WO2007112967A1 - Process for the preparation of water-in-oil and oil-in-water nanoemulsions - Google Patents

Process for the preparation of water-in-oil and oil-in-water nanoemulsions Download PDF

Info

Publication number
WO2007112967A1
WO2007112967A1 PCT/EP2007/002863 EP2007002863W WO2007112967A1 WO 2007112967 A1 WO2007112967 A1 WO 2007112967A1 EP 2007002863 W EP2007002863 W EP 2007002863W WO 2007112967 A1 WO2007112967 A1 WO 2007112967A1
Authority
WO
WIPO (PCT)
Prior art keywords
water
oil
active agents
hlb
process according
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.)
Ceased
Application number
PCT/EP2007/002863
Other languages
French (fr)
Other versions
WO2007112967A8 (en
Inventor
Lucilla Del Gaudio
Thomas Paul Lockhart
Alessandra Belloni
Rossella Bortolo
Roberto Tassinari
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.)
Eni SpA
Versalis SpA
Original Assignee
Eni SpA
Polimeri Europa SpA
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 Eni SpA, Polimeri Europa SpA filed Critical Eni SpA
Priority to CN200780016432XA priority Critical patent/CN101443436B/en
Priority to EP07723805.3A priority patent/EP2001981B1/en
Priority to US12/294,552 priority patent/US8431620B2/en
Priority to ES07723805T priority patent/ES2781798T3/en
Priority to JP2009501962A priority patent/JP5694659B2/en
Priority to CA2646175A priority patent/CA2646175C/en
Priority to KR1020087026798A priority patent/KR101411754B1/en
Publication of WO2007112967A1 publication Critical patent/WO2007112967A1/en
Priority to IL194255A priority patent/IL194255A/en
Anticipated expiration legal-status Critical
Priority to NO20084312A priority patent/NO345201B1/en
Publication of WO2007112967A8 publication Critical patent/WO2007112967A8/en
Priority to US13/845,515 priority patent/US9884299B2/en
Priority to CY20201100328T priority patent/CY1124094T1/en
Ceased legal-status Critical Current

Links

Classifications

    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K8/00—Cosmetics or similar toiletry preparations
    • A61K8/02—Cosmetics or similar toiletry preparations characterised by special physical form
    • A61K8/04—Dispersions; Emulsions
    • A61K8/06—Emulsions
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K8/00—Cosmetics or similar toiletry preparations
    • A61K8/18—Cosmetics or similar toiletry preparations characterised by the composition
    • A61K8/30—Cosmetics or similar toiletry preparations characterised by the composition containing organic compounds
    • A61K8/49—Cosmetics or similar toiletry preparations characterised by the composition containing organic compounds containing heterocyclic compounds
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K9/00—Medicinal preparations characterised by special physical form
    • A61K9/10—Dispersions; Emulsions
    • A61K9/107—Emulsions ; Emulsion preconcentrates; Micelles
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K9/00—Medicinal preparations characterised by special physical form
    • A61K9/10—Dispersions; Emulsions
    • A61K9/107—Emulsions ; Emulsion preconcentrates; Micelles
    • A61K9/1075—Microemulsions or submicron emulsions; Preconcentrates or solids thereof; Micelles, e.g. made of phospholipids or block copolymers
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
    • B01F23/00—Mixing according to the phases to be mixed, e.g. dispersing or emulsifying
    • B01F23/40—Mixing liquids with liquids; Emulsifying
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
    • B01F23/00—Mixing according to the phases to be mixed, e.g. dispersing or emulsifying
    • B01F23/40—Mixing liquids with liquids; Emulsifying
    • B01F23/41—Emulsifying
    • B01F23/4105—Methods of emulsifying
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
    • B01F23/00—Mixing according to the phases to be mixed, e.g. dispersing or emulsifying
    • B01F23/40—Mixing liquids with liquids; Emulsifying
    • B01F23/41—Emulsifying
    • B01F23/414—Emulsifying characterised by the internal structure of the emulsion
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K23/00—Use of substances as emulsifying, wetting, dispersing, or foam-producing agents
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K23/00—Use of substances as emulsifying, wetting, dispersing, or foam-producing agents
    • C09K23/017—Mixtures of compounds
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K8/00—Compositions for drilling of boreholes or wells; Compositions for treating boreholes or wells, e.g. for completion or for remedial operations
    • C09K8/52—Compositions for preventing, limiting or eliminating depositions, e.g. for cleaning
    • C09K8/524—Compositions for preventing, limiting or eliminating depositions, e.g. for cleaning organic depositions, e.g. paraffins or asphaltenes
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K8/00—Compositions for drilling of boreholes or wells; Compositions for treating boreholes or wells, e.g. for completion or for remedial operations
    • C09K8/52—Compositions for preventing, limiting or eliminating depositions, e.g. for cleaning
    • C09K8/528—Compositions for preventing, limiting or eliminating depositions, e.g. for cleaning inorganic depositions, e.g. sulfates or carbonates
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K8/00—Compositions for drilling of boreholes or wells; Compositions for treating boreholes or wells, e.g. for completion or for remedial operations
    • C09K8/52—Compositions for preventing, limiting or eliminating depositions, e.g. for cleaning
    • C09K8/536—Compositions for preventing, limiting or eliminating depositions, e.g. for cleaning characterised by their form or by the form of their components, e.g. encapsulated material
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K8/00—Compositions for drilling of boreholes or wells; Compositions for treating boreholes or wells, e.g. for completion or for remedial operations
    • C09K8/54—Compositions for in situ inhibition of corrosion in boreholes or wells
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G OR C10K; LIQUIFIED PETROLEUM GAS; USE OF ADDITIVES TO FUELS OR FIRES; FIRE-LIGHTERS
    • C10L1/00—Liquid carbonaceous fuels
    • C10L1/32—Liquid carbonaceous fuels consisting of coal-oil suspensions or aqueous emulsions or oil emulsions
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G OR C10K; LIQUIFIED PETROLEUM GAS; USE OF ADDITIVES TO FUELS OR FIRES; FIRE-LIGHTERS
    • C10L1/00—Liquid carbonaceous fuels
    • C10L1/32—Liquid carbonaceous fuels consisting of coal-oil suspensions or aqueous emulsions or oil emulsions
    • C10L1/328—Oil emulsions containing water or any other hydrophilic phase
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
    • B01F23/00—Mixing according to the phases to be mixed, e.g. dispersing or emulsifying
    • B01F23/40—Mixing liquids with liquids; Emulsifying
    • B01F23/41—Emulsifying
    • B01F23/414—Emulsifying characterised by the internal structure of the emulsion
    • B01F23/4142—Inversed-type emulsions

