الفهرس 
Acknowledgement
Effect of temperature on the biosorption of Cu(II) by SCBOnly 14 pages are availabe for public view
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Abstract
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Summary
Heavy metal such as Cr(VI), Cu (II) and organic compounds such as MY 12, DR 81 dyes cause pollution to the environment. This pollution possess a great potential threat to the environment and has its own damaging effects to plants, animals and ultimately to human health, because of its release into the environment and water bodies results in a variety of illnesses related with risk of dermal damage, respiratory problems and several kinds of cancer. A number of researches have been carried out for the removal of heavy metals and dyes from aqueous solutions by using biomass to reduce the problem of limited and scarce water resources which is considered the most important obstacles at all that prevent the continued implementation of plans States, s expansion, maximize benefit from the available water resources and reduce the growing gap between available water resources and the required water needs to maintain international water security and the health of the human.
Thus, our work is to investigate the ability of natural biosorbents for the removing of heavy metals and dyes by studying the effect of modified sugarcane bagasse on adsorption of Cr(VI), Cu (II) and organic compounds such as MY 12, DR 81 dyes from aqueous solution. The model system used in this study consisted of biosorbent, Cr(VI), Cu (II) and organic compounds such as MY 12, DR 81 dyes were taken as pollutant contaminant model because of its harmful effects on human health. This thesis includes three chapters:
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Chapter 1: (Introduction)
The first chapter includes the introduction which shows the background about heavy metals and dyes pollution, their great potential threat to water bodies and human health, different agricultural materials which used for the adsorption of heavy metal and dyes from aqueous solution. Also, it contains Sugarcane bagasse and modified Sugarcane bagasse as biosorbents and adsorption isotherms. Furthermore, it shows the literature survey on Cr(VI), Cu (II) and organic compounds such as MY 12, DR 81 dyes biosorption by plants and adsorption of heavy metal ions and dyes by chemically modified biosorbents.
Chapter 2: (Experimental and Methods)
This chapter provides information about the materials and experimental methods for preparation of biosorbents, working procedure and equipments for measurements which described the prepared biosorbents and determined the concentration of metal ions or dyes solution. It also provides a systemic study of the effects of (pH, temperature, biosorbent dosage, contact time and initial metal ion concentration) on adsorption of Cr(VI), Cu (II) ions and organic compounds such as MY 12, DR 81 dyes from solution by biosorbents (SCB).
Chapter 3: (Results and Discussion)
This chapter includes the results and discussion for removal of heavy metals and organic compounds by modified sugarcane bagasse with 2% or 4 % tartaric acid or citric acid. A systemic study of the effects of (pH, temperature, biosorbent dosage, contact time and initial metal ion concentration) on adsorption of Cr(VI), Cu (II) ions and organic compounds such as MY 12, DR 81 dyes from solution by biosorbents (SCB).
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1- Results and discussion of removal of some heavy metals by modified sugarcane bagasse with 2% or 4 % tartaric acid or citric acid
The amount of Cr(VI), Cu (II) ions and organic compounds such as MY 12, DR 81 dyes adsorbed onto modified sugarcane bagasse increases with increasing in initial concentration of metal ions or dyes. The highest biosorption was observed for Cr(VI), Cu (II) ions and organic compounds such as MY 12, DR 81 dyes at low pH.
The results obtained, removal efficiency and qe of Cr(VI) ions biosorption by SCB Cr(VI) modified with 2 % or 4 % tartaric or citric acid were determined. The amount of Cr(VI) removed by SCB modified by 2 % tartaric acid was 9.04 mg g-1 and removal efficiency 91.23 %, (11.58 mg g-1 and 97.58 % in the case of SCB modified by 4 % tartaric acid) and the amount of Cr(VI) removed by SCB modified with 2 % citric acid at pH 1.2 was 6.49 mg g-1 whereas the removal efficiency was 81.48 %. But in the case of SCB modified with 4 % citric acid the amount of Cr(VI) removed at pH 1.2 was 8.9 mg g-1 and the removal efficiency was 94.19 %.
The amount of Cu(II) removed by SCB modified with 4 % tartaric acid at pH 1.0 was 3.14 mg g-1 and the removal efficiency was 96.9 %. In the case of SCB modified with 4 % citric acid was (2.5 mg g-1 and 91.08 %, respectively). This means that there is strong interaction between the dye and the biosorbent in the acidic solution.
2- Results and discussion of removal of dyes by modified sugarcane bagasse with 2% or 4 % tartaric acid or citric acid
The amount of MY 12 removed by SCB modified with 4 % citric acid at pH 2.8 was 4.085 mg g-1 and the removal efficiency was 81.699 %. In the case of
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SCB modified with 4 % tartaric acid was (4.61 mg g-1 and 92.193 %, respectively). The amount of DR 81 removed by SCB modified with 4 % citric acid at pH 1.0 was 5.41 mg g-1 and the removal efficiency was 90.16 %. In the case of SCB modified with 4 % tartaric acid was (5.64 mg g-1 and 93.95 %, respectively).
The value of Freundlich exponent n indicates better biosorption mechanism and formation of relatively stronger bond between adsorbate and biosorbent as n values were greater than 1.0 and 1/n values were between 0.0 and 1 which means that the biosorption onto modified SCB are favourable under the studied conditions.
Freundlich model has a better fitting model according to linearity coefficient R².
biosorption onto modified SCB with tartaric or citric acid the Freundlich model has a better fitting model according to linearity coefficient R² than Langmuir model.
The adsorption kinetic of the removed metal ions from aqueous solution was studied using the experimental data obtained from sorption time investigation. Both models are tested for suitability using their correlation coefficient, R2.
It was found, the pseudo- second order model is the best fitting model according to linearity coefficients R2 and the experimental qe was closed to the calculated qe for the biosorption by modified SCB with tartaric or citric acid.
from the results obtained, modification of SCB with tartaric acid is better than that of citric acid.