Abstract: The ionic liquid Et₃NHCl-AlCl₃ was used to catalyze the alkylation of diphenyl ether with 1-dodecene to synthesize di-dodecyl diphenyl ether.When the molar ratio of diphenyl ether/1-dodecene was 1∶3 (0.3 mol diphenyl ether),the optimized conditions of alkylation reaction obtained by orthogonal experimental method were catalyst dosage of 0.045 mol,reaction temperature of 70 ℃ and reaction time of 1 h.The conversion of diphenyl ether reaches 98.1% and the selectivity is 33.7% under such optimized conditions.The influences of catalyst structure on its catalytic activity were also investigated by changing the structure of the cationic and anionic parts of ion liquids.The results show that the catalytic activity is determined by the structure of the anion,and the best catalyst is Et₃NHCl-AlCl₃.

Key words: ionic liquid, alkylation reaction, di-alkylated diphenyl ether, Gemini surfactant