Definitions

  • the present invention relates to a process for the preparation of water-in-oil and oil-in-water nanoemulsions . More specifically, the invention relates to a low energy process which allows stable nanoemulsions to be obtained by varying the hydrophilic and lipophilic balance (HLB) of the surface-active agents present in the system.
  • HLB hydrophilic and lipophilic balance
  • the nanoemulsion technology i.e. emulsions whose dimensions are smaller than 500 nm, is a growing technology which transversely affects many industrial areas.
  • nanoemulsions are mainly used today in high value added fields, such as the cosmetic and pharmaceutical field.
  • nanoemulsions are used for carrying active principles soluble in water into an oil compatible with the skin, in order to bring the ac- tive principles directly into the tissues, thus reducing the amount of active principle used.
  • nanoemulsions have proved to be effective for spreading anti-bacterial or anti- fungus agents, viruses which are directly transported into the cells by the fusion of the nanoemulsion with the cell membrane.
  • nanoemulsions for eradicating viruses such as anthrax and AIDS are under study, and also as a carrier of antitumour agents.
  • nanoemulsions could carry products, not transportable with oil due to their non-solubility, to areas in which large amounts of water cannot be conveyed, due to problems relating to corrosion, damage etc...
  • nanoemulsions could be used as carriers of scale inhibitors, corrosion inhibitors or wax and as- phaltene inhibitors, or for acidic treatment of the formation. They can also be used for cleaning oil pipelines.
  • nanoemulsions also suffer from the lack of scientific criteria for their formulation.
  • the highest critical point for the formation of nanoemulsions with respect to the corresponding macroemulsions lies in the higher energy necessary for obtaining them, due to the very small dimensions of the droplets of the dispersed phase (smaller than 500 nm) .
  • phase inversion Phase Inversion Temperature
  • oil-in-water nanoemulsions have been obtained by means of phase inversion [Patrick Fernandez, Valeris Andre, Jens Rieger, Angelika Kuhnle, Colloids and Surfaces A: Physicochem. Eng. Aspects 251 (2004) 53-58] by varying the water/oil ratio (catastrophic inversion, the nanoemulsions obtained are between 100 and 500 nm) or by the dilution of microemulsions [R. Pons, I. Carrera, J. Caelles, J. Rouch, P. Panizza, Advances in Colloid and Interface Science, 106, (2003) 129-146] .
  • Italian patent application nr. MI 03A002101 describes a three-step low energy process for the preparation of water-in-diesel nanoemulsions, comprising the preparation of a blend of surface-active agents so as to obtain a first emulsion, transformation of the first emulsion into a second birefringent emulsion, mixing of the birefringent emulsion with diesel in order to obtain the desired nanoemulsion.
  • the water- in-gas oil nanoemulsions obtained through this method are practically mono-dispersed, as they comprise a reduced quantities of a composition of non- ionic surface-active agents (1 to 5% by weight; much lower than that of microemulsions) and are characterized by a high stability.
  • a low energy process has now been found for the prepa- ration of mono-dispersed water-in-oil and oil-in-water nanoemulsions, with a high stability, having the characteristic of being simpler and with a wider applicability range with respect to those described in the known art.
  • the process of the invention also allows the preparation of nanoemulsions with a high formation kinetics, so that they are obtained within a few hours after their dilution, whereas the method described in patent application nr. MI 03A002101 requires longer times (a few days) for their formation.
  • the process of the invention is based on the capacity of a system based on water and oil, of inverting the phase by varying the hydrophilie/lipophilic balancing of the surface active agents present in the system (HLB) .
  • the inversion takes place by the dilution of a homogeneous blend (concentrated precursor) characterized by a certain HLB and an interface tension lower than 1 mN/m, in a dispersing phase (oil or water) which contains a surface- active agent capable of conferring a different HLB to the final dispersion with respect to the precursor.
  • the HLB of the nanoemulsion is lower than that of the precursor in the case of water-in-oil dispersions, whereas it is higher than that of the precursor, in the case of oil-in-water dispersions.
  • an instantaneous phase inversion occurs, together with the formation of the nanoemulsion.
  • a process for the preparation of a water-in-oil or oil-in-water nanoemulsion in which the dispersed phase is distributed in the dispersing phase, in the form of droplets having a diameter ranging from 1 to 500 ran represents a first object of the present invention, which comprises:
  • a homogeneous water/oil blend (1) characterized by an interface tension lower than 1 mN/m, comprising water in a quantity of 30 to 70% by weight, at least two surface-active agents having a different HLB, selected from non-ionic, anionic, polymeric surface-active agents, the latter being present in such a quantity as to make the blend homogeneous;
  • the HLB of the final nanoemulsion is selected on the basis of that of the corresponding micro-emulsion charac- terized by the same water/oil ratio as the nanoemulsion, but with a total quantity of surface-active agents such as to make the blend homogeneous by the simple addition of all the components.
  • an amount of dispersing phase and surface-active agent is used in order to obtain a nanoemulsion having a HLB higher than that of the blend (1) .
  • Nano-emulsions are obtained only by operating in accordance with the process of the invention: the preparation of a blend having the same final composition, but without following the procedure specified (preparation of the precursor, order of addition of the reagents, etc..) does not produce a limpid nanoemulsion, but an opaque and milky macro-emulsion characterized by droplets having dimensions well above a micron.
  • Homogeneous blends can be advantageously prepared, comprising from 5 to 50% by weight of surface-active agents and in which the weight ratio of the surface-active agents used gives a HLB value higher than 8, preferably between 10 and 15 for non- ionic, and over 20 for anionic surface- active agents .
  • the concentration of surface-active agents in the blend is in relation to the final water/oil amount which is to be dispersed.
  • the weight proportion between the concentration of the surface-active agents in the blend and the amount of water/oil to be dispersed can vary from 0.07 to 3.5, preferably from 0.1 to 2.
  • the surface-active agents used for the preparation of the blend can be selected from non- ionic, anionic, poly- meric surface-active agents, preferably non- ionic and polymeric surface-active agents.
  • Blends can be suitably prepared comprising a first surface-active agent selected from non-ionic lipophilic surface-active agents (A type) , a second surface-active agent selected from non-ionic hydrophilic surface-active agents (B type) , a third surface-active agent selected from polymeric surface-active agents (C type) , the composition of surface-active agents (A) + (B) + (C) having a HLB ranging from 8 to 16, preferably from 10 to 15.
  • Preferred formulations include a lipophilic non- ionic surface-active agent of the fatty acid ester group having a HLB higher than 11 and a non- ionic, polymeric surface-active agent with a HLB varying from 4 to 14.
  • the mix has the appearance of a limpid to translucent solution and is characterized by a high stability as it al- lows nanoemulsions to be prepared by dilution even up to a year after its preparation.
  • the blend maintains its properties even after being subjected to freezing.
  • the preparation can be effected at a temperature rang- ing from 5 to 60 0 C.
  • the mixture of surface- active agents selected from non-ionic, anionic and polymeric surface-active agents, is dissolved in oil so as to obtain the desired HLB, and when the dissolution is complete, the water solution is added under stirring.
  • the aqueous solution can be deionised water or water with additives. At the end of the addition, the blend will appear homogeneous and limpid. This precursor blend can be used for preparing water-in-oil and oil-in-water nanoemulsions .
  • the precursor mix is added, at room temperature, slowly, and under stirring to a solution consisting of oil and the lipophilic surface-active agent selected from non- ionic and polymeric surface-active agents.
  • the precursor mix is added, at room temperature, slowly, and under stirring to a solution consisting of an aqueous solu- tion and the hydrophilic surface-active agent selected from non- ionic and polymeric surface-active agents.
  • the nanoemulsion preparation is effected at a temperature ranging from 5 to 60 0 C.
  • the nanoemulsions obtained through the process of the invention can be formulated with a different content of dispersed water or oil, they are stable for over 6 months, do not require particular care for their preservation, and maintain their characteristics up to a temperature of 70 0 C.
  • nanoemulsions having a wider concentration range of dispersed phase by means of a sole formulation of a homogeneous blend (or precursor) .
  • the dilution is effected using an amount of dispersing phase and surface-active agent such as to obtain a nanoemulsion having a HLB at least 0.5 units lower with respect to that of the homogeneous blend (1) .
  • the surface-active agent which is dissolved in the oily phase, is selected from non- ionic lipophilic surface-active agents, preferably non- ionic surface-active agents of the group of esters of fatty acids, and the homo- geneous blend is prepared with non- ionic and polymeric sur- face-active agents, the nanoemulsion must have a HLB 0.8 - 5 units lower.
  • the dilution is effected with a quantity of dispersing phase and surface-active agent such as to obtain a nanoemulsion having a HLB at least 0.5 units higher with respect to that of the homogeneous blend (1) .
  • the surface-active agent which is dissolved in the aqueous phase is selected from non-ionic hydrophilic surface-active agents, preferably from non- ionic surface-active agents of the group of alkyl glucosides and the homogeneous blend is prepared with non- ionic and polymeric surface-active agents, the nanoemulsion should have a HLB 0.8 -5 units higher.
  • Water-in-oil nanoemulsions can be prepared by operating according to the procedure of the invention, having a HLB value ranging from 6 to 14, comprising a water content ranging from 1 to 30%, and a total amount of surface-active agents ranging from 0.1 to 20%, the complement to a hundred being oil.
  • Water- in-oil nanoemulsions can preferably be prepared with a HLB value ranging from 9 to 13, comprising a water content ranging from 5 to 25% and total surface-active agents ranging from 1.5 to 12%, the complement to a hundred being oil.
  • Oil-in-water nanoemulsions can also be conveniently prepared having a HLB value higher than 10, comprising an oil content ranging from 1% to 30% and total surface-active agents from 0.1 to 20%, the complement to a hundred being oil.
  • Oil-in-water nanoemulsions can be preferably prepared with a HLB value ranging from 11 to 16, comprising an oil content ranging from 5 to 25% and total surface-active agents from 1.5 to 12%, the complement to a hundred being water. Any polar or apolar oil, preferably insoluble in water, can be used for the purposes of the present invention.
  • the oil is preferably selected from the group of linear or branched hydrocarbons, such as, for example, dodecane, or complex mixtures of hydrocarbons such as gas oil, kero- sene, soltrol, mineral spirits.
  • any additive can be englobed in the nano- emulsions and they can be used in the food, oil, cosmetic, pharmaceutical and fuel industries, where they are used as additive carriers.
  • nanoemulsions of the present inven- tion can be suitably used in the oil industry, for the injection of additives into the well, which cannot be carried with the oil (as they are not soluble) or for the injection of acid solutions in areas which cannot be reached by large amounts of water due to problems relating to corrosion, damage, etc..
  • the nanoemulsions of the invention can also be formulated so as to contemporaneously carry two different additives, incompatible with each other, such as, for example, a scale inhibitor in aqueous phase (dispersed phase) and a wax/asphaltene inhibitor in organic phase (the two additives are incompatible as they are soluble in different solvents) , or a scale inhibitor in aqueous phase and a corrosion inhibitor in organic phase (the two additives are chemically incompatible) .
  • two different additives incompatible with each other
  • two different additives incompatible with each other
  • two different additives incompatible with each other
  • two different additives incompatible with each other
  • two different additives incompatible with each other
  • two different additives incompatible with each other
  • two different additives incompatible with each other
  • two different additives incompatible with each other
  • two different additives incompatible with each other
  • two different additives incompatible with each other
  • two different additives incompatible with each other
  • a scale inhibitor in aqueous phase dis
  • the nanoemulsions When used upstream, the nanoemulsions must not damage the formation and, under suitable conditions, release the dispersed phase containing the additives .
  • the nanoemulsions can also be formulated using aqueous solutions as dispersed phase.
  • aqueous solutions can consist of salt solutions, such as, for example, chlorides, bromides, sulphates, phosphates of alkaline metals (sodium, potassium) , alkaline-earth metals (calcium) or transition metals (silver, cobalt, nickel, copper, zinc, iron) .
  • the aqueous solutions can also consist of hydro-soluble additive solutions, such as, for example, urea, oxygenated water, scale inhibitors (such as, for example, phosphono- carboxylic acids, amino phosphonic acids, organic sulphates, etc.. ) .
  • the aqueous solutions can contain from 0.1 to 50% by weight of additive and preferably from 5 to 20%.
  • Nanoemulsions containing water with additives are normally prepared by diluting a precursor already containing the desired additive solution in the oily dispersing phase containing the lipophilic surface-active agent.
  • Example 1 Formulation of the precursor.
  • the precursor suitable for the formulation of water-in- oil nanoemulsions in which the oil is dodecane and the dispersed phase is deionised water, can be formulated ac- cording to the following procedure.
  • Atlox 4914 (Uniqema) , 1.563 gr of Span 80 (Fluka) and 3.588 gr. of Glucopone 600 CS UP (Fluka, 50% water solution) are weighed in a single container and dissolved in 8.233 gr. of dodecane. When the dissolution is complete, 6.439 gr. of deionised water are added under vigorous stirring by means of a magnetic stirrer. The precursor is characterized by a HLB value of 10.8 and is indefinitely stable.
  • Example 2 Formulation of nanoemulsions with 6.8% of water as dispersed phase.
  • Span 80 0.073 gr of Span 80 are dissolved in 8.275 gr of dodecane in order to obtain 10 gr of nanoemulsion.
  • 1.652 gr of precursor, as prepared in example 1 are slowly added under stirring (magnetic stirrer) to this solution.
  • the nanoemulsion thus formulated has droplets of dispersed phase around 30 - 40 nm, a polydispersity index lower than 0.1 and it is stable for over a year.
  • Example 3
  • Span 80 0.096 gr of Span 80 are dissolved in 7.475 gr of dode- cane in order to obtain 10 gr of nanoemulsion.
  • 2.429 gr of precursor, as prepared in example 1 are slowly added under stirring (magnetic stirrer) to this solution.
  • the nanoemulsion thus formulated has droplets of dispersed phase around 30 - 50 nm, a polydispersity index lower than 0.15 and is stable for over a year.
  • Span 80 0.131 gr of Span 80 are dissolved in 5.010 gr of dode- cane in order to obtain 10 gr of nanoemulsion.
  • 4.858 gr of precursor, as prepared in example 1 are slowly added under stirring (magnetic stirrer) to this solution.
  • the nanoemulsion thus formulated has droplets of dis- persed phase around 40 - 60 nm, a polydispersity index lower than 0.2 and it is stable for over six months .
  • the precursor suitable for the formulation of water- in- oil nanoemulsions in which the oil is dodecane and the dispersed phase is an aqueous solution containing 5% by weight of a scale inhibitor, can be formulated according to the following procedure.
  • the precursor suitable for the formulation of water-in- oil nanoemulsions in which the oil is dodecane and the dispersed phase is an aqueous solution containing 10% by weight of an scale inhibitor, can be formulated according to the following procedure.
  • the precursor suitable for the formulation of water- in- oil nanoemulsions, in which the oil is dodecane and the dispersed phase is an aqueous solution containing 15% by- weight of a scale inhibitor can be formulated according to the following procedure. 0.151 gr of Atlox 4914 (Unigema) , 0.869 gr of Span 80 (Fluka) and 3.985 gr of Glucopone 600 CS UP (Fluka, 50% solution in water) are weighed in a single container and are dissolved in 7.519 gr of dodecane.
  • Span 80 0.081 gr. of Span 80 are dissolved in 3.094 gr of dodecane, in order to obtain 10 gr of nanoemulsion. 2.826 gr of precursor, as prepared in example 5, are added to this solution, slowly and under stirring (magnetic stirrer) .
  • the nanoemulsion thus formulated has droplets of dis- persed phase around 40 - 60 nm, a polydispersity index lower than 0.2 and it is stable for over six months.
  • Example 9
  • the nanoemulsion thus formulated has droplets of dispersed phase around 40 - 60 nm, a polydispersity index lower than 0.2 and it is stable for over six months.
  • Example 10 Formulation of nanoemulsions with the addition in aqueous phase of scale inhibitors.
  • Span 80 0.101 gr. of Span 80 are dissolved in 7.5 gr of dode- cane, in order to obtain 10 gr of nanoemulsion.
  • 2.4 gr of precursor, as prepared in example 6, are added to this so- lution, slowly and under stirring (magnetic stirrer) .
  • the nanoemulsion thus formulated has droplets of dispersed phase around 40 - 60 nm, a polydispersity index lower than 0.2 and it is stable for over six months.
  • Span 80 0.134 gr. of Span 80 are dissolved in 6.3 gr of dode- cane, in order to obtain 10 gr of nanoemulsion.
  • 3.5 gr of precursor, as prepared in example 6, are added to this solution, slowly and under stirring (magnetic stirrer) .
  • the nanoemulsion thus formulated has droplets of dispersed phase around 40 - 60 nm, a polydispersity index lower than 0.2 and it is stable for over six months.
  • Span 80 0.157 gr. of Span 80 are dissolved in 5.134 gr of dodecane, in order to obtain 10 gr of nanoemulsion. 4.709 gr of precursor, as prepared in example 6, are added to this solution, slowly and under stirring (magnetic stirrer) .
  • the nanoemulsion thus formulated has droplets of dispersed phase around 40 - 60 nm, a polydispersity index lower than 0.2 and it is stable for over six months.
  • Span 80 0.070 gr. of Span 80 are dissolved in 3.105 gr of do- decane, in order to obtain 10 gr of nanoemulsion. 2.826 gr of precursor, as prepared in example 7, are added to this solution, slowly and under stirring (magnetic stirrer) .
  • the nanoemulsion thus formulated has droplets of dis- persed phase around 40 - 60 nm, a polydispersity index lower than 0.2 and it is stable for over six months .
  • Example 14 Formulation of nanoemulsions with the addition in aqueous phase of scale inhibitors, using gas oil, or sol- trol or mineral spirits as continuous phase.
  • Nanoemulsions can be obtained by indifferently using one of the above-mentioned hydrocarbons by applying the following procedure.
  • Span 80 0.085 gr. of Span 80 are dissolved in 3.090 gr of die- sel or soltrol or mineral spirits to obtain 6 gr of nanoe- mulsion.
  • the nanoemulsion thus formulated has droplets of dispersed phase around 40 - 60 nm, a polydispersity index lower than 0.2 and it is stable for over six months .
  • Span 80 0.068 gr. of Span 80 are dissolved in 3.106 gr of kerosene to obtain 6 gr of nanoemulsion.
  • the nanoemulsion thus formulated has droplets of dis- persed phase around 40 - 60 ran, a polydispersity index lower than 0.2 and it is stable for over six months.
  • the precursor suitable for the formulation of water-in- oil nanoemulsions in which oil is a 10% solution by weight of a wax/asphaltene inhibitor (FX 1972 of Ondeo Nalco) in dodecane and the dispersed phase is an aqueous solution containing 10% by weight of a scale inhibitor, can be for- mulated according to the following procedure.
  • the nanoemulsion thus formulated has droplets of dispersed phase around 30 - 40 nm, a polydispersity index lower than 0.2 and it is stable for over six months.
  • Span 80 0.157 gr of Span 80 are dissolved in 5.134 gr of a solution containing 1300 ppm of a corrosion inhibitor (Inicor R200 of Lamberti) in dodecane in order to obtain 10 gr of nanoemulsion.
  • the nanoemulsion thus formulated has droplets of dis- persed phase around 30 - 40 nm, a polydispersity index lower than 0.2 and it is stable for over six months.
  • Example 19 Formulation of the precursor for oil-in-water nanoemul- sions .
  • the precursor suitable for the formulation of oil-in- water nanoemulsions, in which the oil is dodecane and the dispersed phase is deionised water, can be formulated ac- cording to the following procedure.
  • Example 20 Formulation of oil-in-water nanoemulsions with 6.8% of dodecane as dispersed phase.
  • Span 80 0.174 gr of Span 80 are dissolved in 4.8 gr of water. 1.0 gr of a precursor as prepared in example 19, are slowly added under stirring (magnetic stirrer) to this solution.
  • the nanoemulsion thus formulated has droplets of dispersed phase around 30 - 40 nm, a polydispersity index lower than 0.2 and it is stable for over six months .
  • the precursor blend having a HLB of 10.8 is prepared as in example 1.
  • 0.214 gr of Span 80 (Fluka) are dissolved in 4.928 gr of dodecane.
  • 4,858 gr of a precursor blend prepared as in example 1 are slowly added under stirring to the solution thus obtained.
  • a suspension is obtained characterised by a HLB of 9.6 but having an opaque and milky appearance, with the dimensions of the dispersed phase droplets higher than 500 nm.
  • Atlox 4914 Uniqema
  • Span 80 Fluka
  • Glucopone 600 CS UP Fluka, 50% water solution
  • the precursor is characterized by a HLB value of 10.2 and is separated into two phases.
  • 0.033 of Span 80 are dissolved in 5.100 gr of dodecane. 4.900 gr of a precursor mix prepared as described in this example, are slowly added, under stirring to the solu- tion thus obtained.
  • a suspension is obtained, characterised by a HLB of 10, but having an opaque and milky appearance, with the tendency of depositing into two phases.
  • the nanoemulsion remains unaltered up to a temperature of 80 0 C, when it begins to show a slight separation of the aqueous phase. At a temperature of 100 0 C, the aqueous phase is completely separated, allowing the release of the hydro- soluble additive, which follows the same destiny as the aqueous phase .
  • Example 26
  • a column having a height of 20 cm and a diameter of 1.9 cm is packed with quartzite having a particle-size greater than 230 mesh and flushed with dodecane at a tem- perature of 90 0 C.
  • the initial permeability to dodecane proves to be 55 mD, with a pore volume (PV) equal to 28.9 cm 3 .
  • the column is flushed again with dodecane until the complete separation of the nanoemulsion, and the permeability to dodecane is determined again.
  • the quartzite contained in the column is discharged and analyzed to evaluate the adsorp- tion of the inhibitor, which proves to be equal to 0.6 mg/g quartzite (4% with respect to the total) , typical of scale inhibitors of this group (REF: M. Andrei, A. Malandrino, Petrol. Sci Technol., 2003, 21(7-8)1295-1315).

