الفهرس 
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Abstract
Copper is a widely used metal in different industries and is released into the environment primarily through mining, sewage treatment plants, solid waste disposal, welding, electroplating processes, electrical wiring materials, plumbing supplies (pipes, faucets, braces, and various forms of tubing), agricultural processes, gear wheel, air conditioning tubing and roofing owing to excellent physical and mechanical properties, electrical and thermal conductivity, good corrosion resistance, ease of fabrication and installation.
Ultra-trace amount of copper i.s essential for human, animals, and microorganisms. However, excessive copper can be detrimental. For instance, for human it will cause stomach upset and ulcer, mental retardance, liver and brain damage, and so on.
The potential sources of copper in industrial effluents include metal cleaning and plating baths, pulp, paper board mills, printed circuit board production, wood pulp production and the fertilizer industry, etc. Therefore, removal of copper from effluents is essential to protect the water resources and also to slowdown the fast depletion of copper sources.
Various methods to remediate heavy metal contaminated soils and wastewaters exist, including thermal, biological, physical and chemical treatments. However, chemical methods, such as precipitation, ion-exchange and solvent extraction require high capital and operation costs and may produce large volumes of solid wastes. Hence, there is a crucial need for the development of a method that is highly selective, more efficient, easy to operate and hence cost effective. Adsorption and biosorption could be a good alternative technology. In recent years, there has been an increase in the use of biological materials induding agricultural and industrial solid wastes as adsorbents for the removal of heavy metals. The advantage of using agricultural solid wastes is that it saves disposal costs while alleviating potential environmental problems. Agricultural by-products such as peat, wood, pine park, banana pith, rice bran, wheat bran, peanut hull, wool, sunflower, grape stalks wastes, sugar beet pulp, olive mill solid residue, sawdust, leaves, walnut expeller meals, orange peel have been demonstrated to remove heavy metal ions from wastewater.
The present work aims to study the adsorption characteristics of powdered peanut hull for removing Cu(II) from aqueous solutions in a batch system. The effect of different variables such as pH, contact time, temperature, initial Cu(II) concentration, adsorbent particle size and adsorbent weight has been studied. It was found that the best %removal of Cu(II) ions was happened at the following condition: pH of 4, time of shaking of 1 h, the lowest initial concentration of 150 ppm, weight of peanut hull of 1 g per 50 ml of the solution, peanut hull particle size < 250 ~lm and at room temperature. In addition, infrared spectra (FT-IR), X-ray diffraction (XRD) techniques, thermal stability, surface area and pore size dis~ribution are performed for characterization of peanut hull.
The adsorption equilibrium study showed that Langmuir model gave best fitted of the experimental data.
The experimental data were analyzed using four different adsorption kinetic models:
Lagergren pseudo-first-order model, pseudo-second-order model, intra-particle diffusion model and Elovich model. The kinetic constants were also calculated depending on