In this paper, a previously developed Aspen Plus model for gasification of biomass was adapted to the gasification of microplastics in a temperature range of 400-1200 degrees C. The effect of parameters such as equivalence ratio (ER), steam-to-biomass ratio (SBR) and gasification temperature in hydrogen production was evaluated, as well as three different gasifying agents namely air, 02 and steam were tested. The relationship between all these variables was assessed in order to better characterize the final syngas. Results showed that for higher hydrogen yields, microplastics composition should be majorly polyethylene terephthalate (PET), assuring H-2 molar fraction contents in the order of 63-66%. The achieved lower heating value (LHV) was 9.2 MJ/Nm(3) which endorsed high-quality syngas.