Landscapes

  • Chemical & Material Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Organic Chemistry (AREA)
  • Materials Engineering (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • General Health & Medical Sciences (AREA)
  • Epidemiology (AREA)
  • Veterinary Medicine (AREA)
  • Public Health (AREA)
  • Animal Behavior & Ethology (AREA)
  • Dispersion Chemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Pharmacology & Pharmacy (AREA)
  • Medicinal Chemistry (AREA)
  • Inorganic Chemistry (AREA)
  • Molecular Biology (AREA)
  • Biophysics (AREA)
  • Birds (AREA)
  • Colloid Chemistry (AREA)
  • Medicinal Preparation (AREA)
  • Cosmetics (AREA)
  • Edible Oils And Fats (AREA)
  • Detergent Compositions (AREA)

Abstract

Process for the preparation of a water-in-oil or oil-in- water nanoemulsion wherein the dispersed phase is distributed in the dispersing phase in the form of droplets having a diameter ranging from 1 to 500 nm, comprising: 1) the preparation of a homogeneous water/oil blend (I) characterized by an interface tension lower than 1 mN/m, comprising water in an amount of 30 to 70% by weight, at least two surface-active agents having a different HLB, selected from non-ionic, anionic, polymeric surface-active agents, said surface-active agents being present in such a quantity as to make the blend homogeneous; 2) the dilution of the blend (I) in a dispersing phase consisting of oil or water with the addition of a surface- active agent, selected from non-ionic, anionic, polymeric surface-active agents, the quantity of the dispersing phase and surface-active agent being such as to obtain a nanoemulsion having a HLB different from that of the blend (I) .

