Patent US4619756A successfully refreshed from Google Patents.
US4619756A
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Method to inhibit deposit formation
Assignee: ExxonMobil Chemical Patents Inc
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Filing: 1985-10-11
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Granted: 1986-10-28
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Expires: 2005-10-11
Abstract
Abstract Deposit formation on the contact surfaces of structures containing heated hydrocarbon fluids such as refinery units, particularly units associated with the distilling process such as preheating stages, is inhibited by incorporating in the feed stock from 0.0001 to 0.01 weight percent of thiophene-containing polycondensed aromatic/naphthenic compounds of number average molecular weight (Mn) from 200 to 1000 and if desired at least one other additive such as an oil-soluble dispersant, antioxidant, antipolymerant, antifoulant and mixtures thereof into said hydrocarbon stream.
Inventors
- 👤 Ghazi B. Dickakian
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 15:06
CPC Classifications
C; C10; C10G; C10G9/00; C10G9/14; C10G9/16; C10L; C10L10/00; C10L10/04
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
49 words
A process for inhibiting deposit formation on the contact surfaces of structures confining heated hydrocarbon fluid which exhibits substantial fouling comprising the step of introducing into said hydrocarbon fluid at least an inhibiting amount of thiophene-containing polycondensed aromatic/naphthenic compounds of number average molecular weight (Mn) from 200 to 1,000.
Claim 2
Dependent Claim
49 words
A process for inhibiting deposit formation on the contact surfaces of structures confining heated hydrocarbon fluid which exhibits substantial fouling comprising the step of introducing into said hydrocarbon fluid at least an inhibiting amount of thiophene-containing polycondensed aromatic/naphthenic compounds of number average molecular weight (Mn) from 200 to 1,000.
Claim 3
Dependent Claim
67 words
A process for preventing heat transfer reduction in a metal conductor through which passes a heated liquid hydrocarbon stream which exhibits substantial fouling comprising the step of introducing into said stream from 0.0001 to 0.01 weight percent, based on the weight of said stream, of oil-soluble, alkylated (C 2 -C 12 ), thiophene-containing, polycondensed aromatic/naphthenic compounds of number average molecular weight (Mn) ranging from 200 to 1000.
Claim 4
Dependent Claim
67 words
A process for preventing heat transfer reduction in a metal conductor through which passes a heated liquid hydrocarbon stream which exhibits substantial fouling comprising the step of introducing into said stream from 0.0001 to 0.01 weight percent, based on the weight of said stream, of oil-soluble, alkylated (C 2 -C 12 ), thiophene-containing, polycondensed aromatic/naphthenic compounds of number average molecular weight (Mn) ranging from 200 to 1000.
Claim 5
Dependent Claim
35 words
A process according to claim 1 wherein said compounds are introduced as a refinery stream containing said compounds having a boiling range within the range of from 200° C. to 550° C. at atmospheric pressure.
Claim 6
Dependent Claim
31 words
A process according to claim 1 wherein there is also introduced with said compounds at least one other oil-soluble additive of the class of dispersants, antioxidants, antipolymerants, antifoulants and mixtures thereof.
Claim 7
Dependent Claim
17 words
A process according to claim 4 wherein said other additive is polyisobutyenyl succinimide of an alkylene polyamine.
Claim 8
Independent Claim
72 words
A method for reducing the fouling of metal surfaces by a heated liquid petroleum stream, which exhibits the formation of undesirable carbonaceous material which markedly reduces heat transfer efficiency comprising introducing into said petroleum stream an inhibiting amount of oil soluble, alkylated (C 2 -C 12 ), thiophene-containing polycondensed aromatic/naphthenic compounds of number average molecular weight ranging from 200 to 1000 and having a boiling range from 200° C. to 550° C.
Claim 9
Independent Claim
72 words
A method for reducing the fouling of metal surfaces by a heated liquid petroleum stream, which exhibits the formation of undesirable carbonaceous material which markedly reduces heat transfer efficiency comprising introducing into said petroleum stream an inhibiting amount of oil soluble, alkylated (C 2 -C 12 ), thiophene-containing polycondensed aromatic/naphthenic compounds of number average molecular weight ranging from 200 to 1000 and having a boiling range from 200° C. to 550° C.
Claim 10
Dependent Claim
20 words
The process according to claim 1 wherein said hydrocarbon fluid comprises crude oil containing less than 50 wt.% total aromatics.
Claim 11
Dependent Claim
17 words
The process according to claim 7 wherein said crude oil contains less than 40 wt.% total aromatics.
Claim 12
Dependent Claim
17 words
The process according to claim 8 wherein said crude oil contains less than 30 wt.% total aromatics.
Claim 13
Dependent Claim
35 words
The process according to claim 4 wherein said thiophene-containing polycondensed aromatic/naphthenic compounds are present in an amount of from 1 to 8 parts by weight per part by weight of the total of aid additive.
Claim 14
Dependent Claim
17 words
The process according to claim 1 wherein said hydrocarbon fluid is heated to less than 400° C.
Claim 15
Dependent Claim
17 words
The process according to claim 2 wherein said hydrocarbon stream is heated to less than 400° C.
Claim 16
Dependent Claim
17 words
The method according to claim 6 wherein said petroleum stream is heated to less than 400° C.
Claim 17
Dependent Claim
16 words
The process according to claim 1 wherein the inhibiting amount is from 0.0001 to 0.5 wt.%.
Claim 18
Dependent Claim
16 words
The process according to claim 14 wherein the inhibiting amount is from 0.0001 to 0.1 wt.%.
Claim 19
Dependent Claim
16 words
The process according to claim 15 wherein the inhibiting amount is from 0.0008 to 0.003 wt.%.
Claim 20
Dependent Claim
44 words
The process according to claim 1 wherein said thiophene-containing polycondensed aromatic/naphthenic compounds are components of a stream characterized as containing 29 to 43% of a saturated fraction, 7 to 56% of a neutral aromatic fraction and 14 to 48% of a polar aromatic fraction.
Claim 21
Dependent Claim
16 words
The process according to claim 2 wherein the number molecular weight ranges from 200 to 300.
Claim 22
Dependent Claim
16 words
The process according to claim 1 wherein an inhibiting amount is from 25 to 100 ppm.
Claim 23
Dependent Claim
42 words
The process according to claim 1 wherein said thiophene-containing polycondensed aromatic/naphthenic compounds are obtained from one or more of thermal cracking of petroleum distillates, catalytic cracking of petroleum distillates, coal liquification, coal gasification, coal carbonization or aromatic extracts from lubricating oil processing.
References Cited (Backward Citations)
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