In the fluidized catalytic cracking (FCC) unit of oil refinery, the attrition resistance of FCC catalysts is affected by particle shape. Although some sophisticated methods, such as Fractal dimension and Fourier analysis, have been introduced to particle shape analysis, most of them are used to assess the shape of individual particle. It is difficult to be used as a means of powder quality control in the course of application and production of FCC catalysts. So three shape factors, i.e. Short/long ratio (S), Roundness (R) and Concavity (C), are applied to characterize them in three different aspects.
A small quantity of FCC catalyst powders were spread on a glass slide M and a thin layer of glue was spread on another glass slide N, then all the particles on slide M were sprinkled on slide N by vibrating manually up and down, in the meantime moving back and forth more than 10 times.