Catalytic co-pyrolysis of waste tea residue and waste plastics to carbon nanomaterials: Catalyst support, reaction temperature and product application

Abstract

The search for cost-effective, high-performance catalysts is crucial in catalytic co-pyrolysis. Different Fe-Mo@X catalysts (X = Al2O3, MgO) and reaction temperatures (600 ℃, 700 ℃, 800 ℃, 900 ℃) were tested to optimize hydrogen production and carbon quality while also exploring CNTs degradation performance. The results indicate that both catalyst type and operating parameters are highly dependent on the growth of carbon nanotubes and hydrogen. The FeMo@Al2O3 catalyst exhibits superior catalytic activity attributed to its more abundant mesoporous structure and higher specific surface area. Specifically, FeMo@Al2O3 achieved the highest yield of carbon nanotubes (84.42%) at 700 ℃, and attained the maximum hydrogen yield (49.57%) at 900 ℃. However, the CNTs synthesized from FeMo@MgO exhibited fewer defects, higher graphitization degree and purity (Raman and TPO). CNTs/MgO significantly enhanced the degradation efficiency of Clothianidin by virtue of their superior electron transport properties and chemical bonding between MgO and CNTs.