초록
<P><B>Abstract</B></P> <P>In this study, a novel pretreatment for spent coffee waste (SCW) has been proposed which combines two techniques <I>viz.</I> atmospheric air plasma and FeCl<SUB>3</SUB> to create a superior pretreatment that involves Fenton chemistry. The pretreatment was optimised employing Taguchi Design of Experiments, and five parameters were taken into consideration <I>viz.</I> biomass loading, FeCl<SUB>3</SUB> concentration, H<SUB>2</SUB>SO<SUB>4</SUB> concentration, plasma discharge voltage and treatment time. The composition analysis of the pretreated SCW revealed substantial amounts of lignin removal, with a maximum for process conditions of 70kV for 2min in an acidic environment containing 1% H<SUB>2</SUB>SO<SUB>4</SUB>. FTIR, XRD and DSC were performed to characterise the samples. The pretreated SCW after enzymatic hydrolysis yielded 0.496g of reducing sugar/g of SCW. The hydrolysate was subjected to fermentation by <I>S. cerevisiae</I> and led to the production of 18.642g/l of ethanol with a fermentation efficiency of 74%, which was a two fold increase in yield compared to the control.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A novel FeCl<SUB>3</SUB> assisted plasma pretreatment strategy was proposed for lignocellulose. </LI> <LI> Extensive delignification in spent coffee waste was achieved upon pretreatment. </LI> <LI> The polysaccharide fraction of spent coffee grounds was left unaffected. </LI> <LI> High reducing sugar yield was obtained upon hydrolysis of pretreated spent coffee waste. </LI> <LI> Pretreated SCW was found to be a suitable substrate for bioethanol production. </LI> </UL> </P>