2,6-Lutidine Synthesis Over Modified ZSM-5 Catalysts

A review has been accomplished for synthesize 2, 6-lutidine(LUT). On the basis of discussion of advantage and disadvantage of these synthesis methods, synthesizing LUT over modified ZSM-5 catalysts from metHanol, acetone and ammonia is put forward. An apparatus with fix-bed reactor has been built for studying the synthesis of LUT over several catalysts.Some modified ZSM-5 catalysts are investigated, for example HZSM-5, SbZSM-5, CuZSM-5, Sb-CuZSM-5 , LaZSM-5, YZSM-5, MnZSM-5, CoZSM-5, CdZSM-5, Sn27SM-5, RuZSM-5 and so on. Sn2+ZSM~5, YZSM-5 and RuZSM-5 have high catalytic activity. The yields of LUT are 24.8%, 22.2%P 20.3% respectively. Since the main side reactions are the decomposition reactions of methanol and acetone, purifying LUT from the reaction product is facileThe function of oxidative sites in catalysts is investigated. Methanol, acetone and ammonia can synthesize LUT successfully over HZSM-5 catalyst in which no oxidative sites exist. Pretreating the catalyst with H, can hardly reduce the catalytic activityThe catalyst Sn'TZSM-5 is studied. After the reaction having gone for 30. 7h over Sn1+ZSM-5, the deactivation of the catalyst is not observed. And the steady state of tin is Sn2+ during the reaction. The reaction temperature affects the catalytic activity of Sn'1+ZSM-5. The reaction just meets the highest yield of LUT under 560 癈 over Snl+ZSM~5. Another factor that affect the catalytic activity of Sn''ZSM~5 is the quantity of Sn1* loaded onto the ZSM-5. When Sn'1+ZSM-5 is prepared with 0. 3 mol/L aqueous solutions of Sn4+ by ion exchange, it presents the highest catalytic activity.As for the catalyst Sn4+ZSM-5 prepared by ion exchange with 0. 3 mol/L aqueous solutions of Sn4+ and 60-40 mesh HZSM-5(Si/Al=58), the LUT' s mole yield is 35. 0% under the reaction condition of atmospheric pressure, 560 癈 and 2350 rf1 space velocity.