, 44:209 | Cite as

Recovery of basic valuable metals and alloys from E-waste using microwave heating followed by leaching and cementation process

  • Rajendra Prasad MahapatraEmail author
  • Satya Sai Srikant
  • Raghupatruni Bhima Rao
  • Bijayananda Mohanty


The whole world understands about the crisis of harmful electronic waste as it is increasing the usage and its disposal. The Government of India asked researchers to come out with innovative alternative solutions, apart from existing conventional methods for safe reuse, recycling and proper disposal particularly for electronic solid waste system. The solution is found which consists of microwave heat treatment followed by acid leaching. The e-waste was first crushed and then the sample was melted in microwave heat treatment to recover the valuable metal in the form of metallic mixture. This mixture was further subjected to acid leaching process in the presence of hydrogen peroxide to form leached liquor. The analysis with X-ray diffraction, image mapping and energy-dispersive X-ray spectroscopy shows that the leached liquor sample mainly contain iron, aluminum and copper, mostly in the form of alloys. The results with field-emission scanning electron microscope analysis, also shows that approximately ninety percent leaching efficiency is observed for nickel, cobalt and copper with hydrochloric acid as solvent, whereas iron and aluminum produced less than forty percent. Further, these results are also compared with the existing methods based on the response surface method through thermal plasma process.


E-waste printed circuit board microwave heating leaching cementation 



The authors are grateful to the Director and Scientists/Researchers of CSIR-Institute of Minerals and Materials Technology, Bhubaneswar for extending the facilities to carry out the work and guiding us with their Mineral and Material processing experience. This research work did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.


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Copyright information

© Indian Academy of Sciences 2019

Authors and Affiliations

  • Rajendra Prasad Mahapatra
    • 1
    • 2
    Email author
  • Satya Sai Srikant
    • 2
  • Raghupatruni Bhima Rao
    • 3
  • Bijayananda Mohanty
    • 1
  1. 1.National Institute of Technology MizoramAizawlIndia
  2. 2.SRM Institute of Science and TechnologyModinagarIndia
  3. 3.CSIR-Institute of Minerals and Materials TechnologyBhubaneswarIndia

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