Informatics Publishing Limited

Rajendra Prasad Mahapatra ¹, Satya Sai Srikant ², Raghupatruni Bhima Rao ³, Bijayananda Mohanty ¹

Affiliations
1 National Institute of Technology, Mizoram - 796 012, IN
2 SRM Institute of Science and Technology, Modinagar - 201 204, IN
3 CSIR-Institute of Minerals and Materials Technology, Bhubaneswar - 751 013, IN

Abstract

The main aim of the present study is to develop a new method to recover gold and other precious metals such as copper, silver, etc. with the judicious combination of microwave heating and acid leaching of e-waste samples like printed circuit board of computers, mobiles, electronic devices, etc. In the present study, microwave heating is much required for segregation of melted plastics and metals from e-waste and it also generates high temperature in much lesser time. The investigation basically consists of seven stages, i.e. heating the e-waste using microwave energy, grinding, physical separation of molten plastics and metal slag followed by leaching in nitric acid, leaching in aqua regia for unreacted materials, removing with concentrated nitric acid and washing and purifying the metal deposits. The results obtained from XRD, FESEM-EDAX and TEM studies confirm that precious metals like gold and silver can be obtained with the new method, which is also an environmental friendly approach.

Keywords

Aqua Leaching, EDAX, E-waste Sample, FESEM, Image Mapping, Microwave Heating, TEM, XRD.

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