Abstract
Oil was extracted from spent coffee grounds using methanol. Methanol is not a popular solvent for oil extraction because of its toxicity but it is ideal for biodiesel production. The SCG was determined to contain 17.1 % wt% oil by extraction using hexane for 16h. The highest oil extraction 8.5 wt% was observed on a dry sample at a separation temperature of 25 ˚C representing only 50% recovery. Oil extraction was observed to depend on separation temperature and SCG water quantity. The extracted oil was characterised by a number of methods. Fourier-transform infrared spectroscopy (FTIR) results showed no difference in functional groups between hexane and methanol extracted oil. The Refractive Index (RI) results also suggested similarity in fatty acid chain length for oils extracted by these solvent. However, it was observed that oil extracted by hexane had higher amounts of FFA compared to methanol extracted oil.