Conversion of Citrus Fruit Peel into a Value-Added Product, Bio-Oil

The present study aimed to investigate the bio-oil from the blended citrus fruit peel by hydrothermal liquefaction process. Huge amounts of fruit peel waste are disposed of in the open environment without any proper management. Such fruit peels are considered a potential bio-resource to be converted into economically valuable products like bio-oil. Since the citrus fruit peel is a rich source of moisture content, a hydrothermal liquefaction process was introduced to produce bio-oil from cellulose, and lignocellulose. The experimental design against temperature, time, and biomass concentration optimization was carried out which was confirmed by the ANOVA f and p test that reveals time and temperature influenced the bio-oil yield drastically. As the time and temperature rise more than 60 min and 280°C, the volatile substance present in the biomass converts itself into solid residue which has a negative impact on bio-oil production, compared with biomass concentration. The maximum yield of bio-oil was recorded as 29.4% at 280°C at 60min reaction time and 80g/200mL concentration as optimized parameters. The GCMS reveals the presence of hydrocarbons and alkanethiol which are flammable and hold the standards of commercial transportation fuel but hold nitrogen and oxygen-containing compounds to pull down the fuel standards. Thus, the produced bio-oil can be blended with the transportation fuel after the upgradation process for efficient results.