Co-liquefaction of whole Jatropha curcas seed and glycerol using deep eutectic solvents as catalysts

Abstract

Bioenergy is the only renewable carbon energy source and can contribute to future sustainable energy. This paper presents: I) the whole Jatropha curcas seed liquefaction to produce bio-crude oil, using (Na2CO3) as conventional catalyst; and II) co-liquefaction of glycerol and whole Jatropha curcas seed to produce bio-crude oil, using deep eutectic solvents (choline chloride-p-toluene sulphonic acid) as novel catalyst. The effects of process parameters, including reaction temperature, catalyst concentration, and biomass loading were observed. Temperature was the predominant factor. High yield of bio-crude oil (32.87 wt%) was obtained for the liquefaction (I) as compared to yield of bio-crude oil (8.99 wt%) for the co-liquefaction (II). The optimum glycerol addition was 30 wt%. The bio-crude oil I had moisture (6.47 ± 0.27 wt%) and bio-crude oil II was (6.04 ± 0.42 wt%). The oxygen content in bio-crude oil I was (28.15 ± 0.88 wt%) while bio-crude oil II had reduced (21.58 ± 0.70 wt%) oxygen content. The HHV of the bio-crude oil II (31.73 ± 0.69 MJ/kg) is higher than that of bio-crude oil I (28.80 ± 1.32 MJ/kg). Acidic deep eutectic solvents deterred co-liquefaction yield. In conclusion, co-liquefaction decreased the product yield but improved its quality.