Description

PROCESS FOR THE PREPARATION OF WATER-IN-OIL AND OIL-IN- WATER NANOEMULSIONS
The present invention relates to a process for the preparation of water-in-oil and oil-in-water nanoemulsions . More specifically, the invention relates to a low energy process which allows stable nanoemulsions to be obtained by varying the hydrophilic and lipophilic balance (HLB) of the surface-active agents present in the system. The nanoemulsion technology, i.e. emulsions whose dimensions are smaller than 500 nm, is a growing technology which transversely affects many industrial areas.
Due to the considerable preparation cost and limited stability during the time, however, nanoemulsions are mainly used today in high value added fields, such as the cosmetic and pharmaceutical field.
In the cosmetic field, for example, nanoemulsions are used for carrying active principles soluble in water into an oil compatible with the skin, in order to bring the ac- tive principles directly into the tissues, thus reducing the amount of active principle used. In the pharmaceutical field, on the contrary, nanoemulsions have proved to be effective for spreading anti-bacterial or anti- fungus agents, viruses which are directly transported into the cells by the fusion of the nanoemulsion with the cell membrane.
The potentiality of nanoemulsions for eradicating viruses such as anthrax and AIDS is under study, and also as a carrier of antitumour agents.
There are numerous fields, from the food to the oil industry, in which these products could be used if the cost were lower and if they had a greater stability.
In the food industry, the small dimensions could impart particular organoleptic characteristics to creams and sauces, together with a high stability. Finally, in the oil industry, water-in-oil nanoemulsions could carry products, not transportable with oil due to their non-solubility, to areas in which large amounts of water cannot be conveyed, due to problems relating to corrosion, damage etc... In particular, nanoemulsions could be used as carriers of scale inhibitors, corrosion inhibitors or wax and as- phaltene inhibitors, or for acidic treatment of the formation. They can also be used for cleaning oil pipelines.
Their considerable stability, when suitably prepared, and the fact that the inner water is completely shielded, could make them interesting for carrying additives which are incompatible with each other or for triggering polymerization or gelation reactions in appropriate areas of the well . At present, the high cost is due to the necessity of using high energy systems, such as high pressure homogenis- ers, for obtaining them.
The so-called low energy methods are empirical and not easy to implement. In particular, obtaining water-in-oil nanoemulsions is still a problem which is not easy to solve .
Analogously to macroemulsions, for which, however, there is no standard procedure for their preparation but more or less empirical formulation criteria, nanoemulsions also suffer from the lack of scientific criteria for their formulation.
The highest critical point for the formation of nanoemulsions with respect to the corresponding macroemulsions, lies in the higher energy necessary for obtaining them, due to the very small dimensions of the droplets of the dispersed phase (smaller than 500 nm) .
The so-called low energy procedures can be carried out through particular areas of the phase diagram, with a very low interface tension, which are areas of either liquid crystals or microemulsions . It is known, for example, that nanoemulsions can be obtained through a spontaneous emulsioning by means of phase inversion, such as the classical PIT (Phase Inversion Temperature) method [K: Shinoda, H. Saito, J. Colloid In- terface Sci. 1 (1949) 311] in particular through certain areas of liquid crystals of the phase diagram [Paqui Iz- quierdo, Jin Feng, Jordi Esquena, Tharward F. Tadros, Joseph C. Dederen, Mari Jose Garcia, Nύria Azemar, Conxita Solans, Journal of Colloid and Interface Science 285 (2005) 388-394] .
In certain cases, oil-in-water nanoemulsions have been obtained by means of phase inversion [Patrick Fernandez, Valeris Andre, Jens Rieger, Angelika Kuhnle, Colloids and Surfaces A: Physicochem. Eng. Aspects 251 (2004) 53-58] by varying the water/oil ratio (catastrophic inversion, the nanoemulsions obtained are between 100 and 500 nm) or by the dilution of microemulsions [R. Pons, I. Carrera, J. Caelles, J. Rouch, P. Panizza, Advances in Colloid and Interface Science, 106, (2003) 129-146] . It is not so easy to find papers relating to the formation of water- in-oil nanoemulsions through "gently methods" [N. Uson, M.J. Garciaand C. Solans Colloids and Surfaces A: Physicochemical and Engineering Aspect, Volume 250, Issues 1-3, December 10, 2004, pages 415-421; M. Por- ras, C. Solans, C. Gonzales, A. Martinez, A. Guinart and J. M. Gutierrez Colloids and Surfaces A: Physicochemical and Engineering aspect, Volume 250, Issues 1-3, 10 December 2004, Pages 415-421; M Porras, C. Solans, C. Gonzales,A. Martinez, A. Guinart and J. M. Gitierrez Colloids and Sur- faces A: Physicochemical and Engineering Aspects, Volume 249, Issues 1-3, November 30, 2004, pages 115-118; Italian patent application nr. MI 03A002101] .
These low energy processes have the disadvantage of being set up case by case, depending on the systems used (type of surface-active agent, water, oil) .
Italian patent application nr. MI 03A002101, for example, describes a three-step low energy process for the preparation of water-in-diesel nanoemulsions, comprising the preparation of a blend of surface-active agents so as to obtain a first emulsion, transformation of the first emulsion into a second birefringent emulsion, mixing of the birefringent emulsion with diesel in order to obtain the desired nanoemulsion.
The water- in-gas oil nanoemulsions obtained through this method are practically mono-dispersed, as they comprise a reduced quantities of a composition of non- ionic surface-active agents (1 to 5% by weight; much lower than that of microemulsions) and are characterized by a high stability. A low energy process has now been found for the prepa- ration of mono-dispersed water-in-oil and oil-in-water nanoemulsions, with a high stability, having the characteristic of being simpler and with a wider applicability range with respect to those described in the known art. The process of the invention also allows the preparation of nanoemulsions with a high formation kinetics, so that they are obtained within a few hours after their dilution, whereas the method described in patent application nr. MI 03A002101 requires longer times (a few days) for their formation.
The process of the invention is based on the capacity of a system based on water and oil, of inverting the phase by varying the hydrophilie/lipophilic balancing of the surface active agents present in the system (HLB) . The inversion takes place by the dilution of a homogeneous blend (concentrated precursor) characterized by a certain HLB and an interface tension lower than 1 mN/m, in a dispersing phase (oil or water) which contains a surface- active agent capable of conferring a different HLB to the final dispersion with respect to the precursor.
It has also been found that the selection of the final HLB of the nano-emulsion can be effected on the basis of the HLB of the corresponding micro-emulsion. This micro- emulsion can be easily obtained without any particular pro- cedures, but simply by using a higher quantity of surface- active agent .
The HLB of the nanoemulsion is lower than that of the precursor in the case of water-in-oil dispersions, whereas it is higher than that of the precursor, in the case of oil-in-water dispersions. During dilution, an instantaneous phase inversion occurs, together with the formation of the nanoemulsion.
In accordance with the above, a process for the preparation of a water-in-oil or oil-in-water nanoemulsion in which the dispersed phase is distributed in the dispersing phase, in the form of droplets having a diameter ranging from 1 to 500 ran, represents a first object of the present invention, which comprises:
1) the preparation of a homogeneous water/oil blend (1) characterized by an interface tension lower than 1 mN/m, comprising water in a quantity of 30 to 70% by weight, at least two surface-active agents having a different HLB, selected from non-ionic, anionic, polymeric surface-active agents, the latter being present in such a quantity as to make the blend homogeneous;
2) the dilution of the blend (1) in a dispersing phase consisting of oil or water with the addition of a surface-active agent selected from non-ionic, anionic polymeric surface-active agents, the quantity of the dispersing phase and surface-active agent being such as to obtain a nanoemulsion having a HLB different from that of the blend (1) .
The HLB of the final nanoemulsion is selected on the basis of that of the corresponding micro-emulsion charac- terized by the same water/oil ratio as the nanoemulsion, but with a total quantity of surface-active agents such as to make the blend homogeneous by the simple addition of all the components.
In particular, when water- in-oil emulsions are to be obtained, an amount of dispersing phase and surface-active agent is used in order to obtain a nanoemulsion having a HLB higher than that of the blend (1) .
Nano-emulsions are obtained only by operating in accordance with the process of the invention: the preparation of a blend having the same final composition, but without following the procedure specified (preparation of the precursor, order of addition of the reagents, etc..) does not produce a limpid nanoemulsion, but an opaque and milky macro-emulsion characterized by droplets having dimensions well above a micron.
Homogeneous blends can be advantageously prepared, comprising from 5 to 50% by weight of surface-active agents and in which the weight ratio of the surface-active agents used gives a HLB value higher than 8, preferably between 10 and 15 for non- ionic, and over 20 for anionic surface- active agents .
The concentration of surface-active agents in the blend is in relation to the final water/oil amount which is to be dispersed. The weight proportion between the concentration of the surface-active agents in the blend and the amount of water/oil to be dispersed, can vary from 0.07 to 3.5, preferably from 0.1 to 2.
The surface-active agents used for the preparation of the blend can be selected from non- ionic, anionic, poly- meric surface-active agents, preferably non- ionic and polymeric surface-active agents.
Blends can be suitably prepared comprising a first surface-active agent selected from non-ionic lipophilic surface-active agents (A type) , a second surface-active agent selected from non-ionic hydrophilic surface-active agents (B type) , a third surface-active agent selected from polymeric surface-active agents (C type) , the composition of surface-active agents (A) + (B) + (C) having a HLB ranging from 8 to 16, preferably from 10 to 15. Preferred formulations include a lipophilic non- ionic surface-active agent of the fatty acid ester group having a HLB higher than 11 and a non- ionic, polymeric surface-active agent with a HLB varying from 4 to 14.
The mix has the appearance of a limpid to translucent solution and is characterized by a high stability as it al- lows nanoemulsions to be prepared by dilution even up to a year after its preparation. The blend maintains its properties even after being subjected to freezing.
The preparation can be effected at a temperature rang- ing from 5 to 600C.
In practice, in order to prepare the homogeneous precursor blends of nano-emulsions, the mixture of surface- active agents, selected from non-ionic, anionic and polymeric surface-active agents, is dissolved in oil so as to obtain the desired HLB, and when the dissolution is complete, the water solution is added under stirring.
The aqueous solution can be deionised water or water with additives. At the end of the addition, the blend will appear homogeneous and limpid. This precursor blend can be used for preparing water-in-oil and oil-in-water nanoemulsions .
In order to formulate water-in-oil nanoemulsions, the precursor mix is added, at room temperature, slowly, and under stirring to a solution consisting of oil and the lipophilic surface-active agent selected from non- ionic and polymeric surface-active agents.
In order to formulate oil-in-water nanoemulsions, the precursor mix is added, at room temperature, slowly, and under stirring to a solution consisting of an aqueous solu- tion and the hydrophilic surface-active agent selected from non- ionic and polymeric surface-active agents.
Normally, the nanoemulsion preparation is effected at a temperature ranging from 5 to 600C.
The complete transformation into the final nano- emulsion is revealed by the limpid/translucent appearance and by the monomodal distribution of the dispersed phase droplets.
The nanoemulsions obtained through the process of the invention can be formulated with a different content of dispersed water or oil, they are stable for over 6 months, do not require particular care for their preservation, and maintain their characteristics up to a temperature of 700C.
It is normally possible to prepare nanoemulsions having a wider concentration range of dispersed phase, by means of a sole formulation of a homogeneous blend (or precursor) .
When water-in-oil emulsions are to be obtained, the dilution is effected using an amount of dispersing phase and surface-active agent such as to obtain a nanoemulsion having a HLB at least 0.5 units lower with respect to that of the homogeneous blend (1) .
When the surface-active agent, which is dissolved in the oily phase, is selected from non- ionic lipophilic surface-active agents, preferably non- ionic surface-active agents of the group of esters of fatty acids, and the homo- geneous blend is prepared with non- ionic and polymeric sur- face-active agents, the nanoemulsion must have a HLB 0.8 - 5 units lower.
When oil-in-water emulsions are to be obtained, the dilution is effected with a quantity of dispersing phase and surface-active agent such as to obtain a nanoemulsion having a HLB at least 0.5 units higher with respect to that of the homogeneous blend (1) . When the surface-active agent which is dissolved in the aqueous phase is selected from non-ionic hydrophilic surface-active agents, preferably from non- ionic surface-active agents of the group of alkyl glucosides and the homogeneous blend is prepared with non- ionic and polymeric surface-active agents, the nanoemulsion should have a HLB 0.8 -5 units higher.
Water-in-oil nanoemulsions can be prepared by operating according to the procedure of the invention, having a HLB value ranging from 6 to 14, comprising a water content ranging from 1 to 30%, and a total amount of surface-active agents ranging from 0.1 to 20%, the complement to a hundred being oil. Water- in-oil nanoemulsions can preferably be prepared with a HLB value ranging from 9 to 13, comprising a water content ranging from 5 to 25% and total surface-active agents ranging from 1.5 to 12%, the complement to a hundred being oil. Oil-in-water nanoemulsions can also be conveniently prepared having a HLB value higher than 10, comprising an oil content ranging from 1% to 30% and total surface-active agents from 0.1 to 20%, the complement to a hundred being oil. Oil-in-water nanoemulsions can be preferably prepared with a HLB value ranging from 11 to 16, comprising an oil content ranging from 5 to 25% and total surface-active agents from 1.5 to 12%, the complement to a hundred being water. Any polar or apolar oil, preferably insoluble in water, can be used for the purposes of the present invention.
The oil is preferably selected from the group of linear or branched hydrocarbons, such as, for example, dodecane, or complex mixtures of hydrocarbons such as gas oil, kero- sene, soltrol, mineral spirits.
As far as the water which can be used for the preparation of the nanoemulsions of the present invention is concerned, this can be of any origin.
In the case of applications in the oil industry, it is preferable, for obvious economical reasons, for the water to be available close to the nanoemulsion preparation site of the present invention.
Different types of water can be used, such as deminer- alized water, saltwater, water with additives. In principle, any additive can be englobed in the nano- emulsions and they can be used in the food, oil, cosmetic, pharmaceutical and fuel industries, where they are used as additive carriers.
In particular the nanoemulsions of the present inven- tion can be suitably used in the oil industry, for the injection of additives into the well, which cannot be carried with the oil (as they are not soluble) or for the injection of acid solutions in areas which cannot be reached by large amounts of water due to problems relating to corrosion, damage, etc..
The nanoemulsions of the invention can also be formulated so as to contemporaneously carry two different additives, incompatible with each other, such as, for example, a scale inhibitor in aqueous phase (dispersed phase) and a wax/asphaltene inhibitor in organic phase (the two additives are incompatible as they are soluble in different solvents) , or a scale inhibitor in aqueous phase and a corrosion inhibitor in organic phase (the two additives are chemically incompatible) . Finally, they can be used for the cleaning of oil pipelines.
When used upstream, the nanoemulsions must not damage the formation and, under suitable conditions, release the dispersed phase containing the additives .
The nanoemulsions can also be formulated using aqueous solutions as dispersed phase. These aqueous solutions can consist of salt solutions, such as, for example, chlorides, bromides, sulphates, phosphates of alkaline metals (sodium, potassium) , alkaline-earth metals (calcium) or transition metals (silver, cobalt, nickel, copper, zinc, iron) . The aqueous solutions can also consist of hydro-soluble additive solutions, such as, for example, urea, oxygenated water, scale inhibitors (such as, for example, phosphono- carboxylic acids, amino phosphonic acids, organic sulphates, etc.. ) . The aqueous solutions can contain from 0.1 to 50% by weight of additive and preferably from 5 to 20%.
In particular, when scale inhibitors are used, these are normally present at concentrations ranging from 5 to 15%. Nanoemulsions containing water with additives are normally prepared by diluting a precursor already containing the desired additive solution in the oily dispersing phase containing the lipophilic surface-active agent.
The following examples are provided for a better under- standing of the present invention. EXAMPLES
In the following examples, the procedures are described for preparing water- in-oil nanoemulsions with increasing quantities of dispersed water. Example 1 Formulation of the precursor.
The precursor suitable for the formulation of water-in- oil nanoemulsions, in which the oil is dodecane and the dispersed phase is deionised water, can be formulated ac- cording to the following procedure.
0.177 g of Atlox 4914 (Uniqema) , 1.563 gr of Span 80 (Fluka) and 3.588 gr. of Glucopone 600 CS UP (Fluka, 50% water solution) are weighed in a single container and dissolved in 8.233 gr. of dodecane. When the dissolution is complete, 6.439 gr. of deionised water are added under vigorous stirring by means of a magnetic stirrer. The precursor is characterized by a HLB value of 10.8 and is indefinitely stable.
Example 2 Formulation of nanoemulsions with 6.8% of water as dispersed phase.
0.073 gr of Span 80 are dissolved in 8.275 gr of dodecane in order to obtain 10 gr of nanoemulsion. 1.652 gr of precursor, as prepared in example 1, are slowly added under stirring (magnetic stirrer) to this solution. The emulsion obtained has a transparent-translucent appearance, it is characterized by a HLB value of 9.6 and has the following composition: total surface-active agents = 3.65% by weight dodecane = 89.55% by weight water = 6.8% by weight
The nanoemulsion thus formulated has droplets of dispersed phase around 30 - 40 nm, a polydispersity index lower than 0.1 and it is stable for over a year. Example 3
Formulation of nanoemulsions with 10% of water as dispersed phase .
0.096 gr of Span 80 are dissolved in 7.475 gr of dode- cane in order to obtain 10 gr of nanoemulsion. 2.429 gr of precursor, as prepared in example 1, are slowly added under stirring (magnetic stirrer) to this solution. The emulsion obtained has a transparent-translucent appearance, it is characterized by a HLB value of 9.7 and has the following composition: total surface-active agents = 5.25% by weight dodecane = 84.75% by weight water = 10% by weight
