Loading...

Converting the Organic Constituents of the Li-ion Batteries to Added-value Species with the Possibility of Removing the Environmental Pollutants

Moosavi Shahabi, Mohamad Ali | 2022

196 Viewed
  1. Type of Document: M.Sc. Thesis
  2. Language: Farsi
  3. Document No: 55254 (06)
  4. University: Sharif University of Technology
  5. Department: Chemical and Petroleum Engineering
  6. Advisor(s): Fotovat, Farzam
  7. Abstract:
  8. During the last few years, the number of electric devices using lithium-ion batteries as a source of energy has increased drastically. The lifespan of these batteries is very short (2-3 years) and according to the statistics only 25% of which is recycled. However, considering the variety of materials used in these batteries, recycling them can be highly gainful. One of the technical challenges in the way of recycling Li-ion batteries is the presence of polyvinylidene fluoride (PVDF), that besides raising issues during recycling processes causes the production of toxic fluorine or hydrogen fluoride effluents. The second issue is the presence of metals with high oxidation states in these batteries, which requires strong reductants to increase their extraction rate. In this thesis, with the help of the pyrolysis process, these two problems have been tried to be solved. Considering the capabilities of the pyrolysis technique, it has aimed to develop a technique to recycle the organic fraction of Li-ion batteries, instead of removing them by methods such as incineration. The results of pyrolysis in a fixed bed reactor without any additives (sorbent) showed 46.90% of the bio-oil recovery at T = 551℃, a heating rate of 10.19 ℃/min, and residence time of 15.27 minutes. According to the literature, the pyrolysis of lithium-ion batteries at this temperature results in the release of hydrogen fluoride (HF), which is harmful to health and the environment. Thus, it was attempted to remove HF with the help of calcium oxide with the proven capability for dehalogenation. Conducting pyrolysis in a fluidized bed reactor at T = 441℃ and a cathode-to-calcium oxide mass ratio of 2.32 resulted in 59.32% in the bio-oil recovery.Finally, to compare the performance of pyrolysis in fixed bed and fluidized bed reactors, two tests were carried out at the optimal conditions found for the fluidized bed reactor. Under these circumstances, the bio-oil recoveries were 52.44% and 61.37% for fixed and fluidized beds, respectively. The solid remnants were analyzed by X-ray diffraction analysis, infrared Fourier transform spectroscopy, and scanning electron microscope, while the liquid products of the pyrolysis tests were analyzed by gas chromatography-mass spectrometry and spectrophotometry
  9. Keywords:
  10. Fluidized Bed ; Pyrolysis ; Lithium Ion Batteries ; Fixed-Bed ; Organic Materials Green Recycling ; Electrical Waste

 Digital Object List

 Bookmark

No TOC