Waste fishing gear is a major source of water pollution that causes serious environmental problems. As an example, nets and ropes are produced using different polymers, which are exposed to mechanical stress, oxygen, salt water, ultraviolet radiation, etc. Moreover, their polymeric chains decompose and are eroded releasing various chemical species. Due to these reasons they must be properly disposed of. In this work, there was analysed the decomposition process of substances and characterised the produced chemical compounds. Thermal analysis has demonstrated that the largest part of material is decomposed to volatile monomers within the range of 400–440 °C at different heating rates of 5, 15, 20 and 30 °C/min. Based on ATR-FTIR results, the main polymer of fishing nets was found to be Nylon 6. In addition, spectroscopic FTIR 3D analysis of gases confirmed that decomposition of Nylon 6 corresponds to the spectrum of caprolactam during the most intense decomposition. Evolved gas analysis of waste fishing nets showed that pyrolysis of Nylon 6 results in the reduction of the material into monomers, and indicates significant potential for the use of the material and process in the production of caprolactam. This study proposes an innovative waste recycling technique enabling to reduce the volume of waste dumped into landfills.
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