Active coating system for reducing or eliminating coke build-up during petrochemical processes

Abstract

The invention relates to an active coating for reducing or eliminating the build-up of coke deposits on a metal surface of a reactor component. The coating comprises a catalyst system and an adhesion/activation promoter. The catalyst system comprises at least a first compound and a second compound. The first compound is selected from one of the following groups of compounds: (a) a Group IA metal salt, (b) a Group IIA metal salt, and (c) a rare earth metal oxide, and the second compound is selected from a different group from the first compound. The adhesion/activation promoter comprises at least a first oxide and a second oxide. The first oxide is selected from one of the following groups of oxides: (d) a Group IIA oxide, (e) a Group IIIA oxide, and (f) a Group IVA oxide, and the second oxide is selected from a different group from the first oxide. In a preferred embodiment, the catalyst system comprises a Group IA metal salt, a Group IIA metal salt and a rare earth metal oxide, and the promoter comprises a Group IIA oxide, a Group IIIA oxide and a Group IVA oxide. Also disclosed is a method for protecting the inner surfaces of reactor components, such as radiant tubes, fittings and reaction vessels, from coking and corrosion by coating the inner surfaces with the active coating.

We claim:  
     
         1 . An active coating for reducing or eliminating the build-up of coke deposits on a metal surface of a reactor component, the active coating comprising: 
 a catalyst system comprising at least a first compound and a second compound, the first compound being selected from one of the following groups of compounds: (a) a Group IA metal salt, (b) a Group IIA metal salt, and (c) a rare earth metal oxide, and the second compound being selected from a different group from the first compound; and    an adhesion/activation promoter comprising at least a first oxide and a second oxide, the first oxide being selected from one of the following groups of oxides: (d) a Group IIA oxide, (e) a Group IIIA oxide, and (f) a Group IVA oxide, and the second oxide being selected from a different group from the first oxide.    
     
     
         2 . The active coating of  claim 1 , wherein the catalyst system catalyzes the gasification of carbonaceous material and the promoter acts as a binder for the catalyst system and as an adhesive to adhere the catalyst system to the metal surface of the reactor component.  
     
     
         3 . The active coating of  claim 1 , wherein the catalyst system comprises a third compound selected from any one of the groups: (a), (b) and (c).  
     
     
         4 . The active coating of  claim 1 , wherein the promoter comprises a third oxide selected from any one of the groups: (d), (e) and (f).  
     
     
         5 . The active coating of  claim 3 , wherein the first compound is the Group IA metal salt, the second compound is the Group IIA metal salt and the third compound is the rare earth metal oxide.  
     
     
         6 . The active coating of  claim 4 , wherein the first oxide is the Group IIA oxide, the second oxide is the Group IIIA oxide and the third oxide is the Group IVA oxide.  
     
     
         7 . The active coating of  claim 1 , wherein the Group IA metal salt is potassium carbonate, the Group IIA metal salt is magnesium aluminum oxide and the rare earth metal oxide is cerium oxide.  
     
     
         8 . The active coating of  claim 1 , wherein the Group IIA oxide is barium oxide, the Group IIIA oxide is aluminum oxide and the Group IVA oxide is silicon oxide.  
     
     
         9 . The active coating of  claim 1 , wherein a ratio of the catalyst system to the adhesion/activation promoter is from about 1:1 to about 1:5 based on weight.  
     
     
         10 . The active coating of  claim 9 , wherein a ratio of the catalyst system to the adhesion/activation promoter is about 1:3 based on weight.  
     
     
         11 . The active coating of  claim 1 , wherein the catalyst system comprises from about 60% to about 87% by weight of the first compound and from about 13% to about 40% by weight of the second compound based on the total weight of the catalyst system.  
     
     
         12 . The active coating of  claim 11 , wherein the first compound is the Group IA metal salt and the second compound is the rare earth metal oxide.  
     
     
         13 . The active coating of  claim 12 , wherein the Group IA metal salt is potassium carbonate and the rare earth metal oxide is cerium oxide.  
     
     
         14 . The active coating of  claim 1 , wherein the promoter comprises from about 20% to about 50% by weight of the first oxide and from about 50% to about 80% by weight of the second oxide based on the total weight of the promoter.  
     
     
         15 . The active coating of  claim 14 , wherein the first oxide is the Group IIA oxide and the second oxide is the Group IVA oxide.  
     
     
         16 . The active coating of  claim 15 , wherein the Group IIA oxide is barium oxide and the Group IVA oxide is silicon oxide.  
     
     
         17 . The active coating of  claim 3 , wherein the catalyst system comprises from about 20% to about 55% by weight of the first compound, from about 20% to about 40% by weight of the second compound and from about 13% to about 40% by weight of the third compound based on the total weight of the catalyst system.  
     
     
         18 . The active coating of  claim 17 , wherein the first compound is the Group IA metal salt, the second compound is the Group IIA metal salt and the third compound is the rare earth metal oxide.  
     
     
         19 . The active coating of  claim 17 , wherein the catalyst system comprises from about 30% to about 53% by weight of the first compound, from about 30% to about 34% by weight of the second compound and from about 13% to about 40% by weight of the third compound based on the total weight of the catalyst system.  
     
     
         20 . The active coating of  claim 19 , wherein the first compound is the Group IA metal salt, the second compound is the Group IIA metal salt and the third compound is the rare earth metal oxide.  
     
     
         21 . The active coating of  claim 4 , wherein the promoter comprises from about 10% to about 40% by weight of the first oxide, from about 5% to about 50% by weight of the second oxide and from about 30% to about 50% by weight of the third oxide based on the total weight of the promoter.  
     
