Distribution of Phenolic Compounds from Ulva Lactuca and Sargassum sp. via Slow-Pyrolysis

Ulva Lactuca and Sargassum sp. are rapidly expanding algae that can be used as a source of bioenergy. Due to its high moisture and inorganic content, the direct use of Ulva Lactuca and Sargassum sp. for energy purposes is deep. Therefore, thermochemical processing, such as pyrolysis, is required to produce useful products, such as bio-oil. This study seeks to undertake a detailed investigation of bio-oil production from Ulva Lactuca and Sargassum sp. to provide useful information for its continued commercialization. The pyrolysis of Ulva Lactuca and Sargassum sp. was investigated for bio-oil production within the temperature range of 400-600 °C and reaction time of 10-50 min. The highest proportion of bio-oil was retrieved at 500 °C with yields between 18.5 and 30.2 wt%. As the pyrolysis temperature rose to 600 °C, the bio-oil yields slightly increased, but the prolonged reaction time did not significantly increase in bio-oil yields. Gas chromatography-mass spectrometry (GC-MS) was employed to elucidate the chemical composition found in the bio-oil product. The results showed that phenolic compounds increased from 9.64 to 16.73 area% with an increase in temperature. The highest phenolic compounds for Ulva Lactuca and Sargassum sp. were obtained at about 13.25% and 16.73%, respectively. The variations in the distribution of total phenols may be due to variations in species, sediment, and surrounding water quality. The high phenolic achieved at the highest possible yield indicates its potential to be used for the production of renewable phenolic resins.