The nanoemulsion thus formulated has droplets of dispersed phase around 30 - 50 nm, a polydispersity index lower than 0.15 and is stable for over a year. Example 4
Formulation of nanoemulsions with 20% of water as dispersed phase.
0.131 gr of Span 80 are dissolved in 5.010 gr of dode- cane in order to obtain 10 gr of nanoemulsion. 4.858 gr of precursor, as prepared in example 1, are slowly added under stirring (magnetic stirrer) to this solution. The emulsion obtained has a transparent-translucent appearance, it is characterized by a HLB value of 10 and has the following composition: total surface-active agents = 9.9% by weight dodecane = 70.1% by weight water = 20% by weight
The nanoemulsion thus formulated has droplets of dis- persed phase around 40 - 60 nm, a polydispersity index lower than 0.2 and it is stable for over six months .
In the following series of examples the procedures are described for preparing water-in-oil nanoemulsions containing additive solutions as dispersed phase, with different concentrations of additives and dispersed phase.
Example 5.
Preparation of a precursor containing a 5% by weight solution of a hydrosoluble additive.
The precursor suitable for the formulation of water- in- oil nanoemulsions, in which the oil is dodecane and the dispersed phase is an aqueous solution containing 5% by weight of a scale inhibitor, can be formulated according to the following procedure.
0.151 gr of Atlox 4914 (Unigema) , 1.191 gr of Span 80 (Fluka) and 3.342 gr of Glucopone 600 CS UP (Fluka, 50% so- lution in water) are weighed in a single container and are dissolved in 8.153 gr of dodecane . When the dissolution is complete, 6.823 gr of a 5% by weight aqueous solution of an scale inhibitor (for example a phosphino- polycarboxylic acid or a sodium phosphono-carboxylate) are added under vigorous stirring on a magnetic stirrer. The blend thus obtained is characterized by a HLB value of 11.35 and is indefinitely stable. Example 6 Preparation of a precursor containing a 10% weight solution of a hydrosoluble additive.
The precursor suitable for the formulation of water-in- oil nanoemulsions, in which the oil is dodecane and the dispersed phase is an aqueous solution containing 10% by weight of an scale inhibitor, can be formulated according to the following procedure.
0.151 gr of Atlox 4914 (Unigema) , 1.023 gr of Span 80 (Fluka) and 3.676 gr of Glucopone 600 CS UP (Fluka, 50% solution in water) are weighed in a single container and are dissolved in 7.828 gr of dodecane. When the dissolution is complete, 6.656 gr of a 10% weight aqueous solution of an scale inhibitor (for example a phosphino-polycarboxylic acid or a sodium phosphono-carboxylate) are added under vigorous stirring on a magnetic stirrer. The blend thus ob- tained is characterized by a HLB value of 12 and is indefi- nitely stable. Example 7
Preparation of a precursor containing a 15% weight solution of a hydrosoluble additive. The precursor suitable for the formulation of water- in- oil nanoemulsions, in which the oil is dodecane and the dispersed phase is an aqueous solution containing 15% by- weight of a scale inhibitor, can be formulated according to the following procedure. 0.151 gr of Atlox 4914 (Unigema) , 0.869 gr of Span 80 (Fluka) and 3.985 gr of Glucopone 600 CS UP (Fluka, 50% solution in water) are weighed in a single container and are dissolved in 7.519 gr of dodecane. When the dissolution is complete, 6.501 gr of a 15% by weight aqueous solution of a scale inhibitor (for example a phosphino-polycarboxylic acid or a sodium phosphono-carboxylate) are added under vigorous stirring on a magnetic stirrer. The blend thus obtained is characterized by a HLB value of 12.60 and is indefinitely stable. Example 8
Formulation of nanoemulsions with the addition in aqueous phase of scale inhibitors .
0.081 gr. of Span 80 are dissolved in 3.094 gr of dodecane, in order to obtain 10 gr of nanoemulsion. 2.826 gr of precursor, as prepared in example 5, are added to this solution, slowly and under stirring (magnetic stirrer) . The emulsion obtained has a transparent-translucent appearance, it is characterized by a HLB value of 10.30 and has the following composition: total surface-active agents = 8.57% by weight dodecane = 71.09% by weight water = 19.53% by weight additive = 0.83% by weight
The nanoemulsion thus formulated has droplets of dis- persed phase around 40 - 60 nm, a polydispersity index lower than 0.2 and it is stable for over six months. Example 9
Formulation of nanoemulsions with the addition in aqueous phase of scale inhibitors. 0.074 gr. of Span 80 are dissolved in 8.3 gr of dodecane, in order to obtain 10 gr of nanoemulsion. 1.6 gr of precursor, as prepared in example 6, are added to this solution, slowly and under stirring (magnetic stirrer) . The emulsion obtained has a transparent-translucent appearance, it is characterized by a HLB value of 10.35 and has the following composition: total surface-active agents = 3.25% by weight dodecane = 89.7% by weight water = 6.5% by weight additive = 0.55% by weight The nanoemulsion thus formulated has droplets of dispersed phase around 40 - 60 nm, a polydispersity index lower than 0.2 and it is stable for over six months. Example 10 Formulation of nanoemulsions with the addition in aqueous phase of scale inhibitors.
0.101 gr. of Span 80 are dissolved in 7.5 gr of dode- cane, in order to obtain 10 gr of nanoemulsion. 2.4 gr of precursor, as prepared in example 6, are added to this so- lution, slowly and under stirring (magnetic stirrer) . The emulsion obtained has a transparent-translucent appearance, it is characterized by a HLB value of 10.45 and has the following composition: total surface-active agents = 4.75% by weight dodecane = 84.71% by weight water = 9.72% by weight additive = 0.83% by weight
The nanoemulsion thus formulated has droplets of dispersed phase around 40 - 60 nm, a polydispersity index lower than 0.2 and it is stable for over six months. Example 11
Formulation of nanoemulsions with the addition in aqueous phase of scale inhibitors .
0.134 gr. of Span 80 are dissolved in 6.3 gr of dode- cane, in order to obtain 10 gr of nanoemulsion. 3.5 gr of precursor, as prepared in example 6, are added to this solution, slowly and under stirring (magnetic stirrer) . The emulsion obtained has a transparent-translucent appearance, it is characterized by a HLB value of 10.6 and has the fol- lowing composition: total surface-active agents = 6.84% by weight dodecane = 77.68% by weight water = 14.27% by weight additive = 1.21% by weight The nanoemulsion thus formulated has droplets of dispersed phase around 40 - 60 nm, a polydispersity index lower than 0.2 and it is stable for over six months. Example 12
Formulation of nanoemulsions with the addition in aqueous phase of scale inhibitors.
0.157 gr. of Span 80 are dissolved in 5.134 gr of dodecane, in order to obtain 10 gr of nanoemulsion. 4.709 gr of precursor, as prepared in example 6, are added to this solution, slowly and under stirring (magnetic stirrer) . The emulsion obtained has a transparent-translucent appearance, it is characterized by a HLB value of 10.7 and has the following composition: total surface-active agents = 8.91% by weight dodecane = 70.41% by weight water = 19.07% by weight additive = 1.62% by weight
The nanoemulsion thus formulated has droplets of dispersed phase around 40 - 60 nm, a polydispersity index lower than 0.2 and it is stable for over six months. Example 13
Formulation of nanoemulsions with the addition in aqueous phase of scale inhibitors.
0.070 gr. of Span 80 are dissolved in 3.105 gr of do- decane, in order to obtain 10 gr of nanoemulsion. 2.826 gr of precursor, as prepared in example 7, are added to this solution, slowly and under stirring (magnetic stirrer) . The emulsion obtained has a transparent-translucent appearance, is characterized by a HLB value of 11.54 and has the following composition: total surface-active agents = 8.62% by weight dodecane = 70.35% by weight water = 18.61% by weight additive = 2.41% by weight
The nanoemulsion thus formulated has droplets of dis- persed phase around 40 - 60 nm, a polydispersity index lower than 0.2 and it is stable for over six months .
In the following series of examples the procedures are described for preparing water- in-oil nanoemulsions with different types of oil as continuous phase. Example 14 Formulation of nanoemulsions with the addition in aqueous phase of scale inhibitors, using gas oil, or sol- trol or mineral spirits as continuous phase.
Nanoemulsions can be obtained by indifferently using one of the above-mentioned hydrocarbons by applying the following procedure.
0.085 gr. of Span 80 are dissolved in 3.090 gr of die- sel or soltrol or mineral spirits to obtain 6 gr of nanoe- mulsion. 2.826 gr of precursor, prepared with the same pro- cedure described in example 6, but using gas oil or soltrol or mineral spirits as organic phase, are added to this solution, slowly and under stirring (magnetic stirrer) . The emulsion obtained has a transparent-translucent appearance, it is characterized by a HLB value of 10.8 and has the fol- lowing composition: total surface-active agents = 8.7% by weight hydrocarbon = 70.6% by weight water = 19.1% by weight scale inhibitor = 1.6% by weight The nanoemulsion thus formulated has droplets of dispersed phase around 40 - 60 nm, a polydispersity index lower than 0.2 and it is stable for over six months . Example 15
Formulation of nanoemulsions with the addition in aqueous phase of scale inhibitors, using kerosene as con- tinuous phase .
0.068 gr. of Span 80 are dissolved in 3.106 gr of kerosene to obtain 6 gr of nanoemulsion. 2.826 gr of precursor, prepared with the same procedure described in exam- pie 6, but using kerosene as organic phase, are added to this solution, slowly and under stirring (magnetic stirrer) . The emulsion obtained has a transparent-translucent appearance, it is characterized by a HLB value of 11.0 and has the following composition: total surface-active agents = 8.5% by weight hydrocarbon = 70.8% by weight water = 19.1% by weight scale inhibitor = 1.6% by weight
The nanoemulsion thus formulated has droplets of dis- persed phase around 40 - 60 ran, a polydispersity index lower than 0.2 and it is stable for over six months.
In the following series of examples the procedures are described for preparing water-in-oil nanoemulsions with the addition of additives in both the continuous and dispersed phase.
Example 16
Preparation of the precursor with the addition in aqueous phase of scale inhibitors and in the organic phase of wax/asphaltene inhibitors. The precursor suitable for the formulation of water-in- oil nanoemulsions, in which oil is a 10% solution by weight of a wax/asphaltene inhibitor (FX 1972 of Ondeo Nalco) in dodecane and the dispersed phase is an aqueous solution containing 10% by weight of a scale inhibitor, can be for- mulated according to the following procedure.
0.151 gr of Atlox 4914 (Uniqema) , 0.946 gr of Span 80 (Fluka) and 3.831 gr of Glucopone 600 CS UP (Fluka 50% water solution) are weighed in a single container and are dissolved in 7.836 gr. of a solution of wax/asphaltene in- hibitor in dodecane. When the dissolution is complete, 6.579 gr. of a 10% by weight water solution of a scale inhibitor (for example polycarboxylic phosphine acid or a sodium phosphono-carboxylate) are added under vigorous stirring on a magnetic stirrer. The blend thus obtained, char- acterized by a HLB value of 12.30 is indefinitely stable. Example 17
Formulation of nanoemulsions with the addition in aqueous phase of scale inhibitors and in the organic phase with wax/asphaltene inhibitors. 0.097 gr of Span 80 are dissolved in 2.549 gr of a 10% by weight solution of wax/asphaltene inhibitor in dodecane in order to obtain 5 gr of nanoemulsion. 2.355 gr of a precursor, as prepared in example 16, are slowly added under stirring (magnetic stirrer) to this solution. The emulsion obtained has a transparent-translucid appearance, it is characterized by a HLB value of 10.75 and has the following composition: total surface-active agents = 9.4% by weight dodecane = 62.6% by weight water = 19.5% by weight additive in aqueous phase (scale inhibitor) = 1.6% by weight additive in organic phase (wax inhibitor) = 6.9% by weight. The nanoemulsion thus formulated has droplets of dispersed phase around 30 - 40 nm, a polydispersity index lower than 0.2 and it is stable for over six months.
Example 18
Formulation of nanoemulsions with the addition in aque- ous phase of scale inhibitors and in the organic phase with corrosion inhibitors.
0.157 gr of Span 80 are dissolved in 5.134 gr of a solution containing 1300 ppm of a corrosion inhibitor (Inicor R200 of Lamberti) in dodecane in order to obtain 10 gr of nanoemulsion. 4.709 gr of a precursor prepared by using additive-free dodecane as organic phase and, as aqueous phase, a 10% solution of a scale inhibitor, as described in example 6, are slowly added under stirring (magnetic stirrer) to this solution. The emulsion obtained has a trans- parent-translucid appearance, it is characterized by a HLB value of 10.70 and has the following composition: total surface-active agents = 8.9% by weight dodecane = 70.4% by weight water = 19.1% by weight additive in aqueous phase (scale inhibitor) = 1.6% by weight additive in organic phase (corrosion inhibitor) = 700 ppm.
The nanoemulsion thus formulated has droplets of dis- persed phase around 30 - 40 nm, a polydispersity index lower than 0.2 and it is stable for over six months.
In the following series of examples the procedures are described for preparing oil-in-water emulsions.
Example 19 Formulation of the precursor for oil-in-water nanoemul- sions .
The precursor suitable for the formulation of oil-in- water nanoemulsions, in which the oil is dodecane and the dispersed phase is deionised water, can be formulated ac- cording to the following procedure.
0.177 g of Atlox 4913 (Uniqema) , 1.284 gr of Span 80
(Fluka) and 4.147 gr. of Glucopone 600 CS UP (Fluka, 50% water solution) are weighed in a single container and are dissolved in 8.233 gr. of dodecane. When the dissolution is complete, 6.160 gr. of deionised water are added under vig- orous stirring by means of a magnetic stirrer. The precursor is characterized by a HLB value of 12 and is indefinitely stable.
Example 20 Formulation of oil-in-water nanoemulsions with 6.8% of dodecane as dispersed phase.
0.174 gr of Span 80 are dissolved in 4.8 gr of water. 1.0 gr of a precursor as prepared in example 19, are slowly added under stirring (magnetic stirrer) to this solution. The emulsion obtained has a transparent-translucent appearance, it is characterized by a HLB value of 13.5 and has the following composition: total surface-active agents = 4.4% by weight dodecane = 6.8% by weight water = 88.8% by weight
The nanoemulsion thus formulated has droplets of dispersed phase around 30 - 40 nm, a polydispersity index lower than 0.2 and it is stable for over six months .
Some comparative examples are provided hereunder which demonstrate that nanoemulsions are not obtained if the procedures claimed in this patent are not followed. Example 21 (comparative)
Mixing of the ingredients of the nanoemulsion corresponding to example 4 (20% aqueous phase) without following the procedure indicated in the patent. 0.043 gr of Atlox 4914 (Uniqema) , 0.51 gr of Span 80 (Fluka) and 0.88 gr of Glucopone 600 CS UP (Fluka, 50% water solution) are dissolved in 7 gr of dodecane and 1.57 gr of water are added. A suspension is obtained having the same composition as the nanoemulsion of example 4 and the same HLB = 10, but the appearance is opaque and milky and the dispersed phase has droplets having dimensions of over 1 micron.
Composition of the suspension: total surface-active agents = 9.9% dodecane = 70.1% water = 20% Example 22 (comparative)
Preparation of a nanoemulsion having a non-optimal fi- nal HLB.
The precursor blend having a HLB of 10.8 is prepared as in example 1. The water-in-oil nanoemulsion containing 20% of dispersed phase is formulated however so as to be characterised by a HLB of 9.6 instead of HLB = 10, as indi- cated in example 4. 0.214 gr of Span 80 (Fluka) are dissolved in 4.928 gr of dodecane. 4,858 gr of a precursor blend prepared as in example 1 are slowly added under stirring to the solution thus obtained. A suspension is obtained characterised by a HLB of 9.6 but having an opaque and milky appearance, with the dimensions of the dispersed phase droplets higher than 500 nm. Suspension composition: total surface-active agents = 10.7% dodecane = 69.3% water = 20%
Example 23 (comparative)
Preparation of a nanoemulsion by the dilution of a non- homogeneous precursor blend
0.177 gr of Atlox 4914 (Uniqema) , 1.744 gr of Span 80 (Fluka) and 3.226 gr. of Glucopone 600 CS UP (Fluka, 50% water solution) are weighed in a single container and are dissolved in 8.233 gr. of dodecane in order to prepare the precursor blend. When the dissolution is complete, 6.620 gr. of deionised water are added under vigorous stirring by means of a magnetic stirrer. The precursor is characterized by a HLB value of 10.2 and is separated into two phases. 0.033 of Span 80 (Fluka) are dissolved in 5.100 gr of dodecane. 4.900 gr of a precursor mix prepared as described in this example, are slowly added, under stirring to the solu- tion thus obtained.
A suspension is obtained, characterised by a HLB of 10, but having an opaque and milky appearance, with the tendency of depositing into two phases. suspension composition : total surface-active agents = 9% dodecane = 71% water = 20%. Example 24
Example of the preparation of a micro-emulsion with the aim of defining the HLB suitable for the formulation of the nanoemulsion.
In order to obtain a homogeneous micro-emulsion with a HLB of 9.6, containing 7% of aqueous phase, a concentration of surface-active agent of at least 7% is necessary. In par- ticular, 0.763 gr of Span 80 (Fluka) , 1.134 gr of Glucopone
CS UP (Fluka 50% water solution) and 0.070 gr of Atlox 4914
(Uniqema) are dissolved in 17.2 gr of dodecane and 0.81 gr of water are added, under stirring until a homogeneous product is obtained. A limpid micro-emulsion is thus ob- tained having a HLB of 9.6 with a composition equal to: total surface-active agents = 7% water = 7% dodecane = 86% Nanoemulsion applications upstream: Example 25
Behaviour to temperature:
Nanoemulsions prepared according to the procedure described in example 6, with a weight composition equal to 70.4% of dodecane, 19.1% of water, 8.9% of surface-active agents and 1.6% of scale inhibitor of the group of phos- phono-succinic acids, are charged into an autoclave at a pressure of 30 bars and maintained at temperatures of 6O0C, 800C, 1000C for 8 hours.
The nanoemulsion remains unaltered up to a temperature of 800C, when it begins to show a slight separation of the aqueous phase. At a temperature of 1000C, the aqueous phase is completely separated, allowing the release of the hydro- soluble additive, which follows the same destiny as the aqueous phase . Example 26
Behaviour to flushing on a porous medium:
A column having a height of 20 cm and a diameter of 1.9 cm is packed with quartzite having a particle-size greater than 230 mesh and flushed with dodecane at a tem- perature of 900C. The initial permeability to dodecane proves to be 55 mD, with a pore volume (PV) equal to 28.9 cm3.
180 ml (equal to 6.2 PV) of a nanoemulsion prepared according to the procedure described in example 6, with a composition by weight equal to 70.4% of dodecane, 19.1% of water, 8.9% of surface-active agents and 1.6% of a scale inhibitor of the group of phosphono-succinic acids is flushed in the quartzite column at a flow-rate of 120 mg/h and a temperature of 900C, maintaining an overpressure of 2.8 bars. Under these conditions, the nanoemulsion sepa- rates the aqueous phase containing the scale inhibitor, allowing it to be released and deposited on the quartzite.
At the end, the column is flushed again with dodecane until the complete separation of the nanoemulsion, and the permeability to dodecane is determined again.
During the flushing of the nanoemulsion, the pressure
differential (Δp) undergoes a slight increase, passing from 1.9 to 3.1, due to the greater viscosity of the emulsion with respect to the dodecane, the final permeability to do- decane, however, is not modified with respect to its initial value, confirming that the nanoemulsion is filterable and non-damaging.
At the end of the test, the quartzite contained in the column is discharged and analyzed to evaluate the adsorp- tion of the inhibitor, which proves to be equal to 0.6 mg/g quartzite (4% with respect to the total) , typical of scale inhibitors of this group (REF: M. Andrei, A. Malandrino, Petrol. Sci Technol., 2003, 21(7-8)1295-1315).

