Obtaining biogas from Mediterranean pine tree (Pinus pinea) seed shell and plastic catalyst seed shell mixture with pyrolysis process

This study reveals the investigation of the hydrogen and methane gas potential resulting from the pyrolysis of Mediterranean pine tree seed coat biomass and polyethylene catalyst. In the study, firstly, the viscosity, density and degassing point of polyethylene materials were determined. Seed shells were supplied and sorted for the pyrolysis process. The seeds were mixed with polyethylene materials selected as catalysts in the proportions we determined. Pyrolysis was carried out at a temperature of 600 °C at a rate of 50 °C/min. The obtained gases were analyzed with a gas chromatography device. In the final stage of the experiments, solid residues were observed under an optical microscope and their microstructures were also examined. The results showed that mediterranean pine core bark biomass and its blend with low-density polyethylene could produce methane and hydrogen gases. The M8 catalyst, which has one of the lowest viscosity values (0.45 g/10 min.) and the highest density values (0.950 g/cm3), provided the highest methane and hydrogen gas yield. In pyrolysis experiments, 38.44% CH4, 19.50% CO2 and 42.06% H2 gases were obtained from the Mediterranean pine tree seed coat biomass. Additionally, CO2 emission values of biomass were calculated and compared with DEFRA values. The study showed that since hydrogen and methane can be obtained through the pyrolysis process, mediterranean pine tree seed husk can be classified as a new biomass source and has potential as an alternative fuel to fossil-based fuels for internal combustion engines.