Production of aromatic hydrocarbons by catalytic co-pyrolysis of microalgae and polypropylene using HZSM-5

In the current study, the thermogravimetric behavior of Nannochloropsis sp. (NS), polypropylene (PP) and mixed samples (NS: PP = 1:1) with and without catalyst were investigated by TGA analysis. To promote the efficient production of aromatic hydrocarbons, co-pyrolysis of NS and PP over the HZSM-5 zeolite catalyst were carried out in a bench-scaled fixed bed reactor. The effects of the reaction temperature (500-900 degrees C), NS/PP mass ratio (1: 0, 3: 1, 2: 1, 1: 1, 1: 2,1: 3 and 0: 1) and feedstock/catalyst mass ratio (1:0-1:10) on the relative content of aromatics were investigated. The results showed that the catalytic co-pyrolysis of NS and PP exhibited a synergistic effect on the generation of aromatic hydrocarbons compared to their individual pyrolysis. The relative content of aromatic hydrocarbons compounds and mass yield of monoaromatic hydrocarbons in oil from catalytic co-pyrolysis of NS and PP with HZSM-5 could reach to 77.04 area%, and 0.1223 g/(g.sample), respectively. Based on chemical composition analysis of the oil, the mechanisms for the formation of major aromatic hydrocarbons during the catalytic co-pyrolysis of NS and PP were further discussed.