Ethylene vinyl acetate co-polymer degradation by environmental microbes
Delamination of EVA encapsulant is one of the more difficult and crucial steps in the recycling of photovoltaic modules. Currently, several methods that are hazardous and highly energy-intensive such as disintegration and chemical dissolution are being adopted by industries to delaminate EVA enca...
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| Other Authors: | |
| Format: | Final Year Project (FYP) |
| Language: | English |
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Nanyang Technological University
2022
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| Online Access: | https://hdl.handle.net/10356/157376 |
| _version_ | 1824455779058450432 |
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| author | Wong, Bryan Jun Long |
| author2 | Nripan Mathews |
| author_facet | Nripan Mathews Wong, Bryan Jun Long |
| author_sort | Wong, Bryan Jun Long |
| collection | NTU |
| description | Delamination of EVA encapsulant is one of the more difficult and crucial steps in the
recycling of photovoltaic modules. Currently, several methods that are hazardous and
highly energy-intensive such as disintegration and chemical dissolution are being
adopted by industries to delaminate EVA encapsulants. This study explores the
possibility of using environmental microbes as a sustainable alternative to
conventional methods in delaminating the EVA encapsulant. Commercial
crosslinked EVA polymeric sheets were used in this study to be biodegraded in
liquid media using Rhodococcus ruber, (R.ruber) standard strain as well as
environmental microbial samples obtained from NTU, Semakau landfill, and
MacRitchie reservoir. The biodegradation effects of the microorganisms on the EVA
samples were evaluated using different techniques such as attenuated total
reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), measurement of
optical density (OD), scanning electron microscopy (SEM), and atomic force
microscopy (AFM).
Carbonyl index (CI) calculation obtain from FTIR spectra revealed a reduction in CI
levels in the EVA sheets after 40days of degradation. ATR-FTIR measurements also
captured biofilm formations by R.ruber when biodegrading the EVA sheets. Overall
results obtained showed that environmental microbial samples fair better at
degrading the EVA polymer than standard R.ruber microbes. Among them,
microbial samples from NTU showed the highest potential when compared to other
environmental strains. When tested for the presence of laccase and esterase enzymes
using Remazol brilliant blue R (RBBR) dye and Tween 20 as substrates in agar-based
experiments, environmental strains from NTU were tested positive for both
esterase and laccase production while R.ruber did not exhibit any production of the
said enzymes. |
| first_indexed | 2025-02-19T03:43:37Z |
| format | Final Year Project (FYP) |
| id | ntu-10356/157376 |
| institution | Nanyang Technological University |
| language | English |
| last_indexed | 2025-02-19T03:43:37Z |
| publishDate | 2022 |
| publisher | Nanyang Technological University |
| record_format | dspace |
| spelling | ntu-10356/1573762022-05-18T00:18:27Z Ethylene vinyl acetate co-polymer degradation by environmental microbes Wong, Bryan Jun Long Nripan Mathews School of Materials Science and Engineering Suresh Akshaykumar Nripan@ntu.edu.sg Science::Biological sciences::Microbiology::Microorganisms Engineering::Materials Delamination of EVA encapsulant is one of the more difficult and crucial steps in the recycling of photovoltaic modules. Currently, several methods that are hazardous and highly energy-intensive such as disintegration and chemical dissolution are being adopted by industries to delaminate EVA encapsulants. This study explores the possibility of using environmental microbes as a sustainable alternative to conventional methods in delaminating the EVA encapsulant. Commercial crosslinked EVA polymeric sheets were used in this study to be biodegraded in liquid media using Rhodococcus ruber, (R.ruber) standard strain as well as environmental microbial samples obtained from NTU, Semakau landfill, and MacRitchie reservoir. The biodegradation effects of the microorganisms on the EVA samples were evaluated using different techniques such as attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), measurement of optical density (OD), scanning electron microscopy (SEM), and atomic force microscopy (AFM). Carbonyl index (CI) calculation obtain from FTIR spectra revealed a reduction in CI levels in the EVA sheets after 40days of degradation. ATR-FTIR measurements also captured biofilm formations by R.ruber when biodegrading the EVA sheets. Overall results obtained showed that environmental microbial samples fair better at degrading the EVA polymer than standard R.ruber microbes. Among them, microbial samples from NTU showed the highest potential when compared to other environmental strains. When tested for the presence of laccase and esterase enzymes using Remazol brilliant blue R (RBBR) dye and Tween 20 as substrates in agar-based experiments, environmental strains from NTU were tested positive for both esterase and laccase production while R.ruber did not exhibit any production of the said enzymes. Bachelor of Engineering (Materials Engineering) 2022-05-14T10:50:24Z 2022-05-14T10:50:24Z 2022 Final Year Project (FYP) Wong, B. J. L. (2022). Ethylene vinyl acetate co-polymer degradation by environmental microbes. Final Year Project (FYP), Nanyang Technological University, Singapore. https://hdl.handle.net/10356/157376 https://hdl.handle.net/10356/157376 en application/pdf Nanyang Technological University |
| spellingShingle | Science::Biological sciences::Microbiology::Microorganisms Engineering::Materials Wong, Bryan Jun Long Ethylene vinyl acetate co-polymer degradation by environmental microbes |
| title | Ethylene vinyl acetate co-polymer degradation by environmental microbes |
| title_full | Ethylene vinyl acetate co-polymer degradation by environmental microbes |
| title_fullStr | Ethylene vinyl acetate co-polymer degradation by environmental microbes |
| title_full_unstemmed | Ethylene vinyl acetate co-polymer degradation by environmental microbes |
| title_short | Ethylene vinyl acetate co-polymer degradation by environmental microbes |
| title_sort | ethylene vinyl acetate co polymer degradation by environmental microbes |
| topic | Science::Biological sciences::Microbiology::Microorganisms Engineering::Materials |
| url | https://hdl.handle.net/10356/157376 |
| work_keys_str_mv | AT wongbryanjunlong ethylenevinylacetatecopolymerdegradationbyenvironmentalmicrobes |