▎ 摘　　要

NOVELTY - Facile production of single layer graphene sheets by liquid phase exfoliation of graphite in biomass-derived solvents, involves: (i) submerging graphite in biomass derived solvents comprising levulinic acid; (ii) ultrasonication of the obtained dispersion of graphite in levulinic acid for 60-160 minutes; (iii) keeping the ultrasonicated dispersion for 24 hours at room temperature; (iv) melting the thus formed levulinic acid crystal and centrifuging for 20-120 minutes to form graphene sheets; and (v) centrifuging graphite dispersion obtained in step (ii) to get single layer graphene sheets. USE - The process for the facile production of single layer graphene sheets by the liquid phase exfoliation of graphite in biomass-derived solvents. ADVANTAGE - The process: is scalable and utilizes the solvent that is recyclable and reusable for subsequent processes (claimed); provides the single layer graphene sheets free of contamination and with high electrical conductivity (23.36 Sm-1); utilizes inexpensive and naturally abundant biomass-derived solvents for the exfoliation of low value graphite to produce high value single layer graphene sheets; utilizes the seaweeds (Kappaphycus alvarezii) to produce levulinic acid by hydrolysis, where the seaweed is cultivable and does not need fresh water irrigation unlike terrestrial plants, thus making them abundant for large scale exploitation, and further the seaweeds are bestowed with very good growth rate and can be harvested multiple times unlike other terrestrial plants; and also enables to produce levulinic acid from k-carrageenan extracted from the seaweed. DETAILED DESCRIPTION - Facile production of single layer graphene sheets by liquid phase exfoliation of graphite in biomass-derived solvents, comprises: (i) submerging 0.1-0.15 g of graphite in 20-30 ml of biomass derived solvents comprising levulinic acid; (ii) ultrasonication of the obtained dispersion of graphite in levulinic acid for 60-160 minutes; (iii) keeping the ultrasonicated dispersion for 24 hours at room temperature; (iv) melting the thus formed levulinic acid crystal and centrifuging at 2000-6000 rpm for 20-120 minutes to form graphene sheets; and (v) centrifuging graphite dispersion obtained in step (ii) at 5000 rpm for 1 hour to get single layer graphene sheets.