Nitration of chlorobenzene by ultrasonic-assisted synthesized sulfated ZrO2 catalyst with NO2

Abstract

Different solid superacid sulfated ZrO 2 (SO 4 2-/ZrO 2 ) samples were successfully prepared by conventional and ultrasonic assisted chemical precipitation process, and then they were characterized by XRD, FT-IR, TGA, BET, NH 3 -TPD and Py-FT-IR. The results indicate that the acidity and surface area of sulfated sample can be increased by using ultrasonic. Furthermore, this ultrasonic-assisted catalyst was used for the chlorobenzene nitration using NO 2 as nitrating agent. The catalyst shows excellent catalytic activity and reusability for the nitration of chlorobenzene giving high para selectivity. Furthermore, the reaction mechanism was proposed by combination of experimental results and theoretical calculations. The present work provides an easy-to-implement, mild and environmentally friendly approach for the e cient preparation of valuable para-nitrochlorobenzene, which has extensive industrial application prospects.

Efficient and high para-selective conversion of toluene with NO2 to para-nitrotoluene in an O2–Ac2O–HβD4 composite catalytic system

“…In the search for nitration agents for nitration processes, nitrogen oxides (NO 2 , N 2 O 4 and N 2 O 5 ), 10–12 nitrate salts 13,14 or acetyl nitrate, 15,16 which are more environmentally benign than nitric acid, were tested. Among them, nitrogen oxides (especially NO 2 ) have unique advantages for nitrification reactions.…”