钒中毒与捕钒剂对催化裂化催化剂性能的影响

Effect of vanadium poisoning and vanadium trapping agent on properties of fluid catalytic cracking catalyst

在黏土和拟薄水铝石制备的微球中按照一定比例加入镁的化合物,酸化后喷雾焙烧制得捕钒剂。采用X-射线荧光光谱仪(XRD),物理吸附仪,扫描电子显微镜(SEM),重油微反等方法,研究了钒对催化剂结构及裂化性能的危害以及该捕钒剂对钒污染的抑制作用。结果表明:捕钒剂最佳的加入量(质量分数)为8%,加入方式为先与催化剂混合;催化剂经过钒污染后添加捕钒剂的样品比表面积、孔容和微反活性都有所提高;在重油微反和固定流化床评价中,加入捕钒剂的样品转化率分别提高了0.92,0.29个百分点,轻质油收率分别提高了3.14,2.30个百分点,液体收率分别提高了3.02,1.55个百分点。

The microballoon was prepared by clay and pseudo -boehmite, adding magnesium com- pound at a certain proportion, and the vanadium trapping agent was obtained by means of acidifica- tion, spray drying and calcinations. The effect of va- nadium on catalyst structures and harm of cracking performance and inhibiting effects of vanadium trap- ping agent on vanadium pollution were investigated by X - Ray diffraction （ XRD ） , BET, scanning electron microscope （SEM）, heavy oil micro reactor and so on. The results showed that the optimum adding quantity of vanadium trapping agent was 8 % （mass fraction）, and the feeding mode was mixing with catalyst first. The catalyst was polluted by vana- dium, then added vanadium trapping agent, and its specific surface area, pore volume and microactivity all improved. In the heavy oil microreactor and fixed fluidized bed evaluation, the conversion of added va- nadium trapping agent increased by 0.92 and 0.29 percent points respectively, the yield of light oil rose by 3.14 and 2.30 percent points separately, and liquid yield improved by 3.02 and 1.55 percent points individually.