Claims

1. A process for the preparation of a water- in-oil or oil-in-water nanoemulsion wherein the dispersed phase is distributed in the dispersing phase in the form of droplets having a diameter ranging from 1 to 500 nm, comprising:
1) the preparation of a homogeneous water/oil blend
(I) characterized by an interface tension lower than 1 mN/m, comprising water in an amount of 30 to 70% by weight, at least two surface-active agents having a different HLB, selected from non-ionic, anionic, polymeric surface-active agents, said surface-active agents being present in such a quantity as to make the blend homogeneous ; 2) the dilution of the blend (I) in a dispersing phase consisting of oil or water with the addition of a surface-active agent, selected from non-ionic, anionic, polymeric surface-active agents, the quantity of the dispersing phase and surface-active agent being such as to obtain a nanoemulsion having a HLB different from that of the blend (I) .
2. The process according to claim 1, wherein the HLB of the final nanoemulsion is selected on the basis of that of the corresponding micro-emulsion characterized by the same water/oil ratio of the nanoemulsion but with a higher total quantity of surface-active agents.
3. The process according to claim 1, wherein when water- in-oil emulsions are to be obtained, a quantity of dispersing phase and surface-active agent is used so as to obtain a nanoemulsion having a HLB lower than that of the blend (1) .
4. The process according to claim 1, wherein when oil-in- water emulsions are to be obtained, a quantity of dispersing phase and surface-active agent is used so as to obtain a nanoemulsion having a HLB higher than that of the blend (1) .
5. The process according to claim 1, wherein the homogeneous water-in-oil blend (1) is prepared by dissolving the surface-active agents in the oily phase and, when the dissolution is complete, adding water under vigorous stirring, until complete homogenization.
6. The process according to claim 1, wherein the homogeneous blend (1) comprises from 5 to 50% by weight of surface-active agents and the weight ratio between the surface-active agents produces a HLB value higher than 8.
7. The process according to claim 6, wherein the surface- active agents are selected from non-ionic surface- active agents and the weight ratio between the sur- face-active agents produces a HLB ranging from 10 to
15 .
8. The process according to claim 6, wherein the surface- active agents are selected from anionic surface-active agents and the weight ratio between the surface-active agents produces a HLB higher than 20.
9. The process according to claim 6, wherein the weight proportion between the concentration of surface-active agents in the blend and the quantity of water/oil to be dispersed varies from 0.07 to 3.5.
10. The process according to claim 9, wherein the weight proportion between the concentration of surface-active agents in the blend and the quantity of water/oil to be dispersed varies from 0.1 to 2.
11. The process according to claim 1, wherein the surface- active agents having a different HLB are selected from non-ionic and polymeric surface-active agents.
12. The process according to claim 1, wherein the surface- active agents having a different HLB are selected from the group consisting of a first surface-active agent selected from non-ionic lipophilic surface-active agents (type A) , a second surface-active agent selected from non- ionic hydrophilic surface-active agents (type B) , a third surface-active agent selected from polymeric surface-active agents (type C) , the composition of surface-active agents (A) + (B) + (C) having a HLB ranging from 8 to 16.
13. The process according to claim 12, wherein the composition of surface-active agents (A) + (B) + (C) has a HLB ranging from 10 to 15.
14. The process according to claim 1, wherein the surface- active agents having a different HLB consist of a non- ionic lipophilic surface-active agent of the group of esters of fatty acids with a HLB lower than 11, a non- ionic hydrophilic surface-active agent of the group of alkyl glucosides with a HLB higher than 11 and a non- ionic polymeric surface-active agent with a HLB varying from 4 to 14.
15. The process according to claim 1, wherein the water- in-oil nanoemulsion is prepared by dissolving a lipo- philic surface-active agent selected from non- ionic and polymeric surface-active agents in oil and slowly adding the homogeneous blend (1) under stirring.
16. The process according to claim 1, wherein the oil-in- water nanoemulsion is prepared by dissolving a hydro- philic surface-active agent selected from non-ionic and polymeric surface-active agents in water and slowly adding the homogeneous blend (1) under stirring.
17. The process according to claim 1, wherein the prepara- tion of the nanoemulsion is effected at a temperature ranging from 5°C to 600C.
18. The process according to claim 3, wherein a quantity of dispersing phase and surface-active agent is used so as to obtain a nanoemulsion having a HLB at least 0.5 units lower with respect to that of the blend (1) .
19. The process according to claim 18, wherein when the homogeneous blend comprises non-ionic and polymeric surface-active agents and the dilution is effected with a dispersing phase consisting of oil containing a non-ionic surface-active agent of the group of esters of fatty acids, a quantity of dispersing phase and surface-active agent is used so as to obtain a nanoemulsion having a HLB at least 0.8 - 5 units lower.
20. The process according to claim 4, wherein a quantity of dispersing phase and surface-active agent is used so as to obtain a nanoemulsion having a HLB 0.5 units higher with respect to that of the blend (1) .
21. The process according to claim 20, wherein when the homogeneous blend comprises non- ionic and polymeric surface-active agents and the dilution is effected with a dispersing phase consisting of water containing a non-ionic surface-active agent of the group of alkyl glucosides, a quantity of dispersing phase and surface-active agent is used so as to obtain a nanoemul- sion having a HLB at least 0.8 - 5 units higher.
22. Water-in-oil nanoemulsions, obtained by means of the process according to claim 1, having a HLB value ranging from 6 to 14, and comprising a quantity of water which varies from 1% to 30%, total surface-active agents from 0.1% to 20%, the complement to 100 consisting of oil.
23. The nanoemulsions according to claim 22, having a HLB value ranging from 9 to 13, and comprising a quantity of water which varies from 5% to 25%, total surface- active agents from 1.5% to 12%, the complement to 100 consisting of oil.
24. Oil-in-water nanoemulsions, obtained by means of the process according to claim 1, having a HLB value higher than 10 and comprising a quantity of oil which varies from 1% to 30%, total surface-active agents from 0.1% to 20%, the complement to 100 consisting of water.
25. The nanoemulsions according to claim 24, having a HLB value ranging from 11 to 16, and comprising a quantity of oil which varies from 5% to 25%, total surface- active agents from 1.5% to 12%, the complement to 100 consisting of water.
26. The process according to claim 1, wherein the oil for the preparation of the water-in-oil or oil-in-water nanoemulsion can be selected from any polar or apolar oil.
27. The process according to claim 26, wherein the oil is selected from the group consisting of linear or branched hydrocarbons or complex hydrocarbon blends .
28. The process according to claim 27, wherein the oil is selected from the group consisting of dodecane, die- sel, kerosene, soltrol, mineral spirits.
29. The process according to claim 1, wherein the water for the preparation of the water- in-oil or oil-in- water nanoemulsion can be selected from demineralised water, saltwater, water containing additives.
30. Use of the nanoemulsions according to claims 22-25, as additive carriers, in food, oil industry, cosmetic, pharmaceutical industries and in the fuel sector.
31. Use according to claim 30, wherein, in the oil industry, the additives are selected from scale inhibitors, corrosion inhibitors, wax and asphaltene inhibitors, acid solutions.
32. Use according to claim 30, wherein the additives are selected from additives which are different and incompatible with each other.
33. Use according to claim 32, wherein the additives are a scale inhibitor, and a wax and asphaltene inhibitor or a scale inhibitor and a corrosion inhibitor.
PCT/EP2007/002863 2006-03-31 2007-03-28 Process for the preparation of water-in-oil and oil-in-water nanoemulsions Ceased WO2007112967A1 (en)

Priority Applications (11)

Application Number Priority Date Filing Date Title
CN200780016432XA CN101443436B (en) 2006-03-31 2007-03-28 Process for the preparation of water-in-oil and oil-in-water nanoemulsions
EP07723805.3A EP2001981B1 (en) 2006-03-31 2007-03-28 Process for the preparation of water-in-oil and oil-in-water nanoemulsions
US12/294,552 US8431620B2 (en) 2006-03-31 2007-03-28 Process for the preparation of water-in-oil and oil-in-water nanoemulsions
ES07723805T ES2781798T3 (en) 2006-03-31 2007-03-28 Procedure for preparing water-in-oil and oil-in-water nanoemulsions
JP2009501962A JP5694659B2 (en) 2006-03-31 2007-03-28 Preparation of water-in-oil and oil-in-water nanoemulsions
CA2646175A CA2646175C (en) 2006-03-31 2007-03-28 Process for the preparation of water-in-oil and oil-in-water nanoemulsions
KR1020087026798A KR101411754B1 (en) 2006-03-31 2007-03-28 Process for preparation of water-in-oil and oil-in-water nanoemulsions
IL194255A IL194255A (en) 2006-03-31 2008-09-22 Process for the preparation of water-in-oil or oil-in-water nanoemulsions, water-in-oil and oil-in-water nanoemulsions obtained by such process and use of such nanoemulsions as additive carriers in food, oil industry, cosmetics, pharmaceutical industries and in the fuel sector
NO20084312A NO345201B1 (en) 2006-03-31 2008-10-15 LOW ENERGY PROCEDURE FOR MANUFACTURE OF WATER-IN-OIL AND OIL-IN-WATER NANOEMULATIONS
US13/845,515 US9884299B2 (en) 2006-03-31 2013-03-18 Process for the preparation of water-in-oil and oil-in-water nanoemulsions
CY20201100328T CY1124094T1 (en) 2006-03-31 2020-04-07 PROCEDURE FOR THE PREPARATION OF WATER-IN-OIL AND OIL-IN-WATER NANOEMULSIONS

