Biodiesel synthesis from mixed non-edible oil feedstock using K₂CO₃ in NH₄OH Catalyst mixture

ABSTRACT

In the present study, a new approach has tried to synthesize and optimize biodiesel production from mixed oils (Pongamia and Mahua) using an in-situ generated KOH from K₂CO₃ in an NH4OH catalyst mixture using response surface methodology (RSM). A maximum biodiesel yield of 96.5 v/v% was obtained at a catalyst concentration (CC) of 1.5 g K₂CO₃ in 0.75 g of NH₄OH, oil to methanol molar ratio (M:O) of 7:1 at a reaction temperature (RT) of 55°C in 75 min reaction time (Rt). The obtained biodiesel yield is compared and found to be maximum (96.5 v/v%) for K₂CO₃ in NH₄OH catalyst mixture than K₂CO₃ in H₂O, direct K₂CO₃ and Conventional KOH methods. Furthermore, the presence of carbonate and ammonium ions in the reaction medium resulted in an increased biodiesel yield due to the less possibility for free water molecules formation and with a minimal amount of KOH to drive the reaction toward the right-hand side. The GC-MS, 1HNMR and FTIR techniques were used to confirm the conversion of esters.

KEYWORDS:

• Biodiesel
• Catalyst mixture
• In-situ KOH
• K₂CO₃ in NH₄OH
• Pongamia and Mahua oil

Disclosure statement

No potential conflict of interest was reported by the authors.