الفهرس 
CHAPTER ONE INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
The demand for portable sources of energy has arose fiercely in the 20s century due to the burst of small electronic devices, thus supported the generation of e-waste, which contain components that can be hazardous to the environment so retrieving these metals attracted much attention from both economic and environmental points of view.
Batteries and cells are storing devices of electrochemical energy which is released as electricity. Depending on how long the charge lasts the cells are divided into primary and secondary. Button and coin cells were developed to miniaturize battery packs and solve pile up problems. The cells have small weight, high capacity and long operating life used in many portable devices as remote controls, hearing aids, calculators and thermometers, etc. These batteries become waste after their life is over. The inappropriate discarding of exhausted batteries endangers the environment; hence, recycling these batteries is crucial.
This work aims to recover valuable metals from discarded button and coin cells, a new hydrometallurgical route was innovated by dissolving the entire battery unlike other studies that dismantle the case or crush the battery.
Samples were collected from battery stores, sorted to choose only two types of button and coin cells (SR and LR batteries). Different acids like HCl, H2SO4, and HNO3 were experimented to dissolve the battery, nitric acid only displayed hopeful results. Leached solution was measured using ICP-OES spectrometry.
Selective precipitation of metals from SR battery started by extracting silver using sodium chloride, iron and zinc were precipitated using sodium hydroxide at different pH values using hydrogen peroxide as oxidizing agent.
LR battery was first treated with sodium hydroxide to precipitated iron, zinc was selectively precipitated using oxalic acid in highly acidic medium, while manganese was precipitated using sodium hydroxide in alkaline medium.
Optimum conditions for leaching metals were found to be as follows: 7M nitric acid, S/L ratio as 2/50 ml 30 0C soaked for 30 minutes, 150 rpm magnetic stirring for both types of batteries.
In SR battery, silver, iron and zinc were efficiently precipitated 99%, 98.6% and 92% respectively. Also in LR battery, metals were successfully precipitated in which iron, zinc and manganese showed promising results giving 99%, 98.7 and 96.5% respectively.