Marine macroalgae offers a promising third generation feedstock for the production of fuels and chemicals, avoiding competition with conventional agriculture and potentially helping to improve eutrophication in seas and oceans. However, an increasing amount of plastic is distributed into the oceans, and as such contaminating macroalgal beds. One of the major plastic contaminants is nylon 6 derived from discarded fishing gear, though an increasing amount of alternative nylon polymers, derived from fabrics, are also observed. This study aimed to assess the effect of these nylon contaminants on the hydrothermal liquefaction of Fucus serratus. The hydrothermal liquefaction (HTL) of macroalgae was undertaken at 350 °C for 10 min, with a range of nylon polymers (nylon 6, nylon 6/6, nylon 12 and nylon 6/12), in the blend of 5, 20 and 50 wt.% nylon to biomass; 17 wt.% biocrude was achieved from a 50% blend of nylon 6 with F. serratus. In addition, nylon 6 completely broke down in the system producing the monomer caprolactam. The suitability of converting fishing gear was further demonstrated by conversion of actual fishing line (nylon 6) with the macroalgae, producing an array of products. The alternative nylon polymer blends were less reactive, with only 54% of the nylon 6/6 breaking down under the HTL conditions, forming cyclopentanone which distributed into the biocrude phase. Nylon 6/12 and nylon 12 were even less reactive, and only traces of the monomer cyclododecanone were observed in the biocrude phase. This study demonstrates that while nylon 6 derived from fishing gear can be effectively integrated into a macroalgal biorefinery, alternative nylon polymers from other sectors are too stable to be converted under these conditions and present a real challenge to a macroalgal biorefinery.

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评估大型藻类水热液化过程中各种尼龙聚合物的转化率

海洋大藻类为生产燃料和化学物质提供了有希望的第三代原料，避免了与常规农业的竞争，并有可能帮助改善海洋的富营养化。然而，越来越多的塑料被分配到海洋中，并因此污染了大藻类床。主要的塑料污染物之一是源自废弃渔具的尼龙6，尽管也观察到了越来越多的源自织物的替代尼龙聚合物。这项研究旨在评估这些尼龙污染物对锯缘海藻的水热液化的影响。。大型藻类的水热液化（HTL）在350°C下进行10分钟，其中加入了一系列尼龙聚合物（尼龙6，尼龙6/6，尼龙12和尼龙6/12），共混物5、20和相对于生物质为50重量％的尼龙；从50％的尼龙6和锯缘青蟹（F.serratus）的混合物中获得了17wt。％的生物粗品。另外，尼龙6在产生单体己内酰胺的体系中完全分解。通过将实际的钓鱼线（尼龙6）与大型藻类进行转换，进一步证明了转换渔具的适用性，生产出一系列产品。替代的尼龙聚合物共混物的反应性较低，只有54％的尼龙6/6在HTL条件下分解，形成了分布在生物原油相中的环戊酮。尼龙6/12和尼龙12的反应性甚至更低，并且在生物原油相中仅观察到痕量的单体环十二烷酮。这项研究表明，虽然源自渔具的尼龙6可以有效地整合到大型藻类生物提炼厂中，