Title Page
Abstract
Contents
CHAPTER 1. Introduction 10
CHAPTER 2. Experimental 13
2.1. Chemicals and Materials 13
2.2. Electrocoagulation of polyethylene 13
2.3. Magnetic separation and removal efficiency calculation 14
2.4. Photodegradation of polyethylene 14
2.5. Post-treatment of floc for battery application 15
2.6. Material characterization 15
2.7. Electrochemical measurements 16
CHAPTER 3. Results and Discussion 17
3.1. Mechanism of electrocoagulation 17
3.2. Effect of plastic size and NaCl concentration on EC reaction 24
3.3. Floc separation using magnetic property 26
3.4. Inhibition effect of Fe₃O₄ on photodegradation 28
3.5. Replacement of graphite by heat-treated floc for lithium-ion battery anode 31
CHAPTER 4. Conclusion 33
References 34
Table 1. Measured weight data after electrocoagulation with/without PE and calculated removal efficiency. 27
Table 2. Carbonyl index calculated by FT-IR data before/after 300 h photodegradation. 30
Figure 1. Voltage profile during electrocoagulation with 0.4 wt% and 3.5 wt% NaCl electrolyte. 18
Figure 2. SEM images of polyethylene (a) before and (b) after electrocoagulation. (c) FT-IR spectrum of pristine PE and EC floc. (d) XRD patterns of EC floc at... 19
Figure 3. XPS spectra of (a) electrode and (b) floc at different reaction time. 21
Figure 4. pH profile of electrolyte at different reaction time 23
Figure 5. SEM images of (a) 200 μm-0.4 wt% floc and (b) 40 μm-3.5 wt% floc. 25
Figure 6. Photographs of magnetic separation. (left) before and (right) after separation. 27
Figure 7. SEM images of samples before and after photodegradation. (a) pure PE, (b) acid PE, (c) acid floc and (d) floc. (e) weight changes from 0 h to 300 h. (f)... 30
Figure 8. SEM images of heat-treated floc. (a) G/flocAir, (b) G/flocAr.[이미지참조] 32
Figure 9. EIS data at (a) 0 cycle, (b) after 100 cycle. (c) rate capability of graphite, G/flocAir, G/flocAr. (d) charge/discharge capacity profile of graphite,...[이미지참조] 32