Modified Y molecular sieve

Abstract

The invention discloses a modified Y molecular sieve, which is prepared by performing a primary exchange reaction on a NaY molecular sieve and rare earth solution, then introducing a phosphorus compound into an exchange serous fluid for further reaction, filtering and washing the mixture after the reaction, and roasting a filter cake under a vapor condition. The lattice constant of the modified Y molecular sieve is 2.450 to 2.479 nanometers, and the modified Y molecular sieve comprises the following components in percentage by weight: 2.0 to 6.0 percent of sodium oxide, 0.01 to 2.5 percent of phosphorus and 11 to 23 percent of rare earth oxide. Most of the rare earth of the modified molecular sieve is positioned in a sodalite cage of the Y molecular sieve, so the stability of the molecular sieve in a high-temperature hydrothermal environment is increased; and the structural acidity of the molecular sieve plays a good role in modulation. The modified Y molecular sieve used as an active component of a cracking catalyst has strong heavy oil conversion capacity and good coke selectivity.

Description

technical field [0001] The present invention relates to a modified Y molecular sieve, and more specifically relates to a "cross-baked" rare earth and phosphorus composite modified Y molecular sieve. Background technique [0002] In recent years, with the increasing difficulty of oil extraction, the trend of heavy crude oil in the world is very obvious. While the quality of crude oil is getting heavier and worse, the world's demand for light oil products is increasing day by day. The reserves of heavy oil and conventional crude oil account for 53% and 25% respectively in the world. The vast majority of crude oil in my country also belongs to heavy crude oil. The yield of heavy oil above 350°C accounts for more than 70% of crude oil. In addition, FCC process blending The proportion of residual oil is also increasing, and residual oil catalytic cracking (RFCC) is playing an increasingly important role in heavy oil conversion. Residual oil not only contains macromolecular compou...

AI Technical Summary

Problems solved by technology

However, the disadvantage of the existing technology is that the modification process is complex, such as the super-stabilization of molecular sieves and the phosphorus modification process are carried out in a distributed manner, the production cycle is long, and the utilization rate of rare earths is not high; High activity and good coke selectivity at the same time