Abstract: A series of MCM-41 molecular sieves have been prepared on an industrial scale, and the effect of preparation factors such as aging temperature, pH values on the structure and pore distribution of the MCM-41 product have been studied by using X-ray diffraction(XRD), thermogravimetric(TG) and electron microscopy (TEM). It is shown that the pH values have a significant effect on the crystallinity of the synthesized product. Under proper conditions, the MCM-41 prepared on an industrial scale has the same performance as the samples prepared on an Lab-scale. The prepared MCM-41 was used as a modifier of zeolite Y for fluid catalytic cracking (FCC) of residual oil. It is shown that the addition of the MCM-41 in the zeolite Y catalyst increases the pore size, and surface area of the catalysts, which helps to increase the yield of gasoline and diesel and decrease the production of gaseous product and carbon deposition in the catalyst. The better performance of the MCM-41 modified zeolite Y catalyst is believed to be due to its adjustment on the acidity and increase of the pore size.

Key words: MCM-41, Industrial-scale synthesis, FCC catalyst