Patent ID: 8480764

Claim:
A process for obtaining a biofuel consisting of dimethyl furan, by successively dissolving cellulose in a mixture of N-alkyl imidazolium chloride (NAIC), hydrochloric acid 37% and an alcohol, hydrolysing cellulose into the acetal of glucose, evaporating the alcohol and water, dehydrating the glucose acetal to the acetal of hydroxymethyl furfural, adding to the reaction mixture an water solution of sodium chloride, extracting with an alcohol, concentrating the alcohol extract by distillation, mixing the alcohol concentrate with a ketone and a diluted hydrochloric acid solution in order to convert residues of NAI to the corresponding chloride (NAIC), extracting from the ketone phase residues of NAIC by washing several times with water, evaporating the ketone, mixing the concentrate with an alcohol, hydrogenating the almost chloride free alcohol concentrate and isolating the dimethyl furan by distillation.