[BMIM]OTf and alcohol-based DES combination with a selected organic solvent (acetone and acetonitrile) have
been proven to efficiently extracting rotenone (isoflavonoid biopesticide) compound compared to individual organic
solvents. Their efficiency builds up interest to study the solvent-solute interaction that occurs between both selected
solvent systems with rotenone. The interaction study was analyzed using FTIR, 1D-NMR and 2D- NMR (NOESY, HMBC).
Correlation portrayed by NOESY and HMBC of [BMIM]OTf - standard rotenone mixture predicted probable hydrogen
bonding between the oxygen of rotenone with acidic proton C2-H of [BMIM]OTf. While for the alcohol-based DESrotenone
mixture, the correlation shows probable interaction to occur between methyl and methoxy group rotenone
with the hydroxyl group of 1,4-butanediol. In conclusion, potential hydrogen bonding that occurs between solvent
and solute aid towards the solvent efficiency in extracting rotenone compound while emphasizing on the low cost and
green mediated solvent systems.
Glycerol, the main by-product in biodiesel manufacturing, is a useful and environment-friendly solvent for many organic
and inorganic substrates. This study investigates the effects of soaking using glycerol, silicone oil, dimethyl sulfoxide
(DMSO) and Organosolv (1:1 water: ethanol) on energy consumption in the process of grinding kempas wood and on
the particle size of ground kempas. Kempas wood chips were soaked in various solvents at 90°C for 1 h. The structural
characterisation of untreated and treated kempas was analysed using CHNS, ATR-FTIR and XRD. Meanwhile, the grinding
energy was calculated based on power per unit time while particle size was analysed using nested column sieves. Glycerol
has high stability, good compatibility with other chemicals and is environmentally friendly. Glycerol-soaked kempas
consumed less energy which led to energy saving of up to 0.015 W h and exhibited the smallest average particle size
(263 µm) close to that of untreated kempas due to glycerol lubricating properties. Therefore, glycerol can be used as
an alternative to conventional solvents in reducing the grinding energy consumption and particle size of lignocellulosic
biomass.