Metallised seaweed-derived bio-char catalyst preparation and its application in the pyrolysis process for the waste fishing nets and marine biomass utilisation

Abstract

Marine biomass and plastic wastes are one of the most significant ecological issues of water pools, which could be adapted for energy recovery through pyrolysis. Moreover, a catalytical process could be applied to improve the quality and adaptability of the formed product. This study investigates seaweed (SWD) and fishing nets (FN) standalone pyrolysis with and without commercial ZSM-5 catalysts. Therefore, the newly created seaweed char-based metals (iron and copper) impregnated catalysts were investigated using SEM-EDS, XRD, and pore size distribution examination and applied for the selected feedstock pyrolysis process. The study revealed that bio-char contains 335 m2/g of surface area, while the impregnation process increased it to 1066 and 790 m2/g with copper and iron, respectively. Pyrolysis products investigation showed that the main derivatives of the FN liquid fraction are caprolactam and hexanenitrile, while the SWD liquids mainly consist of variously substituted aromatic and phenolic compounds. Copper-impregnated catalyst increased the amount of caprolactam to 54.3 % and hexanenitrile to 31.7 % (FN), while the amount of toluene was increased to 84.2 % (SWD) in the total liquid fraction. This research provides information regarding the promising route of newly created biochar preparation and application as a catalyst for the pyrolysis product upgrading.