Utilization of Molasses as an Agricultural Waste to Synthesize 5-(Hydroxymethyl)furfural Methyl Ester for Enhancing the Cetane Number in Diesel: A Novel Approach for Sustainable Transportation

Effective conversion of molasses into 5-(hydroxymethyl)-furfural (HMF) to develop it as an additive in diesel was performed using an amberlyst-15-supported Cr³⁺ catalyst (<b>CrAm15</b>) in a reduced pressure vessel at 115 °C for 30 min, receiving a yield of 43.37%. The as-prepared <b>CrAm15</b> catalyst was characterized by scanning electron microscopy and energy-dispersive X-ray spectroscopy (SEM/EDS), showing a Cr content of 6.64 wt % on the surface of amberlyst-15. For further investigation, the 5-(hydroxymethyl)-furfural derivative, HMF-Palmitic-OCH₃ (<b>3</b>), was synthesized by a three-step sequential esterification of HMF and fatty acid, reduction of aldehyde to alcohol, and methylation of the hydroxyl group to the ether form. The structure was confirmed by spectroscopic techniques (NMR, mass, and FT-IR). The clear solution of additive <b>3</b> in diesel at 1% w/v improved the cetane number to 55, which is higher than that of commercial diesel.