Vapour phase synthesis of 3,5-dipropylpyridine over modified zeolites

A study on the conversion of glycerol to pyridine bases over Cu/HZSM-5 catalysts

“…, and Ni(NO 3 ) 2 •6H 2 O (98%)] and other reagents used to prepare the catalysts were obtained from KRS Chemical Reagent Cooperation, Tianjin, China. HZSM-5 with different Si/Al ratios (Si/Al = 25, 38, 50, 80 and 117), abbreviated as [HZSM-5 (25), HZSM-5 (38), HZSM-5 (50), HZSM-5(80) and HZSM-5(117)], and mordenite zeolite were provided by Nankai University Catalyst Plant, Tianjin, China. γ-Al 2 O 3 (99.5%) and SiO 2 were purchased from the Tianjin Research and Design Institute of Chemical Industry, Tianjin, China.…”

“…All the catalysts were prepared via the wet impregnation method. For example, 4.8 g of Cu(NO 3 ) 2 •3H 2 O was dissolved in 11.5 g of water, and then 19.9 g of HZSM-5 (38) with a diameter of 2 mm and a length of 2.5 mm was introduced into the solution. The obtained mixture was vigorously stirred at room temperature for 48 h and then allowed to dry in an oven at 110 °C for 6 h. The obtained catalyst precursor was calcined at 550 °C for 6 h to obtain the 4.6% Cu/HZSM-5 (38) catalyst (the subscript represents the copper content in the catalyst).…”

Enhanced selectivity in the conversion of glycerol to pyridine bases over HZSM-5/11 intergrowth zeolite

“…The optimal temperature was 520 C from the view point of total yield of pyridine bases, which was same as that of the reaction over 4.6% Cu/HZSM-5 catalyst, 6 higher than the ones for the synthesis of pyridine bases from other raw materials. 15,16,18,20,[28][29][30][31][32] The high temperature in the synthesis of pyridine bases from glycerol compared to other feed stocks can be attributed to the high energy requirement for the generation of acetaldehyde of and formaldehyde from acetol and 3-hydroxypropanal. Acetaldehyde and formaldehyde are also key intermediates in the transformation of glycerol to pyridine bases in addition to acrolein.…”

Synthesis of N-heterocyclic compounds over zeolite molecular sieve catalysts: an approach towards green chemistry

“…Srinivas et al 45 reported the synthesis of 3,5-dipropyl pyridine using valeraldehyde, formaldehyde and ammonia over modified ZSM-5 catalysts. The ZSM-5 zeolite was modified with various metal ions such as Co, Ni, Pb, La, and Zr.…”