[go: up one dir, main page]

US20020157991A1 - Disaggregation of asphaltenes in incompatible petroleum oil mixtures - Google Patents

Disaggregation of asphaltenes in incompatible petroleum oil mixtures Download PDF

Info

Publication number
US20020157991A1
US20020157991A1 US09/818,435 US81843501A US2002157991A1 US 20020157991 A1 US20020157991 A1 US 20020157991A1 US 81843501 A US81843501 A US 81843501A US 2002157991 A1 US2002157991 A1 US 2002157991A1
Authority
US
United States
Prior art keywords
asphaltene
equation
intensity
aggregates
incompatibility
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Abandoned
Application number
US09/818,435
Other languages
English (en)
Inventor
Thomas Mason
Min Lin
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
ExxonMobil Technology and Engineering Co
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Priority to US09/818,435 priority Critical patent/US20020157991A1/en
Assigned to EXXONMOBIL RESEARCH & ENGINEERING CO. reassignment EXXONMOBIL RESEARCH & ENGINEERING CO. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: LIN, MIN YUE, MASON, THOMAS G.
Priority to PCT/US2002/005231 priority patent/WO2002076889A1/en
Priority to MXPA03007847A priority patent/MXPA03007847A/es
Priority to EP02707839A priority patent/EP1401768A4/en
Priority to CA002439304A priority patent/CA2439304A1/en
Priority to JP2002576157A priority patent/JP2004532302A/ja
Priority to TW091103327A priority patent/TWI238188B/zh
Priority to ARP020100695A priority patent/AR032874A1/es
Publication of US20020157991A1 publication Critical patent/US20020157991A1/en
Priority to US10/699,232 priority patent/US7029570B2/en
Abandoned legal-status Critical Current

Links

Images

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N23/00—Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00
    • G01N23/20—Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00 by using diffraction of the radiation by the materials, e.g. for investigating crystal structure; by using scattering of the radiation by the materials, e.g. for investigating non-crystalline materials; by using reflection of the radiation by the materials
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
    • G01N33/26—Oils; Viscous liquids; Paints; Inks
    • G01N33/28—Oils, i.e. hydrocarbon liquids
    • G01N33/2823—Raw oil, drilling fluid or polyphasic mixtures
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T436/00—Chemistry: analytical and immunological testing
    • Y10T436/21—Hydrocarbon
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T436/00—Chemistry: analytical and immunological testing
    • Y10T436/24—Nuclear magnetic resonance, electron spin resonance or other spin effects or mass spectrometry

