Preparation Technology Of3-Cyanopyridine By Ammoxidation

3-cyanopyridine is an important intermediates for synthesizing of nicotinic acid and nicotinamide, it has an important application in the pharmaceutical industry. The current industrial synthesis method is ammoxidation of3-picoline. Developing one kind of catalyst with high conversion, high yield and long life is the key to this reaction.In this research, through the catalyst screening, optimization of process conditions and design production of5,000-ton per year3-cyanopyridine flow organization and mass balance of the key section, it can complete the preliminary ammoxidation of3-cyanopyridine industrializationK additives was introduced to the vanadium-based catalysts for the first time, by screening the vanadium catalysts, the results show:with a load capacity of17%vanadium, V:K:Mo:P=1:0.012:0.011:0.009(atomic molar ratio), use this catalyst for catalytic reaction, the catalyst has good performance, with55days continuous stability test, the conversion of3-picoline is99.9%, the yield of3-cyanopyridine is88.4%. The different K content catalysts and the best catalysts were characterized by specific surface area and pore structure analysis, SEM, XRD, NH3-TPD, H2-TPR, the results show the good performance is owing to the active component is highly fragmented on the carrier, the suitable surface area and pore structure, appropriate acidity and reducibility.By evaluating the performance of the best catalyst, the effects of the reaction temperature, feed ratio and volume space velocity on the catalytic activity were detected. The results show that when the reaction temperature is310℃,3-picoline: oxygen:ammonia:water=1:2.95:1.9:5(molar ratio), the volume space velocity is2096h-1, the conversion of3-picoline is98.6%, the yield of3-cyanopyridine is92.3%.Through design production of5,000-ton per year3-cyanopyridine flow organization and mass balance of the key section, obtained a preliminary design of a cost-effective process.