Abstract
In the proposed method, crude enzymes extracted from waste dry leaves of 15 different plants showing protease activity were used for removal of silver from exposed medical X-ray film by hydrolysis of gelatin. Optimum operating pH and temperature for crude protease extract was found to be 7 and 50 °C, respectively. The X-ray film before and after protease treatment was analysed using FTIR (Fourier-transform infrared spectroscopy) and EDS (Energy-Dispersive X-Ray Spectroscopy). The slurry obtained after smelting process analysed using EDS shows 99.8% of silver recovery. The result confirms that the enzyme extraction process recovers silver and PET (polyethylene terephthalate) in eco-friendly treatment methodology when compared to conventional chemical treatment process.
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Arun, C., Lakshmi, P.M., Sethupathy, A. et al. Study on removal of silver and polyethylene terephthalate from exposed radiography films using enzyme protease. J Mater Cycles Waste Manag 23, 1947–1954 (2021). https://doi.org/10.1007/s10163-021-01267-8
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DOI: https://doi.org/10.1007/s10163-021-01267-8