Definitions

  • the present invention relates to the disaggregation of asphaltenes.
  • the present invention includes a method to determine aggregation and steps to disaggregate the asphaltenes.
  • Asphaltenes are a fraction of a petroleum oil or refinery process stream that typically aggregate or precipitate out of solution when a nonpolar solvent, petroleum oil, or process stream is mixed or blended with it.
  • Asphaltenes represent a wide variety of hydrocarbon molecules that are typically polyaromatic in nature with some degree of alkylation present and which may or may not contain heteroatoms such as oxygen, nitrogen, and sulfur and metal atoms in their structures.
  • Asphaltenes are usually found in significant quantities in heavy crude oils and refinery residua, and they are believed to sometimes sell-assemble into colloidal micelle-like structures of several molecules that remain thermally suspended in solution due to their small size and possible solvating effects of other types of molecules in the petroleum oil or process stream.
  • asphaltene particles These micelle-like structures of several molecules are sometimes referred to as “asphaltene particles” in order to differentiate them from the single “asphaltene molecules” that may also be present in suspension in the oil.
  • the asphaltene particles are typically smaller than twenty nanometers in size, but this can vary depending upon the source of the petroleum oil or process stream and their concentration in the oil.
  • asphaltene aggregate refers to the formation of larger precipitated clusters of asphaltene particles and molecules that stick together due to an attractive interaction that has been introduced when the nonpolar petroleum oil and/or refinery process stream is blended into the oil containing the suspended asphaltenes.
  • asphaltene aggregates are typically a micron in size and are sometimes large enough to be observed with the unaided naked eye. These aggregates are also typically more dense than the surrounding oil mixture from which they precipitated, so they tend to slowly sediment.
  • oils are said to be incompatible as opposed to compatible oils that do not precipitate asphaltenes on blending.
  • Precipitated asphaltenes are not desirable as they are known to foul process equipment when rapidly heated to high temperatures.
  • the present invention is a method to disaggregate asphaltenes in petroleum oil mixtures by mild heating.
  • a preferred embodiment of the invention determines the presence of aggregated and unaggregated asphaltenes by irradiating the mixture with neutrons and determining the extent of small angle neutron scattering as a function of wavenumber.
  • the solid lines are fits to Equation (1) to be described later in the specification.
  • the solid lines are fits to Equation (1).
  • FIG. 3 shows the low-q scattering intensity associated with the Lorentzian term, I L , of Eq. (1) as a function of mixing volume fraction, ⁇ m , for Souedie/Forties crude oil mixtures, as obtained from fitting the data in FIG. 1.
  • FIG. 4 shows the low-q scattering intensity associated with the Lorentzian term, I L , of Equation (1) as a function of mixing volume fraction, ⁇ m , for BCF-22/Marib Light crude oil mixtures, as obtained by fitting the data in FIG. 2.
  • FIG. 5 shows the low-q scattering intensity, I surf , associated with surface scattering from asphaltene aggregates of Equation (1) as a function of mixing volume fraction, ⁇ m , for Souedie/Forties crude oil mixtures, as obtained by fitting the data in FIG. 1.
  • FIG. 6 shows the power law exponent associated with surface scattering from asphaltene aggregates, ⁇ , of Equation (1) as a function of mixing volume fraction, ⁇ m , for Souedie/Forties crude oil mixtures, as obtained by fitting the data in FIG. 1.
  • the value of ⁇ is essentially the absolute value of the slope of I(q) on a log-log plot in the low q limit.
  • FIG. 7 shows the volume fraction of aggregated asphaltenes, ⁇ agg , as a function of the volume fraction of mixing, ⁇ m , for Souedie/Forties crude oil mixtures, as obtained from the difference between the measured I L and the hard sphere prediction for I L in FIG. 3, as described by Equation (3) later in the specification.
  • FIG. 8 shows the characteristic length scale of compact structures within asphaltene aggregates, R, as a function of the volume fraction of mixing, ⁇ m , for Souedie/Forties crude oil mixtures, as calculated using Equation (4) from I surf and ⁇ agg shown in FIGS. 5 and 7, respectively.
  • the values have been determined using Equation (1) to fit the temperature-dependent I(q) for the different mixing volume fractions, and these values are nearly identical to the measured I(q 1 ) at each ⁇ m and T.
  • the present invention includes mild heating to disaggregate asphaltenes in blended petroleum oil mixtures.
  • the presence of asphaltenes is determined by irradiating the mixture with neutrons and measuring small angle neutron scattering.
  • the preferred embodiment of the present invention includes sensitive neutron scattering for measuring the presence and quantity of asphaltene aggregates in a petroleum oil or in mixtures of two or more petroleum oils, any component of which may be an unprocessed crude oil or a processed oil derived from petroleum. Since the presence of such aggregates has been linked to fouling and coking in refineries (see U.S. Pat. Nos. 5,997,723 and 5,871,634), an objective measure of the presence of aggregates which may have submicron structures that cannot be detected using ordinary optical microscopy is desirable. By contrast, it is shown that small angle neutron scattering (SANS) is sensitive to asphaltene structures in petroleum mixtures ranging from nanometers to microns in size. In distinction to prior neutron scattering studies of asphaltenes, no contrast enhancing deuteration of any of the components in the mixture is required.
  • SANS small angle neutron scattering
