) principles. Therefore, the present study focuses on the reuse of waste as an adsorbent agent with a low cost for removing methylene blue. To achieve such feat, olive stones were milled, pyrolyzed, and sonicated to synthesize activated carbon and carbon nanosheets. Additionally, the study investigated the impact of five parameters (dose of adsorbent, pH, primary pollutant concentration, and temperature) on the adsorption process. FESEM and TEM analyses were carried out in order to make clear what the characteristics of the adsorbent were. The isotherm assessments show that the data is quite fitting for the Langmuir model for adsorption by activated carbon and carbon nanosheets. Additionally, the adsorbent obtained through kinetic modeling indicate that the experimental data is well-matched by the pseudo-second-order kinetic model for activated carbon and carbon nanosheets. Synthesized activated carbon and carbon nanosheets from olive stones are low-cost adsorbents with good adsorption properties. They reduce solid waste generation and are efficient adsorbents when it comes to removing methylene blue that is present in aquatic environments.