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
IT000618A ITMI20060618A1 (en) 2006-03-31 2006-03-31 PROCEDURE FOR THE PREPARATION OF NANOEMULSIONS WATER ION OIL AND OIL IN WATER
ITMI2006A000618 2006-03-31

Related Child Applications (2)

Application Number Title Priority Date Filing Date
US12/294,552 A-371-Of-International US8431620B2 (en) 2006-03-31 2007-03-28 Process for the preparation of water-in-oil and oil-in-water nanoemulsions
US13/845,515 Division US9884299B2 (en) 2006-03-31 2013-03-18 Process for the preparation of water-in-oil and oil-in-water nanoemulsions

Publications (2)

Publication Number Publication Date
WO2007112967A1 true WO2007112967A1 (en) 2007-10-11
WO2007112967A8 WO2007112967A8 (en) 2008-10-23

Family

ID=37243014

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/EP2007/002863 Ceased WO2007112967A1 (en) 2006-03-31 2007-03-28 Process for the preparation of water-in-oil and oil-in-water nanoemulsions

Country Status (14)

Country Link
US (2) US8431620B2 (en)
EP (1) EP2001981B1 (en)
JP (1) JP5694659B2 (en)
KR (1) KR101411754B1 (en)
CN (1) CN101443436B (en)
CA (1) CA2646175C (en)
CY (1) CY1124094T1 (en)
ES (1) ES2781798T3 (en)
IL (1) IL194255A (en)
IT (1) ITMI20060618A1 (en)
NO (1) NO345201B1 (en)
RU (1) RU2422192C2 (en)
SA (1) SA07280148B1 (en)
WO (1) WO2007112967A1 (en)

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2010067035A1 (en) * 2008-12-12 2010-06-17 Universite Lille 2 Droit Et Sante Method for making a formulation and use thereof for administering polar drugs
CN101423752B (en) * 2008-12-17 2010-12-29 山东大学 Lubricant for drilling fluids and preparation method thereof
WO2011033354A1 (en) 2009-09-18 2011-03-24 Eni S.P.A. Process for the recovery of oils from a solid matrix
WO2011048459A1 (en) 2009-10-20 2011-04-28 Eni S.P.A. Process for the recovery of heavy oil from an underground reservoir
ITMI20100695A1 (en) * 2010-04-23 2011-10-24 Eni Spa PROCEDURE FOR THE REMOVAL OF DEPOSITS FROM A WELL TO OIL OR GAS, AND / OR FROM SURFACE STRUCTURES, AND / OR FROM THE EQUIPMENT RELATED TO IT, AND / OR FROM FORMATIONS CONTAINING HYDROCARBONS
WO2012050984A1 (en) * 2010-10-13 2012-04-19 National Oilwell Varco, L.P. Releasable corrosion inhibitors
WO2012090153A1 (en) 2010-12-27 2012-07-05 Eni S.P.A. Method for limiting the water or gas coning in an extraction well of a hydrocarbon fluid
GB2487602A (en) * 2011-01-20 2012-08-01 James Heighway Diesel-water emulsions for improved engine operation
CN102728252A (en) * 2011-04-02 2012-10-17 中国石油化工股份有限公司 Method for preparing multiple emulsions from layered active particles
US8357639B2 (en) 2007-07-03 2013-01-22 Baker Hughes Incorporated Nanoemulsions
EP2612898A4 (en) * 2010-08-31 2014-06-25 Univ Tokyo WATER / OIL NANOEMULSION AND METHOD FOR PRODUCING THE SAME
WO2020128543A1 (en) * 2018-12-18 2020-06-25 Mol Magyar Olaj- És Gázipari Nyilvánosan Működő Részvénytársaság Kinetically stable nanoemulsions, processes for the preparation thereof and their use in petroleum and natural gas storage reservoirs, and in thermal water storage reservoirs, in well base treatment and bed stimulation processes
US10704003B2 (en) 2015-11-06 2020-07-07 Quadrise International Limited Oil-in-water emulsions
US10800892B2 (en) 2017-12-13 2020-10-13 China University Of Petroleum-Beijing Composition of nano-emulsion having small particle size and ultra-low concentration and a preparation method thereof

Families Citing this family (59)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9222013B1 (en) 2008-11-13 2015-12-29 Cesi Chemical, Inc. Water-in-oil microemulsions for oilfield applications
FR2954107B1 (en) * 2009-12-23 2012-04-20 Oreal COSMETIC COMPOSITION IN THE FORM OF NANOEMULSION CONTAINING VOLATILE LINEAR ALKANE
EP2691496A2 (en) 2011-03-29 2014-02-05 Fuelina, Inc. Hybrid fuel and method of making the same
FR2979632B1 (en) * 2011-09-05 2014-06-27 Ceca Sa DI-FUNCTIONAL ADDITIVES ANTI-DEPOSITS AND ANTI-CORROSION
US20130292121A1 (en) 2012-04-15 2013-11-07 Cesi Chemical, Inc. Surfactant formulations for foam flooding
US11407930B2 (en) 2012-05-08 2022-08-09 Flotek Chemistry, Llc Compositions and methods for enhancement of production of liquid and gaseous hydrocarbons
US9200192B2 (en) 2012-05-08 2015-12-01 Cesi Chemical, Inc. Compositions and methods for enhancement of production of liquid and gaseous hydrocarbons
CN102755847B (en) * 2012-07-17 2014-08-06 山东大学 Preparation method of water-in-oil nano-emulsion with low energy consumption
PL400489A1 (en) * 2012-08-23 2014-03-03 Glob Investment Spólka Z Ograniczona Odpowiedzialnoscia Method for producing fuel and the fuel
PL400488A1 (en) * 2012-08-23 2014-03-03 Glob Investment Spólka Z Ograniczona Odpowiedzialnoscia Method for producing fuel and the fuel
WO2014117236A1 (en) * 2013-01-30 2014-08-07 Universidade Federal Do Rio De Janeiro - Ufrj Oil-in-water nanoemulsion and process for producing same
US9464223B2 (en) 2013-03-14 2016-10-11 Flotek Chemistry, Llc Methods and compositions for use in oil and/or gas wells
US9868893B2 (en) 2013-03-14 2018-01-16 Flotek Chemistry, Llc Methods and compositions for use in oil and/or gas wells
US10717919B2 (en) 2013-03-14 2020-07-21 Flotek Chemistry, Llc Methods and compositions for use in oil and/or gas wells
US10421707B2 (en) 2013-03-14 2019-09-24 Flotek Chemistry, Llc Methods and compositions incorporating alkyl polyglycoside surfactant for use in oil and/or gas wells
US10000693B2 (en) 2013-03-14 2018-06-19 Flotek Chemistry, Llc Methods and compositions for use in oil and/or gas wells
US9884988B2 (en) 2013-03-14 2018-02-06 Flotek Chemistry, Llc Methods and compositions for use in oil and/or gas wells
US10590332B2 (en) 2013-03-14 2020-03-17 Flotek Chemistry, Llc Siloxane surfactant additives for oil and gas applications
US10941106B2 (en) 2013-03-14 2021-03-09 Flotek Chemistry, Llc Methods and compositions incorporating alkyl polyglycoside surfactant for use in oil and/or gas wells
US10287483B2 (en) 2013-03-14 2019-05-14 Flotek Chemistry, Llc Methods and compositions for use in oil and/or gas wells comprising a terpene alcohol
US9428683B2 (en) 2013-03-14 2016-08-30 Flotek Chemistry, Llc Methods and compositions for stimulating the production of hydrocarbons from subterranean formations
US11254856B2 (en) 2013-03-14 2022-02-22 Flotek Chemistry, Llc Methods and compositions for use in oil and/or gas wells
US10577531B2 (en) 2013-03-14 2020-03-03 Flotek Chemistry, Llc Polymers and emulsions for use in oil and/or gas wells
US9321955B2 (en) 2013-06-14 2016-04-26 Flotek Chemistry, Llc Methods and compositions for stimulating the production of hydrocarbons from subterranean formations
US10053619B2 (en) 2013-03-14 2018-08-21 Flotek Chemistry, Llc Siloxane surfactant additives for oil and gas applications
US11180690B2 (en) 2013-03-14 2021-11-23 Flotek Chemistry, Llc Diluted microemulsions with low surface tensions
US9068108B2 (en) 2013-03-14 2015-06-30 Cesi Chemical, Inc. Methods and compositions for stimulating the production of hydrocarbons from subterranean formations
US10556210B2 (en) * 2014-02-24 2020-02-11 Statoil Petroleum As Prevention of surge wave instabilities in three phase gas condensate flowlines
US9890624B2 (en) 2014-02-28 2018-02-13 Eclipse Ior Services, Llc Systems and methods for the treatment of oil and/or gas wells with a polymeric material
US9890625B2 (en) 2014-02-28 2018-02-13 Eclipse Ior Services, Llc Systems and methods for the treatment of oil and/or gas wells with an obstruction material
US9505970B2 (en) 2014-05-14 2016-11-29 Flotek Chemistry, Llc Methods and compositions for use in oil and/or gas wells
US9957779B2 (en) 2014-07-28 2018-05-01 Flotek Chemistry, Llc Methods and compositions related to gelled layers in oil and/or gas wells
EP3218452B1 (en) * 2014-11-10 2019-07-31 EME Finance Ltd Water in diesel oil fuel micro-emulsions.
WO2016074903A1 (en) 2014-11-10 2016-05-19 Eme International Limited Device for mixing water and diesel oil, apparatus and process for producing a water/diesel oil micro-emulsion.
EP3227411B1 (en) 2014-12-03 2019-09-04 Drexel University Direct incorporation of natural gas into hydrocarbon liquid fuels
CN104667772B (en) * 2015-01-30 2016-11-23 山东大学 A kind of heat-resistant salt-resistant water-in-oil nano-emulsion and preparation method thereof
WO2016156584A1 (en) 2015-04-03 2016-10-06 Versalis S.P.A. Mixture of solvents for removing asphaltenes
CN106609135A (en) * 2015-10-26 2017-05-03 中国石油化工股份有限公司 Salt-resistant nano-emulsion injection enhancement agent for oilfield water injection and preparation method thereof
CN105566923B (en) * 2015-12-10 2017-09-12 中国石油大学(华东) A kind of viscoplasticity nanoemulsions and preparation method thereof
CN105771714A (en) * 2016-04-22 2016-07-20 东南大学 Preparation method of water-in-oil type nanometer emulsion
US20190242229A1 (en) * 2016-11-21 2019-08-08 Multi-Chem Group Llc Nanoemulsions for use in subterranean fracturing treatments
IT201600132801A1 (en) 2016-12-30 2018-06-30 Eme International Ltd Apparatus and process for producing liquid from biomass, biofuel and biomaterial
US10934472B2 (en) 2017-08-18 2021-03-02 Flotek Chemistry, Llc Compositions comprising non-halogenated solvents for use in oil and/or gas wells and related methods
US11219581B2 (en) 2017-10-10 2022-01-11 Conopco, Inc. Nanoemulsions with neutralized fatty acid and a method producing the same
WO2019108971A1 (en) 2017-12-01 2019-06-06 Flotek Chemistry, Llc Methods and compositions for stimulating the production of hydrocarbons from subterranean formations
WO2019224048A1 (en) 2018-05-23 2019-11-28 Unilever Plc Nanoemulsions and a method for making the same
US11111426B2 (en) 2018-05-30 2021-09-07 Saudi Arabian Oil Company In-situ salinity adjustment to improve waterflooding performance in oil-wet carbonate reservoirs
US11807832B2 (en) 2018-06-05 2023-11-07 Kao Corporation Liquid detergent composition for tableware and/or kitchen hard articles
KR102120846B1 (en) * 2018-09-06 2020-06-09 김성오 Eco-friendly slime removing agent for cooling system
US12466989B2 (en) * 2018-09-14 2025-11-11 Petroliam Nasional Berhad (Petronas) Microemulsions and uses thereof
CN110003873A (en) * 2019-04-16 2019-07-12 济南大学 A kind of preparation method of neutral homogeneous self-heating double-effect unblocking and descaling agent
CN110003874A (en) * 2019-04-16 2019-07-12 济南大学 A kind of preparation method of temperature-controlled double-effect deblocking and descaling agent
US11104843B2 (en) 2019-10-10 2021-08-31 Flotek Chemistry, Llc Well treatment compositions and methods comprising certain microemulsions and certain clay control additives exhibiting synergistic effect of enhancing clay swelling protection and persistency
KR102560024B1 (en) * 2019-11-07 2023-07-26 한국과학기술원 Method of Gas Hydrate Inhibition Using Recoverable Magnetic Nanoparticles
KR102338273B1 (en) 2020-06-11 2021-12-14 한국전력공사 Magnetic support penetrated type spacer for gas insulated switchgear structure
US11512243B2 (en) 2020-10-23 2022-11-29 Flotek Chemistry, Llc Microemulsions comprising an alkyl propoxylated sulfate surfactant, and related methods
CN112335650B (en) * 2020-11-06 2021-07-13 中国农业大学 A kind of soluble agent and preparation method thereof
CN113563861B (en) * 2021-07-27 2022-12-23 中国石油大学(北京) A kind of microemulsion composition, nanoemulsion and its preparation method and application, fracturing fluid
KR102661960B1 (en) * 2023-09-07 2024-04-29 주식회사 뉴앤뉴 Method for preparing low-energy nanoemulsions

