Classifications

• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10G—CRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
  • C10G7/00—Distillation of hydrocarbon oils
  • C10G7/10—Inhibiting corrosion during distillation
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10G—CRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
  • C10G75/00—Inhibiting corrosion or fouling in apparatus for treatment or conversion of hydrocarbon oils, in general
  • C10G75/02—Inhibiting corrosion or fouling in apparatus for treatment or conversion of hydrocarbon oils, in general by addition of corrosion inhibitors
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10G—CRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
  • C10G9/00—Thermal non-catalytic cracking, in the absence of hydrogen, of hydrocarbon oils
  • C10G9/14—Thermal non-catalytic cracking, in the absence of hydrogen, of hydrocarbon oils in pipes or coils with or without auxiliary means, e.g. digesters, soaking drums, expansion means
  • C10G9/16—Preventing or removing incrustation

Definitions

• the present invention relates to the field of the treatment of acidic crude oils in refineries. More specifically, it relates to a process for combating corrosion of refining units which process acid crudes, comprising the use of specific sulfur compounds. Petroleum refineries can face a serious corrosion problem when they have to process certain so-called acid crudes. These crude acids essentially contain naphthenic acids which are at the origin of this very particular corrosion phenomenon, since it occurs in a liquid medium which does not conduct electric current. These naphthenic acids correspond to saturated cyclic hydrocarbons carrying one or more carboxylic groups. The acidity of a crude oil is described by a standardized measurement according to standard ASTM D 664-01.
• TAN Total Acid Number
• patent EP 742277 describes the inhibitory action of a combination of a trialkyl phosphate and an organic polysulfide.
• US patent 5552085 recommends the use of thiophosphorus compounds such as organo thiophosphates or thiophosphites.
• the patent AU 693975 discloses as an inhibitor a mixture of trialkyl phosphate and phosphoric esters of sulfurized phenol neutralized with lime.
• organophospores are very delicate to handle, due to their high toxicity. They are also poisons for hydrotreatment catalysts installed to purify hydrocarbon fractions from atmospheric and vacuum distillations. For these two reasons at least, their use in the refining field is not desirable.
• the subject of the invention is therefore a process for combating corrosion by naphthenic acids of the metal walls of a refining unit, characterized in that it comprises the addition to the hydrocarbon stream to be treated by the unit d '' an effective amount of a compound of formula:
• HS-B-COOR (I) in which: - B represents a bivalent saturated hydrocarbon radical which can be either acyclic, in linear or branched form, or cyclic, and which contains from 1 to 18 carbon atoms, preferably from 1 to 4; and - R represents a hydrogen atom, or an alkali or alkaline earth metal, or an ammonium group, or an alkyl radical (linear or branched), cycloalkyl, aryl, alkylaryl or arylalkyl, said radical containing from 1 to 18 atoms carbon, preferably 1 to 10, and optionally one or more heteroatoms.
• thioglycolic acid of formula HS-CH 2 -COOH, or one of its esters, preferably an aliphatic ester, is used as compound of formula (I).
• 2-ethyl hexyl thioglycolate, isooctyl thioglycolate or methyl thioglycolate are used.
• the quantity of compound of formula (I) to be added to the hydrocarbon stream to be treated by the refining unit generally corresponds to a concentration (expressed in equivalent weight of sulfur) of said compound relative to the weight of the hydrocarbon stream, which can range from 10 to 5000 ppm, preferably from 50 to 500 ppm.
• the method according to the invention advantageously makes it possible to treat hydrocarbon streams, in particular crude oils, whose TAN is greater than 0.2, and preferably greater than 2.
• the process implementation temperature corresponds to that at which the corrosion reactions with naphthenic acids occur, and is generally between 200 and 450 ° C, and more particularly between 250 and 350 ° C.
• the addition of the compound of formula (I) in the hydrocarbon stream can be carried out either at the very entrance of the unit (simultaneously with the hydrocarbon stream to be treated), for an overall treatment of corrosion, or in the part of the unit where the corrosion reaction takes place, for localized treatment.
• metal walls of the refining unit means all the walls capable of being in contact with the stream of acidic hydrocarbon to be treated.
• This test uses an iron powder simulating a metal surface, and a mineral oil in which is dissolved a mixture of naphthenic acids, simulating a stream of acid crude.
• the characteristics of these reagents are as follows: - white mineral oil having a density of 0.838 - powder of spherical iron particles, with a particle size of -40 + 70 mesh (i.e. approximately 212 to 425 ⁇ m) - mixture of naphthenic acids having from 10 to 18 carbon atoms, a boiling point between 270 and 324 ° C and an average molar mass of 244 g / mol.
• the following are introduced into a 150 ml glass reactor, equipped with a dropping funnel and a water cooler, and provided with a stirring and temperature measurement system: - 70 ml (i.e. 58.8 g) mineral oil, - 2 g of iron powder, - 2.8 g of the mixture of naphthenic acid.
• the initial TAN of the reaction mixture is equal to 10.
• These reagents are kept in contact for 2 hours at a temperature of 250 ° C., under an atmosphere of dry nitrogen to avoid oxidation reactions.
• the concentration of dissolved iron in the medium is determined by a conventional method implementing a mineralization of a sample, taking up the residue in acidified water and dosing by a plasma torch. . This concentration of dissolved iron (expressed in ppm) is directly proportional to the rate of corrosion of the iron powder generated by the mixture of naphthenic acids present in the mineral oil.
• Example 2 Tests in the Presence of Thioglycolic Acid Derivatives Example 1 is repeated by adding to the mineral oil compounds of formula (I) derived from thioglycolic acid when the reactor is charged. The content of these derivatives is calculated so as to obtain a corresponding concentration of 500 ppm by mass of sulfur in the mineral oil present in the reactor. The results obtained in Table II below are obtained. The table also shows the rate of inhibition of corrosion caused by the mixture of naphthenic acid.
• Example 2 is repeated, replacing the thioglycolic acid derivatives with methyl mercaptopropionate at a content also corresponding to 500 ppm of sulfur in the medium.
• An iron concentration equal to 118 ppm is measured at the end of the test, ie an inhibition rate of 42%.

