الفهرس 
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Abstract
The use of dyes in industries like dying, textile, cosmetics, printing, papermaking, and food coloring can cause colored effluents. Discharging of dyes into water resources which are very toxic even in a small amount can cause serious ecological problems. In the last few years, the removal of dyes from industrial effluents has been given much more attention, not only because of their potential toxicity but also due to their damaging nature to the environment. The removal of color from textile wastewater is a significant environmental problem because of the difficulty of treating such waters by conventional methods. Therefore, dye removal has been a very important but challenging research area of wastewater treatment. Adsorption which is the most economical and effective has become the most preferred method for the dyes removal.
In this study, some wastes of date palm (leaves and trunks) have been collected from Borg el-Arab at Alexandria and Rashed at el-Beharia., washing with distilled water and let it to dry in the sun then cutting and milling with grinding machine to be used for the removal of the Acid Red 8 (AR8) dye from aqueous medium.
Particle size analyzer was used to determine the size of the grain in powder (leaves and trunks) and FT-IR characterization was used to demonstrate the presence of various functional groups, such as -C-H (CH3)2, -CO and -OH on the adsorbent. The SEM shows the changes in the surface morphology between leaves and trunks.
Based on the cationic functionality of the samples, due to the presence of hydroxyl groups in its structure, the samples were expected to be effective in removing dyes having anionic functionality like acid red 8 from its aqueous solutions.
The adsorbent was evaluated using batch adsorption process by performing series of batch investigations to identify the maximum sorption isotherms of AR8 onto the adsorbent. Complete adsorption study was carried out and all factors affecting the adsorption process, like the initial pH of acid red 8 in aqueous solution, the contact time of the samples, effect of initial concentration of acid red 8 and the samples dose were also studied.
The results obtained from the adsorption study showed a continuous increment in the amount of the adsorbed dye by decreasing the initial pH of the adsorbate solution which plays an important role in the adsorption efficiency, through affecting the ionization degree of the adsorbate and the surface charge of the adsorbent particles.
The maximum dye removal percentages (89) and (90%) were attained at pH=l using leaves and trunks powders respectively and the percentage of dye removal showed a decrease in its value by increasing the adsorbate initial pH until it reached 15% at pH=10
This occured using 500 mg adsorbent, 50 ml of dye solution (25 ppm) and 200 rpm agitation speed.
Regarding the effect of contact time, it was found that the percentages of dye removal were improved from 48 up to 52 % at 60 min in the leaves powder and from 48 to 53% at 40 min using the trunks powder.
The obtained results of the dye removal percentages using different adsorbent doses from leaves powder showed that, the dye removal percentages was about 69 % when using 100 mg dose. This percentage was found to be increased with increasing the dose until it reached 88 % using 500 mg dose. For trunks powder, the dye removal percentages when using (100 mg) of dose was about 72 %. This percentage was found to be increased by increasing the dose until it reaches 90 % when using (500 mg) dose.
The percentage of AR8 dye removal has been dropped from 70 to 19 % with the leaves powder and also, dropped from 71 to 19 % with the trunks powder with increase in initial AR8 dye concentration from 25 to 500 ppm. However, the quantity of AR8 dye sorbed.