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1998018884A2 (en) * 1996-10-28 1998-05-07 Massachusetts Institute Of Technology Nanostructured aqueous fuels
EP1172077A1 (en) * 2000-07-13 2002-01-16 L'oreal Nanoemulsion containing nonionic polymers

Family Cites Families (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR0148748B1 (en) * 1988-09-16 1998-08-17 장 크라메르, 한스 루돌프 하우스 Pharmaceutical composition containing cyclosporin
ATE144137T1 (en) * 1991-07-26 1996-11-15 Smithkline Beecham Corp W/O MICROEMULSIONS
JPH08505367A (en) * 1992-10-16 1996-06-11 スミスクライン・ビーチャム・コーポレイション Pharmaceutical emulsion composition
FR2709666B1 (en) * 1993-09-07 1995-10-13 Oreal Cosmetic or dermatological composition consisting of an oil-in-water emulsion based on oily globules provided with a lamellar liquid crystal coating.
US5792223A (en) * 1997-03-21 1998-08-11 Intevep, S.A. Natural surfactant with amines and ethoxylated alcohol
JP4318332B2 (en) * 1998-12-24 2009-08-19 ライオン株式会社 Method for producing emulsified liquid composition
FR2804016B1 (en) * 2000-01-21 2006-07-28 Oreal NANEMULSION CONTAINING AMPHIPHILIC LIPIDS AND PEG ESTER AND USES THEREOF
FR2809010B1 (en) * 2000-05-22 2002-07-12 Oreal NANOEMULSION BASED ON ANIONIC POLYMERS, AND ITS USES IN PARTICULAR IN THE COSMETIC, DERMATOLOGICAL, PHARMACEUTICAL AND / OR OPHTHALMOLOGICAL FIELDS
IT1318539B1 (en) * 2000-05-26 2003-08-27 Italfarmaco Spa PROLONGED RELEASE PHARMACEUTICAL COMPOSITIONS FOR THE PARENTERAL ADMINISTRATION OF BIOLOGICALLY HYDROPHILE SUBSTANCES
US20020155084A1 (en) * 2000-06-02 2002-10-24 The Regents Of The University Of The Michigan Nanoemulsion formulations
JP3919449B2 (en) * 2001-02-09 2007-05-23 株式会社ジャパンエナジー W / O emulsion type flame retardant hydraulic fluid
CN1709561B (en) * 2004-06-17 2010-09-08 海茂株式会社 Water-in-oil emulsion and method for producing its diluent
GB2434372A (en) 2006-01-20 2007-07-25 Palox Offshore S A L Water-in-oil microemulsions

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1998018884A2 (en) * 1996-10-28 1998-05-07 Massachusetts Institute Of Technology Nanostructured aqueous fuels
EP1172077A1 (en) * 2000-07-13 2002-01-16 L'oreal Nanoemulsion containing nonionic polymers

Cited By (27)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8822385B2 (en) 2007-07-03 2014-09-02 Baker Hughes Incorporated Nanoemulsions
US8357639B2 (en) 2007-07-03 2013-01-22 Baker Hughes Incorporated Nanoemulsions
FR2939698A1 (en) * 2008-12-12 2010-06-18 Univ Lille Ii Droit & Sante PROCESS FOR PRODUCING FORMULATION AND USE FOR THE DELIVERY OF POLAR MEDICINAL PRODUCTS
WO2010067035A1 (en) * 2008-12-12 2010-06-17 Universite Lille 2 Droit Et Sante Method for making a formulation and use thereof for administering polar drugs
CN101423752B (en) * 2008-12-17 2010-12-29 山东大学 Lubricant for drilling fluids and preparation method thereof
US20120199517A1 (en) * 2009-09-18 2012-08-09 Eni S.P.A. Process for the recovery of oils from a solid matrix
WO2011033354A1 (en) 2009-09-18 2011-03-24 Eni S.P.A. Process for the recovery of oils from a solid matrix
WO2011048459A1 (en) 2009-10-20 2011-04-28 Eni S.P.A. Process for the recovery of heavy oil from an underground reservoir
US9951263B2 (en) * 2009-10-20 2018-04-24 Eni S.P.A. Process for the recovery of heavy oil from an underground reservoir
US20120261120A1 (en) * 2009-10-20 2012-10-18 Eni S.P.A. Process for the recovery of heavy oil from an underground reservoir
WO2011132052A1 (en) 2010-04-23 2011-10-27 Eni S.P.A. Process for the removal of deposits from an oil or gas well, and/or from the surface structures, and/or from the equipment connected therewith, and/or from hydrocarbon bearing formations
ITMI20100695A1 (en) * 2010-04-23 2011-10-24 Eni Spa PROCEDURE FOR THE REMOVAL OF DEPOSITS FROM A WELL TO OIL OR GAS, AND / OR FROM SURFACE STRUCTURES, AND / OR FROM THE EQUIPMENT RELATED TO IT, AND / OR FROM FORMATIONS CONTAINING HYDROCARBONS
US9845424B2 (en) 2010-04-23 2017-12-19 Eni S.P.A. Process for the removal of deposits from an oil or gas well, and/or from the surface structures, and/or from the equipment connected therewith, and/or from hydrocarbon bearing formations
EP2612898A4 (en) * 2010-08-31 2014-06-25 Univ Tokyo WATER / OIL NANOEMULSION AND METHOD FOR PRODUCING THE SAME
GB2498145A (en) * 2010-10-13 2013-07-03 Nat Oilwell Varco Lp Releasable corrosion inhibitors
CN103210120A (en) * 2010-10-13 2013-07-17 国民油井华高有限公司 Releasable corrosion inhibitors
US8383559B2 (en) 2010-10-13 2013-02-26 National Oilwell Varco, L.P. Releasable corrosion inhibitors
WO2012050984A1 (en) * 2010-10-13 2012-04-19 National Oilwell Varco, L.P. Releasable corrosion inhibitors
CN103210120B (en) * 2010-10-13 2015-09-09 国民油井华高有限公司 Releasable Corrosion Inhibitors
GB2498145B (en) * 2010-10-13 2017-08-30 Nat Oilwell Varco Lp Releasable corrosion inhibitors
WO2012090153A1 (en) 2010-12-27 2012-07-05 Eni S.P.A. Method for limiting the water or gas coning in an extraction well of a hydrocarbon fluid
GB2487602A (en) * 2011-01-20 2012-08-01 James Heighway Diesel-water emulsions for improved engine operation
CN102728252A (en) * 2011-04-02 2012-10-17 中国石油化工股份有限公司 Method for preparing multiple emulsions from layered active particles
CN102728252B (en) * 2011-04-02 2014-04-16 中国石油化工股份有限公司 Method for preparing multiple emulsions from layered active particles
US10704003B2 (en) 2015-11-06 2020-07-07 Quadrise International Limited Oil-in-water emulsions
US10800892B2 (en) 2017-12-13 2020-10-13 China University Of Petroleum-Beijing Composition of nano-emulsion having small particle size and ultra-low concentration and a preparation method thereof
WO2020128543A1 (en) * 2018-12-18 2020-06-25 Mol Magyar Olaj- És Gázipari Nyilvánosan Működő Részvénytársaság Kinetically stable nanoemulsions, processes for the preparation thereof and their use in petroleum and natural gas storage reservoirs, and in thermal water storage reservoirs, in well base treatment and bed stimulation processes

Also Published As

Publication number Publication date
NO345201B1 (en) 2020-11-02
RU2008140070A (en) 2010-05-10
US20130209527A1 (en) 2013-08-15
JP5694659B2 (en) 2015-04-01
SA07280148B1 (en) 2012-09-12
KR20090007383A (en) 2009-01-16
CN101443436A (en) 2009-05-27
KR101411754B1 (en) 2014-06-25
IL194255A (en) 2013-08-29
US8431620B2 (en) 2013-04-30
CA2646175A1 (en) 2007-10-11
NO20084312L (en) 2009-01-02
RU2422192C2 (en) 2011-06-27
US20090118380A1 (en) 2009-05-07
EP2001981B1 (en) 2020-01-15
JP2009538221A (en) 2009-11-05
CN101443436B (en) 2013-01-09
ES2781798T3 (en) 2020-09-07
CY1124094T1 (en) 2022-03-24
ITMI20060618A1 (en) 2007-10-01
EP2001981A1 (en) 2008-12-17
WO2007112967A8 (en) 2008-10-23
CA2646175C (en) 2014-12-02
US9884299B2 (en) 2018-02-06

Similar Documents

Publication Publication Date Title
US8431620B2 (en) Process for the preparation of water-in-oil and oil-in-water nanoemulsions
Kumar et al. Thermodynamic and physicochemical properties evaluation for formation and characterization of oil-in-water nanoemulsion
US9366387B2 (en) Process of preparing improved heavy and extra heavy crude oil emulsions by use of biosurfactants in water and product thereof
Bai et al. Formation and stabilization of nanoemulsions using biosurfactants: Rhamnolipids
Gazolu-Rusanova et al. Food grade nanoemulsions preparation by rotor-stator homogenization
Pons et al. Formation and properties of miniemulsions formed by microemulsions dilution
JP3042999B2 (en) Multi-phase emulsion and method for producing the same
CA2708440C (en) Emulsification dispersants, a method for emulsification and dispersion using the emulsification dispersants, emulsions, and emulsion fuels
Nazar et al. Surface active ionic liquid and Tween-80 blend as an effective dispersant for crude oil spill remediation
GB2503564A (en) Foam control formulations
MXPA05002817A (en) Fiber assisted emulsion system.
EP0130891A1 (en) Biopolymer compositions and process for their preparation
Sattarpour et al. Effect of pH on the stability of water in heavy crude oil emulsions stabilized by saponin and rhamnolipid biosurfactants
WO2020128543A1 (en) Kinetically stable nanoemulsions, processes for the preparation thereof and their use in petroleum and natural gas storage reservoirs, and in thermal water storage reservoirs, in well base treatment and bed stimulation processes
CN115428934B (en) A bicontinuous emulsion used in the food and pharmaceutical fields and its preparation method
RU2184222C2 (en) Hydrocarbon gel based on iron salts of organic orthophosphoric esters
Zhang et al. Olive oil-in-water high internal phase Pickering emulsions stabilized by hydroxyapatite nanoparticles
Jiang et al. Physicochemical characterization of nonionic surfactants in oil-in-water (O/W) nano-emulsions for new pesticide formulations
CN107913641A (en) A kind of preparation method of microemulsion
JP2007074909A (en) Edible emulsion and method for producing the same
Bullón Formulation in Surfactant Systems: From-Winsor-to-HLDN
Solovyev et al. The correlation between the surface-active characteristics of SAFOL 23-alcohol-water systems and the length of the alkyl radical of the alcohol
Forgiarini Formulation in Surfactant Systems: From-Winsor-to-HLDN
Board Emulsion Properties of Mixed Tween20-Span20 in Non-Aqueous System

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 07723805

Country of ref document: EP

Kind code of ref document: A1

WWE Wipo information: entry into national phase

Ref document number: 2646175

Country of ref document: CA

Ref document number: 2007723805

Country of ref document: EP

WWE Wipo information: entry into national phase

Ref document number: 194255

Country of ref document: IL

WWE Wipo information: entry into national phase

Ref document number: 2009501962

Country of ref document: JP

NENP Non-entry into the national phase

Ref country code: DE

WWE Wipo information: entry into national phase

Ref document number: 5632/CHENP/2008

Country of ref document: IN

ENP Entry into the national phase

Ref document number: 2008140070

Country of ref document: RU

Kind code of ref document: A

WWE Wipo information: entry into national phase

Ref document number: 1020087026798

Country of ref document: KR

Ref document number: A20081265

Country of ref document: BY

WWE Wipo information: entry into national phase

Ref document number: 200780016432.X

Country of ref document: CN

WWE Wipo information: entry into national phase

Ref document number: 12294552

Country of ref document: US