Optimisation of the acid catalysed pretreatment of areca nut husk fibre using the Taguchi design method

Pretreatment is an inevitable high energy consuming process en route to biofuel production which alters the recalcitrant structures of lignocellulosic biomass. An attempt has been made to pretreat the areca nut husk fibre using dilute sulphuric acid. The Taguchi robust design method of optimisation (L9 orthogonal array) was applied to this acid catalyzed pretreatment process. Cellulose crystallinity is directly proportional to the degree of enzymatic hydrolysis of any kind of cellulosic substrate; the present study considers it as an index to optimise the process parameters. The study showed that the sulphuric acid concentration plays the major role during the pretreatment of areca nut husk (57% contribution) followed by the duration of operation (24.98% contribution) and solid loading (14.3% contribution). The optimal factors obtained from the design of experiments were further validated using the experimental results.

► Non-conventional biomass of areca nut husk is considered. ► Pretreatment by acid catalysis followed enzymatic hydrolysis. ► Taguchi robust design method of optimisation was applied. ► Cellulose crystallinity of the biomass was reduced by 49.8%. ► Areca nut biomass is a suitable candidate for biofuel feedstock.