Chemical and Enzymatic Valorisation of Confectionery Waste into Biofuel: An Application of Circular Economy

Abstract

Waste oil was extracted from lollipop effluent stream using a mixture of organic solvents viz. n-hexane and ethyl acetate. Lollipop effluent samples found to contain ~ 10-18 wt.% oil. Subsequently, the oil was subjected to biodiesel synthesis under solvent free condition using chemical and enzymatic catalysts. Among the base catalysts used, KOH catalyzed reaction gave highest biodiesel yield (99 %) in 20 minutes. Furthermore, nine different lipases were screened as catalysts for biodiesel preparation from lollipop effluent oil. The screening experiments revealed that Novozyme-435 was best among the lipases which gave 94 % biodiesel in 18 h at 40 0C.