Method for recovering reforming catalyst, catalyst and adsorbent

Abstract

A method for recovering reforming catalyst comprises obtaining spent reforming catalysts; immersing the spent reforming catalysts with different degrees of aging into a light solution to obtain immersed catalysts and allowing the light solution to enter pores in the spent reforming catalysts to lower a pseudo-skeletal density of each spent reforming catalyst to obtain immersed catalysts; immersing the immersed catalysts into a heavy solution that has a density greater than pseudo-skeletal density of the immersed catalysts and replacing the light solution in the pores in the immersed catalysts by the heavy solution to increase density of the immersed catalysts; and awaiting the immersed catalysts to settle in the heavy solution to obtain settled catalysts, wherein different settling velocities due to aging creates layers of settled catalysts. Therefore, the reforming catalysts with different degrees of aging are easily classified into different layers, which can be reused for cost saving.

Description

BACKGROUND OF THE INVENTION[0001]1. Field of Invention[0002]The present invention relates to a method for recovering reforming catalyst and more particularly to a method for classifying used catalysts with different degrees of aging, so reforming catalysts with a low degree of aging are collected easily to be recovered and reused.[0003]2. Description of the Related Art[0004]Catalytic reforming procedure is a main procedure in secondary processing of feed oil and is used to produce ingredients for gasoline, aromatic hydrocarbons and hydrogen cheaply in petroleum refineries. Catalytic reforming procedure categories include three kinds of reforming processes depending on processes for reforming catalysts, including a semi-regeneration reforming process, a continuous catalytic reforming process and a cyclic catalytic reforming process. In related industry, above processes are used in a proportion of 6:3:1. Now most new units adopt continuous catalytic reforming process.[0005]The continu...

AI Technical Summary

Benefits of technology

"The present invention provides a method for easily classifying used catalysts based on their degree of aging. This allows for the collection and reuse of less aged catalysts, saving costs. The method involves immersing the catalysts in a light solution to lower their pseudo-skeletal density, and then immersing them in a heavy solution to increase their pseudo-skeletal density. The settled catalysts are then layered due to different settling velocities. Overall, this method allows for easy classification and recovery of used catalysts."

Problems solved by technology

However, total surface area of the used catalysts will be gradually decreased as the catalysts are used multiple times, so an operational life of the catalysts will be reduced.

Furthermore, phase form of aluminum oxide (Al2O3) support also affects the total surface area.

However, when a total output value of catalytic reformers decreases because properties of the catalysts are less preferential, a lost output value is more expensive than cost of the fresh catalysts.

But units have troubles sometimes, some catalysts may be more severely aging due to unusual operation conditions such as hot spot in certain area of catalyst cycle system.

Economic benefits of the catalytic reformers will be affected if the catalysts are not substituted correctly.

However, the particle sizes or the densities between reforming catalysts with different degrees aged do not present significant differences, so the reforming catalysts cannot be easily and effectively classified.

However, because reforming catalyst has large pores and most liquid solution is easily filled in the pores of the reforming catalyst and a solution with a density greater than the density of γ-form Al2O3 (3.97 g / cm3) is not easy obtained, especially without negative effect after separation.

Therefore, this method cannot be used for separating reforming catalysts.

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