  • the scattering results from inhomogeneities in the neutron scattering length density, which is related to the scattering cross sections and proximity of the various nuclei, in the test material.
  • I ( q ) I incoh +IL /(1 +q 2 ⁇ 2 )+ I surf ( q/q 1 ) ⁇ , (1)
  • I incoh is the constant high-q incoherent scattered neutron intensity
  • I L is the low-q plateau intensity of the Lorentzian
  • ⁇ is the correlation length (proportional to the radius of gyration of an asphaltene particle)
  • I surf is the low-q value of the intensity due to surface scattering from asphaltene aggregates
  • ⁇ is the absolute value of the logarithmic slope of I(q) at low q
  • q 1 is fixed by the lowest q probed in the experiment.
  • the constant incoherent scattering term is correlated to the atomic hydrogen to carbon ratio of all the free molecules in the oil.
  • the second Lorentzian term is related to the scattering from unaggregated nanometer-sized asphaltene particles.
  • the third power law term is due to surface scattering from much larger asphaltene aggregates that have been formed at an earlier time due to the aggregation of a subset of asphaltene particles after the petroleum oils have been mixed together.
  • the fits to the measured I(q) using Equation (1) are shown by the solid lines in FIGS. 1 and 2. The quality of the fits is excellent.
  • I HS ( ⁇ m ) I u ⁇ ⁇ m ⁇ ⁇ u [ 1 + 8 ⁇ a ⁇ ⁇ ⁇ m ⁇ ⁇ u + 2 ⁇ a ⁇ ( ⁇ m ⁇ ⁇ u ) 2 + 6 ⁇ b ⁇ ⁇ ⁇ m ⁇ ⁇ u ] , ( 2 )
  • Equation (2) provides a good fit to I L ( ⁇ m ) over the entire range 0 ⁇ m ⁇ 1, and the concavity is clearly a downward or negative concavity, as shown in FIG. 4.
  • Different systematic trends in the behavior of the correlation length associated with the particles as a function of ⁇ m can also be used to distinguish between compatible and incompatible mixtures and determine the range of incompatibility.
  • the incompatibility of the mixtures can also be detected more directly through the surface scattering intensity, I surf , and the power law exponent, ⁇ , that arise from the change in the neutron scattering length density at the asphaltene aggregates' surfaces.
  • I surf surface scattering intensity
  • ⁇ power law exponent
  • This criterion for determining aggregation from I surf compared to I L +I incoh can be applied to a single SANS I(q) measurement at a particular ⁇ m without the need for an entire set of measurements as a function of ⁇ m .
  • the value of the power law exponent, a can be used to determine the boundary of incompatibility; ⁇ >3 defines the existence of aggregates with surface structures that are at least fractal in nature, as shown in FIG. 6 for the Souedie/Forties crude oil mixture.
  • the boundary for incompatibility using this criterion for a yields a value for the limit of incompatibility of ⁇ m ⁇ 0.52 that is in agreement with the other criteria.
  • ⁇ agg ( ⁇ m ) ⁇ u ⁇ m [I HS ( ⁇ m ) ⁇ IL ( ⁇ m )]/ I HS ( ⁇ m ) (3)
  • the results of this calculation for the Souedie/Forties are shown in FIG. 7 and indicate that the maximum volume fraction of aggregates occurs near the center of the incompatible region around ⁇ m ⁇ 0.3.
  • the average length scale, R, of the internal structures of the aggregates can be estimated using the total surface area of the aggregates per unit volume of the oil, S V , that can be obtained from I surf : R ⁇ 3 ⁇ agg /S V , using the approximation that the internal structures are interconnected spheres of radius R.
  • the aggregated asphaltenes found in incompatible petroleum oil mixtures may be disaggregated through mild heating before introducing such mixtures into the extremely hot environment of refinery furnaces in order to inhibit the deposition and coking of carbonaceous material on the walls of the furnaces.
  • the mild preheating may be accomplished in several ways: blending the crude oils together in-line at an elevated temperature or taking a petroleum oil or petroleum oil mixture that contains asphaltene aggregates and mildly heating it in a tank for up to several hours before introducing the petroleum oil into the very hot refinery furnace.
  • asphaltenes comprise a set of molecules having highly varied atomic contents, structures, and molecular weights
  • the mild preheating may be effective enough to cause substantial, if not total, disaggregation of the asphaltene aggregates, depending upon the temperature and the time that the petroleum oil or oil mixture has been held at that temperature. Even a partial disaggregation of the asphaltenes by mild heating could be useful since the rate, of fouling of process equipment is linked to the quantity of aggregated (i.e. unsuspended) asphaltenes in the stream.
  • the solid lines in FIG. 9 are fits to the data using Equation (1).
  • the heating causes a systematic reduction in the Lorentzian plateau value, I L , for a set of Souedie/Forties crude oil mixtures having different ⁇ m in the incompatible region, as shown in FIG. 10, and it also causes a more dramatic reduction in I surf and S V as shown in FIGS. 11 and 12, respectively.
  • Suitable time/temperature ranges for the heating step include 1 minute to four weeks at a temperature between 40 and 150° C., or a preferred range of 2 minutes to 24 hours at a temperature between 40 and 100° C., a more preferred range of 3 minutes to 3 hours at a temperature between 40 and 80° C., a most preferred range of 4 minutes to 1 hour at a temperature between 40 and 60° C.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Pathology (AREA)
  • Engineering & Computer Science (AREA)
  • Analytical Chemistry (AREA)
  • Biochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Immunology (AREA)
  • Physics & Mathematics (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Food Science & Technology (AREA)
  • Medicinal Chemistry (AREA)
  • Analysing Materials By The Use Of Radiation (AREA)
  • Production Of Liquid Hydrocarbon Mixture For Refining Petroleum (AREA)
  • Working-Up Tar And Pitch (AREA)
US09/818,435 2001-03-27 2001-03-27 Disaggregation of asphaltenes in incompatible petroleum oil mixtures Abandoned US20020157991A1 (en)