     
         22 . The active coating of  claim 21 , wherein the first oxide is the Group IIA oxide, the second oxide is the Group IIIA oxide and the third oxide is the Group IVA oxide.  
     
     
         23 . The active coating of  claim 21 , wherein the promoter comprises from about 12% to about 36% by weight of the first oxide, from about 32% to about 48% by weight of the second oxide and from about 32% to about 42% by weight of the third oxide based on the total weight of the promoter.  
     
     
         24 . The active coating of  claim 23 , wherein the first oxide is the Group IIA oxide, the second oxide is the Group IIIA oxide and the third oxide is the Group IVA oxide.  
     
     
         25 . The active coating of  claim 18 , wherein the promoter comprises from about 10% to about 40% by weight of the Group IIA oxide, from about 5% to about 50% by weight of the Group IIIA oxide and from about 30% to about 50% by weight of the Group IVA oxide based on the total weight of the promoter.  
     
     
         26 . The active coating of  claim 18 , wherein the promoter comprises from about 12% to about 36% by weight of the Group IIA oxide, from about 32% to about 48% by weight of the Group IIIA oxide and from about 32% to about 42% by weight of the Group IVA oxide based on the total weight of the promoter.  
     
     
         27 . The active coating of  claim 20 , wherein the promoter comprises from about 10% to about 40% by weight of the Group IIA oxide, from about 5% to about 50% by weight of the Group IIIA oxide and from about 30% to about 50% by weight of the Group IVA oxide based on the total weight of the promoter.  
     
     
         28 . The active coating of  claim 20 , wherein the promoter comprises from about 12% to about 36% by weight of the Group IIA oxide, from about 32% to about 48% by weight of the Group IIIA oxide and from about 32% to about 42% by weight of the Group IVA oxide based on the total weight of the promoter.  
     
     
         29 . An active coating for reducing or eliminating the build-up of coke deposits on a metal surface of a reactor component, the active coating comprising: 
 a catalyst system comprising from about 20% to about 55% by weight of potassium carbonate, from about 20% to about 40% by weight of magnesium aluminum oxide and from about 13% to about 40% by weight of cerium oxide based on the total weight of the catalyst system; and    an adhesion/activation promoter comprising from about 10% to about 40% by weight of barium oxide, from about 5% to about 50% by weight of aluminum oxide and from about 30% to about 50% by weight of silicon oxide based on the total weight of the promoter.    
     
     
         30 . The active coating of  claim 29 , wherein a ratio of the catalyst system to the adhesion/activation promoter is from about 1:1 to about 1:5 based on weight.  
     
     
         31 . The active coating of  claim 30 , wherein a ratio of the catalyst system to the adhesion/activation promoter is about 1:3 based on weight.  
     
     
         32 . An active coating for reducing or eliminating the build-up of coke deposits on a metal surface of a reactor component, the active coating comprising: 
 a catalyst system comprising from about 30% to about 53% by weight of potassium carbonate, from about 30% to about 34% by weight of magnesium aluminum oxide and from about 13% to about 40% by weight of cerium oxide based on the total weight of the catalyst system; and    an adhesion/activation promoter comprising from about 12% to about 36% by weight of barium oxide, from about 32% to about 48% by weight of aluminum oxide and from about 32% to about 42% by weight of silicon oxide based on the total weight of the promoter.    
     
     
         33 . The active coating of  claim 32 , wherein a ratio of the catalyst system to the adhesion/activation promoter is from about 1:1 to about 1:5 based on weight.  
     
     
         34 . The active coating of  claim 33 , wherein a ratio of the catalyst system to the adhesion/activation promoter is about 1:3 based on weight.  
     
     
         35 . The active coating of  claim 1 , wherein the active coating is mixed with water or other suitable solvent to form a slurry.  
     
     
         36 . The active coating of  claim 35 , wherein the slurry is applied to the metal surface of the reactor component.  
     
     
         37 . The active coating of  claim 36 , wherein the slurry is applied by a method selected from the group consisting of sponging, painting, centrifuging, spraying and dipping fill-up technique.  
     
     
         38 . The active coating of  claim 36 , wherein the reactor component is a component that is susceptible to coke formation thereon.  
     
     
         39 . The active coating of  claim 38 , wherein the reactor component is selected from the group consisting of a furnace, a tube fitting, a reaction vessel, and a radiant tube.  
     
     
         40 . A method for reducing or eliminating the build-up of coke deposits during a petrochemical process, comprising: 
 applying a slurry of the active coating of  claim 1  to the metal surface of the reactor component, wherein the coating bonds thereto.    
     
     
         41 . A method for reducing or eliminating the build-up of coke deposits during a petrochemical process, comprising: 
 applying a slurry of the active coating of  claim 29  to the metal surface of the reactor component, wherein the coating bonds thereto.    
     
     
         42 . A method for reducing or eliminating the build-up of coke deposits during a petrochemical process, comprising: 
 applying a slurry of the active coating of  claim 32  to the metal surface of the reactor component, wherein the coating bonds thereto.    
     
     
         43 . The method of  claim 40 , wherein the coating is applied by at least one of sponging, painting, centrifuging, spraying and by dipping/fill-up techniques.  
     
     
         44 . The method of  claim 40 , wherein the coating is from about 25 to about 50 microns thick.  
     
     
         45 . The method of  claim 40 , wherein the petrochemical process is a hydrocarbon cracking process.  
     
     
         46 . The method of  claim 40 , wherein the reactor component is a component that is susceptible to coke formation thereon.  
     
     
         47 . The method of  claim 40 , wherein the reactor component is selected from the group consisting of a furnace, a tube fitting, a reaction vessel, and a radiant tube.