US 4,399,051 AGranted

Method for regeneration of rhodium-containing catalyst

OwnerGeorgy L. Rabinovich, Zoya P. Lukina +2inventors

InventorsGeorgy L. Rabinovich, Zoya P. Lukina, Kira L. Volkova, Viktor N. Mozhaiko

Life of this patent

Estimating the term…

Loading patent…

Abstract

A method for regenerating of rhodium-containing catalysts exhausted and sulphur-poisoned in the course of dealkylating alkyl benzenes or mixture thereof with steam or hydrogen, comprising the steps of burning out coke deposits by an oxygen-containing gas and chlorinating the catalyst with chlorine or with a chlororganic compound in a flow of hydrogen, an inert gas or a mixture of an inert gas with oxygen and moisture. The catalyst is additionally treated with ammonia or with a nitrogen-containing compound capable of decomposing under the treatment to yield ammonia in the presence of at least one component selected from the group consisting of: water, hydrogen, and nitrogen-oxygen mixture. The treatment can be conducted both in the liquid and the gaseous phases at temperatures ranging between 20.degree. and 650.degree. C. and at a pressure between 1 and 50 atm. The present invention can be used for regeneration of rhodium-containing catalysts and used for dealkylating alkyl benzenes with steam or hydrogen.

Claims8

Dependent claims

A method for regenerating a sulfur poisoned rhodium-containing catalyst used for dealkylating alkyl benzenes with steam or hydrogen, consisting essentially of the steps of:

burning out carbon deposits with an oxygen-containing gas;
chlorinating the catalyst, in a flow of gas selected from the group consisting of hydrogen, an inert gas, or a mixture of an inert gas with oxygen and moisture, with a chlorinating compound selected from the group consisting of chlorine or a chlororganic compound;
and
treating the catalyst at a temperature of from 20.degree. to 650.degree. C., and a pressure of from 1 to 50 atm, for 0.5 to 48 hours with a nitrogen-containing compound selected from the group consisting of an aqueous ammonia solution, gaseous ammonia, or a nitrogen-containing compound which decomposes under the treatment conditions to yield ammonia;
wherein the treatment with ammonia in the gaseous phase is conducted in the presence of at least one component selected from the group consisting of:
steam, water, hydrogen, a nitrogen-oxygen mixture, and an oxygen-inert gas mixture.

3 more elements

Dependencies are inferred from the claim text.