Priority Applications (9)

Application Number Priority Date Filing Date Title
US09/818,435 US20020157991A1 (en) 2001-03-27 2001-03-27 Disaggregation of asphaltenes in incompatible petroleum oil mixtures
JP2002576157A JP2004532302A (ja) 2001-03-27 2002-02-15 非相溶性石油混合物中のアスファルテンの解砕
CA002439304A CA2439304A1 (en) 2001-03-27 2002-02-15 Disaggregation of asphaltenes in incompatible petroleum oil mixtures
MXPA03007847A MXPA03007847A (es) 2001-03-27 2002-02-15 Desagregacion de asfaltenos en mezclas de aceite de petroleo incompatibles.
EP02707839A EP1401768A4 (en) 2001-03-27 2002-02-15 DISCHARGING OF ASPHALTES IN INCOMPATIBLE OIL MIXTURES
PCT/US2002/005231 WO2002076889A1 (en) 2001-03-27 2002-02-15 Disaggregation of asphaltenes in incompatible petroleum oil mixtures
TW091103327A TWI238188B (en) 2001-03-27 2002-02-25 Disaggregation of asphaltenes in incompatible petroleum oil mixtures
ARP020100695A AR032874A1 (es) 2001-03-27 2002-02-27 Desagregacion de asfaltenos en mezclas incompatibles de aceites de petroleo
US10/699,232 US7029570B2 (en) 2001-03-27 2003-10-31 Disaggregation of asphaltenes in incompatible petroleum oil mixtures

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US09/818,435 US20020157991A1 (en) 2001-03-27 2001-03-27 Disaggregation of asphaltenes in incompatible petroleum oil mixtures

Related Child Applications (1)

Application Number Title Priority Date Filing Date
US10/699,232 Continuation US7029570B2 (en) 2001-03-27 2003-10-31 Disaggregation of asphaltenes in incompatible petroleum oil mixtures

Publications (1)

Publication Number Publication Date
US20020157991A1 true US20020157991A1 (en) 2002-10-31

Family

ID=25225530

Family Applications (2)

Application Number Title Priority Date Filing Date
US09/818,435 Abandoned US20020157991A1 (en) 2001-03-27 2001-03-27 Disaggregation of asphaltenes in incompatible petroleum oil mixtures
US10/699,232 Expired - Fee Related US7029570B2 (en) 2001-03-27 2003-10-31 Disaggregation of asphaltenes in incompatible petroleum oil mixtures

Family Applications After (1)

Application Number Title Priority Date Filing Date
US10/699,232 Expired - Fee Related US7029570B2 (en) 2001-03-27 2003-10-31 Disaggregation of asphaltenes in incompatible petroleum oil mixtures

Country Status (8)

Country Link
US (2) US20020157991A1 (zh)
EP (1) EP1401768A4 (zh)
JP (1) JP2004532302A (zh)
AR (1) AR032874A1 (zh)
CA (1) CA2439304A1 (zh)
MX (1) MXPA03007847A (zh)
TW (1) TWI238188B (zh)
WO (1) WO2002076889A1 (zh)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20080149486A1 (en) * 2006-12-20 2008-06-26 Exxonmobil Research And Engineering Company Focused beam reflectance measurement to optimize desalter performance and reduce downstream fouling
US9038451B2 (en) 2010-07-08 2015-05-26 Baker Hughes Incorporated Optical method for determining fouling of crude and heavy fuels

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
MX357637B (es) * 2007-11-28 2018-07-16 Saudi Arabian Oil Company Star Proceso para reducir la acidez del petróleo crudo.
EP2467450B1 (en) 2009-08-17 2016-05-04 Brack Capital Energy Technologies Limited Oil sands extraction
KR101287300B1 (ko) 2012-04-17 2013-07-17 에스케이에너지 주식회사 안정화된 탄화수소 오일 블렌드의 제조방법
US9791359B2 (en) 2013-12-06 2017-10-17 Instituto Mexican Del Petroleo Process for determining the incompatibility of mixtures containing heavy and light crudes
JP5717159B1 (ja) * 2014-10-04 2015-05-13 秀樹 相澤 溶液散乱法の放射線強度から散乱断面積に変換する方法
JP7751169B2 (ja) * 2021-05-12 2025-10-08 国立大学法人茨城大学 中性子イメージング装置、及び中性子イメージング方法