Landscapes

• Chemical & Material Sciences (AREA)
• Oil, Petroleum & Natural Gas (AREA)
• Engineering & Computer Science (AREA)
• Chemical Kinetics & Catalysis (AREA)
• General Chemical & Material Sciences (AREA)
• Organic Chemistry (AREA)
• Physics & Mathematics (AREA)
• Thermal Sciences (AREA)
• Production Of Liquid Hydrocarbon Mixture For Refining Petroleum (AREA)
• Preventing Corrosion Or Incrustation Of Metals (AREA)
• Liquid Carbonaceous Fuels (AREA)

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• 2003
  • 2003-07-07 FR FR0308250A patent/FR2857372B1/fr not_active Expired - Fee Related
• 2004
  • 2004-06-25 EA EA200600194A patent/EA009208B1/ru not_active IP Right Cessation
  • 2004-06-25 KR KR1020067000381A patent/KR20060032194A/ko not_active Ceased
  • 2004-06-25 CN CNB2004800192928A patent/CN100556991C/zh not_active Expired - Fee Related
  • 2004-06-25 WO PCT/FR2004/001608 patent/WO2005014758A1/fr not_active Ceased
  • 2004-06-25 JP JP2006518258A patent/JP4607870B2/ja not_active Expired - Fee Related
  • 2004-06-25 AU AU2004263692A patent/AU2004263692B2/en not_active Ceased
  • 2004-06-25 CA CA002531824A patent/CA2531824A1/fr not_active Abandoned
  • 2004-06-25 EP EP04767456A patent/EP1654338A1/fr not_active Withdrawn
  • 2004-06-25 US US10/563,549 patent/US7491318B2/en not_active Expired - Fee Related
  • 2004-06-25 BR BRPI0412442-1A patent/BRPI0412442A/pt not_active IP Right Cessation
  • 2004-06-25 MX MXPA06000273A patent/MXPA06000273A/es active IP Right Grant
  • 2004-06-25 UA UAA200600269A patent/UA85057C2/ru unknown
• 2006
  • 2006-01-06 ZA ZA200600174A patent/ZA200600174B/xx unknown
  • 2006-02-03 NO NO20060567A patent/NO20060567L/no not_active Application Discontinuation

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