الفهرس 
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Abstract
- Packed-bed electrode cell was successfully applied to the treatment of waste water containing copper ions. Removal efficiency of 96% could be attained when operating parameters were fixed at:
- Current density: 500 A/m2.
- Electrolysis time: 30 minutes.
- Concentration of the supporting electrolyte, NaCl, was 0.5 M.
- Initial pH of the electrolyte was 3
- Initial copper ion concentration was 100 mg/l (Using CuSO4 salt).
2- For initial copper ion concentration > 100 mg/l, to achieve high removal%, longer time of electrolysis was needed.
3- Current efficiency decreases as time of electrolysis is increased due to the commencement of side reactions as a result of decreased copper ion concentration at constant applied current density.
4- Type and concentration of supporting electrolyte have a remarkable effect on the removal percent and current efficiency. Using of NaCl lead to better results than the utilization of Na2SO4.
5- It was confirmed that the solution flow rate has an important effect on both removal percent and current efficiency of copper. At low solution flow rate higher removal percent and current efficiency values were obtained.
6-The results indicated that the performance of fixed bed is better than that of fluidized bed from the points of view of removal percent and current efficiency.
In this study two different shapes of current collectors were used to investigate its influence on the current efficiency and removal percent of copper. The two collectors had the same surface area but were different in the geometric shape. Collector (2) gave removal percent and current efficiency of 75% and 99.4%, respectively, while collector (1) gave removal percent of 55 % and current efficiency of 67%. This is attributed to more uniform potential distribution over the cathode surface in case of collector (2) than in case of collector (1). This result was confirmed by studying (i-E) relation of copper deposition, for both collectors at different points on the surfaces of electrodes.
7-The electrodeposition of copper was found to follow first-order kinetics and dependant on initial copper concentration, applied current density and supporting electrolyte concentration then it described by the equation
C = Co e-kt
where
k = ko e- (-C.D)
The value of ko (is the value of k when C.D = 0)seemed to be independent of the initial concentration of copper in the waste solution. The value of (is the slope of the line representing the relation between ln k versus applied current density), however, depends on the initial concentration of copper. By introducing this simple model, good agreement could be obtained between predicted and observed data.
8-Finally, from cost analysis study of this work, we can conclude that, the plant of the present work is capable of processing 0.8 l/min. or 9000 l/year of feed containing 350 mg/l of copper. A total of 3.1 kg/year of copper will be recovered.