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3136711A (en) * 1961-03-27 1964-06-09 Exxon Research Engineering Co Process for reducing the pour points of crude oils
US4514283A (en) * 1984-01-26 1985-04-30 Shell Oil Company Process for separating and converting heavy oil asphaltenes in a field location
US5207891A (en) * 1991-12-30 1993-05-04 Texaco Inc. Composition of matter for oligomeric aliphatic ether asphaltenes as asphaltene dispersants
US5843303A (en) * 1997-09-08 1998-12-01 The M. W. Kellogg Company Direct fired convection heating in residuum oil solvent extraction process
US5969237A (en) * 1997-10-09 1999-10-19 Baker Hughes Incorporated Measurement and control of asphaltene agglomeration in hydrocarbon Liquids

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20080149486A1 (en) * 2006-12-20 2008-06-26 Exxonmobil Research And Engineering Company Focused beam reflectance measurement to optimize desalter performance and reduce downstream fouling
US20100038286A1 (en) * 2006-12-20 2010-02-18 Greaney Mark A Focused beam reflectance measurement to optimized desalter performance and reduce downstream fouling
US7927479B2 (en) * 2006-12-20 2011-04-19 Exxonmobil Research And Engineering Company Focused beam reflectance measurement to optimize desalter performance and reduce downstream fouling
US9038451B2 (en) 2010-07-08 2015-05-26 Baker Hughes Incorporated Optical method for determining fouling of crude and heavy fuels

Also Published As

Publication number Publication date
US7029570B2 (en) 2006-04-18
MXPA03007847A (es) 2004-04-02
AR032874A1 (es) 2003-11-26
EP1401768A1 (en) 2004-03-31
EP1401768A4 (en) 2007-01-03
JP2004532302A (ja) 2004-10-21
CA2439304A1 (en) 2002-10-03
WO2002076889A1 (en) 2002-10-03
US20040089589A1 (en) 2004-05-13
TWI238188B (en) 2005-08-21

Similar Documents

Publication Publication Date Title
Maranzano et al. The effects of interparticle interactions and particle size on reversible shear thickening: Hard-sphere colloidal dispersions
Soleymanzadeh et al. A review on methods of determining onset of asphaltene precipitation
Radliński et al. Small angle neutron scattering signature of oil generation in artificially and naturally matured hydrocarbon source rocks
Maranzano et al. The effects of particle size on reversible shear thickening of concentrated colloidal dispersions
Degiorgio et al. Static and dynamic light scattering study of fluorinated polymer colloids with a crystalline internal structure
Suresh et al. Direct measurement of the effect of surface roughness on the colloidal forces between a particle and flat plate
Yudin et al. Dynamic light scattering monitoring of asphaltene aggregation in crude oils and hydrocarbon solutions
Charalampopoulos et al. Agglomerate parameters and fractal dimension of soot using light scattering—effects on surface growth
Barré et al. Relation between nanoscale structure of asphaltene aggregates and their macroscopic solution properties
US7029570B2 (en) Disaggregation of asphaltenes in incompatible petroleum oil mixtures
Hosoda et al. Measurement of anisotropic Brownian motion near an interface by evanescent light-scattering spectroscopy
WO2019126181A1 (en) Testing the effect of solvating agents on the stability of asphaltene dispersions
Derakhshesh et al. Dispersion of asphaltene nanoaggregates and the role of Rayleigh scattering in the absorption of visible electromagnetic radiation by these nanoaggregates
Ahmed et al. An integrated review on asphaltene: definition, chemical composition, properties, and methods for determining onset precipitation
US6690453B2 (en) Method and device for predicting the flocculation threshold of asphaltenes contained in hydrocarbon mixtures
Yoshida et al. Particle size measurement with an improved sedimentation balance method and microscopic method together with computer simulation of necessary sample size
Shojaei et al. Kinetic modeling of asphaltene nano-aggregates formation using dynamic light scattering technique
Burya et al. Colloidal properties of crude oils studied by dynamic light-scattering
AU2002242216A1 (en) Disaggregation of ashaltenes in incompatible petroleum oil mixtures
Kuryakov et al. Study of phase transitions in n-tricosane/bitumen aqueous dispersions by the optical method
Sheu Self-association of asphaltenes: structure and molecular packing
Walz et al. The effect of nanoscale roughness on long range interaction forces
Van der Veen et al. Structural ordering at the solid–liquid interface
Celis et al. Continuous spectroscopy characterization of emulsions
Bradbury et al. Deformation, melting, and relaxation of structured colloidal dispersions

Legal Events

Date Code Title Description
AS Assignment

Owner name: EXXONMOBIL RESEARCH & ENGINEERING CO., NEW JERSEY

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:MASON, THOMAS G.;LIN, MIN YUE;REEL/FRAME:011581/0257

Effective date: 20010321

STCB Information on status: application discontinuation

Free format text: ABANDONED -- FAILURE TO PAY ISSUE FEE