Mohammad Javad Jowkar - Master student Chemical engineering Tarbiat modares university Tehran, Iran
Seyed Mohammad Mousavi - Associate professor Chemical engineering Tarbiat modares university Tehran, Iran

Today, pollution of solid waste is one of the most important issues in the field of environmental management. The solid waste because of the widespread use of electronic tools in the past decade and their material content, the most important waste in the twenty-first century has been them. Among the electronic equipment, smart phones, TVs, LCD, laptops, tablets, and digital cameras have the highest demand. All of which has a liquid crystal display (LCD) and light emitting diode (LED) is used. Both LED displays and LED lamps have a variety of metals indium and gallium are mainly. The precise definition of rare metals are not existence. But in general these metals are saying that mineral reserves or production in a particular country, as well as providing a very high demand with their limitations. For extraction of indium from discarded LCDs was used from A.ferroxidans and maximum pulp was 8 g/l and recovery for that is 100% and pH was reached to1.3 and Eh increased dramatically to 533(mv) and cell at the end was equaled to 5*107(cell/ml).

discarded LCDs, Indium, A.ferroxidans, recovery, biological method