الفهرس 
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Abstract
The aim of this study is the preparation of activated carbon from Ficus nitida and to use as an adsorbent to remove methylene blue (MB) decontamination from polluted wastewater. Ficus nitida activated carbon was prepared by thermal activation of ficus nitida (leaves) at different conditions such as activation temperature (400,500,600,700,800 and 900°C) and activation time (0.5, 1, 2 and 3 hours) and 24 samples were prepared of activated carbon.
The physical and chemical characteristics of raw ficus nitida and activated carbon with high efficiency (activation temperature 900°C, activation time 0.5 h) were examined using different techniques such as scanning electron microscopic (SEM), Fourier Transform Infrared Spectrometer (FTIR) and BET surface area.
The various factors affecting the treatment of methylene blue (MB) onto the most efficient activated carbon were studied such as: 1. pH (2,5,6,7 and 9) 2. Temperature (25,35,45 and 55°C) 3. Adsorbent dose (0.4,0.6,0.8,1 and 1.2) gram/lit 4. Initial dye concentration (10,30,50,70 and 100) ppm
The experimental results showed that the adsorptive removal of dye increased with increasing the temperature, adsorbent dose and decreased with increasing the initial dye concentration. The optimum pH found after adsorption experiments was pH = 6.
The equilibrium time for dye sorption process onto the prepared activated carbon was established at 3 hours. The experimental work was modeled using different equilibrium and kinetic models. Adsorption studies showed that the adsorption followed Langmuir isotherm. Kinetic studies showed that the adsorption followed pseudo-second-order reaction.
Thermodynamics parameters of adsorption process were also determined in this study. The positive value of ∆H indicates that the adsorption of MB is an endothermic reaction. The negative value of ∆G indicates spontaneous nature of the adsorption process for low concentration (10 and 30 ppm) and for higher concentration (50, 70 and 100 ppm) ∆G has positive value which indicates non spontaneous. Further the positive value of entropy change ∆S shows the increased randomness at the solid/liquid interface of FNAC for MB dye.
The Ficus nitida was established to be suitable resource for the preparation of activated carbon and could be used as an adsorbent to remove of methylene blue (MB) from polluted wastewater.