Solvent Extraction and Characterisation of Oil from Neem Seed

ABSTRACT
Neem (Azadirachtaindica) seed oil is widely known for its medicinal, cosmetic, and
industrial applications. This study investigates the extraction and characterization of
neem seed oil using different solvents (n-hexane, ethanol, methanol, and water) to
compare their yields and physicochemical properties. The extraction process was
carried out using the Soxhlet method for the solvent-based extractions , The extracted
oils were analyzed for percentage yield, density, acid value, saponification value, and
peroxide value.The results showed that n-hexane provided the highest oil yield (35%)
followed by methanol (32.7%), ethanol (31.4%), and water (26.8%). The density of the
extracted oils ranged from 0.67 g/cm³ (water-extracted) to 0.875 g/cm³ (n-hexane￾extracted). Acid value analysis revealed that methanol-extracted oil had the highest
acidity (43.5 mg KOH/g), while n-hexane-extracted oil had the lowest (1.5067 mg
KOH/g), indicating better oil stability. Saponification values ranged from 157.08 mg
KOH/g (water-extracted) to 209.25 mg KOH/g (n-hexane-extracted), which correlates
with the oil's potential for soap production. Peroxide values showed significant
variations, with n-hexane-extracted oil having the highest value (7.94 meq/g) and
ethanol-extracted oil the lowest (1.7 meq/g), affecting oil rancidity potential.
Comparing the results with standard values for edible and industrial oils, n-hexane￾extracted oil exhibited the most desirable properties for commercial applications. The
findings suggest that solvent selection significantly affects oil yield and quality. This
study provides insights into the optimal extraction method for neem seed oil and its
potential applications in pharmaceuticals, cosmetics, and biofuel production.