The development of catalytic cracking technology is closely dependent on the development of catalysts. With the microsphere catalyst, the fluidized bed catalytic cracking unit appeared; the appearance of the molecular sieve catalyst led to the development of the riser catalytic cracking. Product yield, product quality, and economic benefits have a significant impact. Catalytic cracking unit usually consists of three parts, namely reaction-regeneration system, fractionation system and absorption stabilization system. The reaction-regeneration system is the core of the whole device.

The process of catalytic cracking mainly includes three parts: ① catalytic cracking of feedstock oil; ② catalyst regeneration; ③ product separation. The feedstock is injected into the lower part of the riser reactor, where it is mixed with the high temperature catalyst, gasified and reacted. The reaction temperature is 480~530℃, and the pressure is 0.14~0.2MPa (gauge pressure. The reaction oil and catalyst are separated in the settler and the cyclone separator (referred to as the cyclone), and then enter the diverter tower to separate gasoline, diesel oil and heavy oil back to the refinery. .The cracked gas is compressed and then goes to the gas separation system. The coked catalyst is used in the regenerator to burn off the coke with air, and the regeneration temperature is 600~730℃.

Determining the acidity of a catalyst is of great significance. Temperature-programmed desorption (TPD) and infrared spectroscopy (IR) methods are commonly used methods. Combining these two methods can more accurately obtain the acidic characteristics of solid acid catalysts. People mostly use NH3-TPD to measure the amount of acid, and use pyridine-IR to distinguish B acid and L acid. The combination of the two makes the data mismatch due to the difference of probe molecules. How to solve the problem of data matching and how to solve the memory effect of pyridine seems to be a problem. especially important.

After many experiments and improvements, we have developed a non-metallic system adsorption instrument (TP-5080) and a pyridine infrared (IR-TD) device, which makes the desorption of pyridine and pyridine in the system faster, and fundamentally solves the problem of pyridine residues. Taking HZSM-5 and SAPO-34 as examples, using pyridine as the probe molecule, and combining the temperature-programmed desorption data and infrared spectrum data, the experimental results were obtained.