Nehal S. Ahmed

Formation of fluid heavy oil-in-water emulsions for pipeline transportation

Abstract The diverse factors affecting the viscosity of a surfactant stabilized viscous crude oil-in-water emulsion for pipeline transportation were studied. The study discloses that the stability of the oil-in-water emulsion stabilized by a nonionic surfactant Nonyl Phenol Ethoxylate increases as the surfactant concentration increases with a subsequent decrease in the crude-oil–water interfacial tension (IFT). Increasing the oil content and the speed of mixing of the emulsion resulted in an increased emulsion stability. Fresh water and synthetic formation water were used to study the effect of aqueous phase salinity on the stability and viscosity of the emulsion. Surfactant dissolved in synthetic formation water was utilized to find out the possibility of injecting the surfactant into a well bore to effect emulsification in the pump or tubing for the production of heavy crude oils as oil-in-water emulsion. The effective viscosity of a viscous Egyptian crude oil (Geisum crude oil) decreased when it was emulsified with water in the presence of a nonionic surfactant in the form of an oil-in-water emulsion. It was possible to form stable emulsions with synthetic formation water characterized by a low dynamic shear viscosity. This will enhance the production of viscous crude oils by injecting surfactant dissolved in formation water to affect downhole emulsification. Further, the produced crude oil-in-water emulsion is characterized by its low effective viscosity which will facilitate its pipeline transportation to the refiner.

STABILITY AND RHEOLOGY OF HEAVY CRUDE OIL-IN-WATER EMULSION STABILIZED BY AN ANIONIC- NONIONIC SURFACTANT MIXTURE

ABSTRACT The stability and rheology of an Egyptian Heavy crude oil-in-water emulsions stabilized by an anionic (TDS) and a nonionic (NPE) surfactants individually or in a mixture have been studied. The study reveals that, the viscosity of the crude oil decreases when it is emulsified with water in the form of an oil-in-water type of emulsion. The stability of the oil-in-water emulsion increases as the surfactant concentration and speed of mixing of the emulsion increases. Fresh water and synthetic formation water have been used to study the effect of aqueous phase salinity on the stability and viscosity of the emulsion. Surfactant dissolved in synthetic formation water has been utilized to find out the possibility of injecting the surfactant into a well bore to effect emulsification in the pump or tubing for enhancing the production of heavy crude oils as oil-in-water emulsion. The study revealed that, the viscosity of the emulsion containing fresh water is always less than that containing formation water...

Multifunctional Additives Viscosity Index Improvers, Pour Point Depressants and Dispersants for Lube Oil

Abstract In the present work, some polymeric additives based on styrene-maleic anhydride copolymer were prepared and evaluated as multifunction lube oil additives (viscosity index improvers, pour point depressants, and detergent-dispersant additives). The styrene-maleic anhydride copolymer reacted with different alcohols (dodecyl alcohol, hexadecyl alcohol, octadecyl alcohol, and docosanol) to prepare four different types of esters and aminated with different types of amines (dodecyl amine, hexadecyl amine, and octadecyl amine) to prepare another three co-polymeric additives. Structure of the prepared compounds was confirmed by I.R. spectroscopy. The molecular weights of the prepared copolymers were determined by using gel permeation chromatograph and the percentage of esterification and amination were determined by 1HNMR. The efficiencies of the prepared compounds as viscosity index improvers, pour point depressants, and detergents-dispersants were investigated. It was found that the efficiency of the prepared compound as viscosity index improvers increases with increasing the concentration of additives in the solution and with increasing the molecular weight of prepared compounds, while the efficiency of the prepared compounds as pour point depressants increases with decreasing the concentration of the prepared polymers. On the other hand, the prepared compounds showed excellent dispersion power.

Preparation and Evaluation of Acrylate Polymers as Viscosity Index Improvers for Lube Oil

Abstract This work is confined to the preparation and characterization of acrylate polymeric additives. These additives were prepared by esterification of acrylic acid with different alcohols (decyl, 1-dodecyl, 1-tetradecyl, and hexadecyl) and then copolymerization of the prepared esters with different moles of styrene. The molecular weights of the prepared copolymers were determined by GPC. The efficiency of the prepared copolymers for improving the viscosity index of the lube oil was studied. It was found that the efficiency increases with increasing the molecular weight of the prepared copolymers.

Synthesis and evaluation of some polymeric surfactants for treating crude oil emulsions. Part I: treatment of sandy soil polluted with crude oil by monomeric and polymeric surfactants

Abstract In the present work, five surfactants were prepared; two of them were monomeric surfactants, one was anionic (tri-ethanol ammonium salt of dodecyl benzene sulfonic acid, E1) and the second was non-ionic surfactant (nonyl phenol ethoxylate,E2). The other three surfactants were polymeric non-ionic surfactants (ethoxylated polynonyl phenol formaldehyde mono-ethanol amine E3, ethoxylated poly nonyl phenol formaldehyde diethanol amine E4, and ethoxylated nonoyl phenol formaldehyde triethanol amine E5). The gel permeation chromatography (GPC) and the elemental analysis were carried out to determine the molecular weight of the polymeric surfactants. The surface properties for these surfactants were determined by measuring the surface tension, the interfacial tension, the foaming power, cloud point and the emulsification power. The polymeric surfactants were used to treat the polluted sandy soil, which saturated with two types of crude oils (waxy and asphaltenic). From the data obtained it was found that, the increasing of surfactant concentrations led to increase the reclaimation of the waxy and asphaltinic crude oil percentages and decreased the interfacial tension. The reclaimed oil percentage increased with decreasing the hydrophilic-lipophilic balance (HLB) value of non-ionic surfactant. In general behavior, the reclamation of the asphaltenic crude oil was greater than the reclaimation of the waxy crude oil. The data were discussed on light of the chemical structure of the surfactants and composition of crude oil.

Synthesis and Evaluation of Some Polymeric Compounds as Pour Point Depressants and Viscosity Index Improvers for Lube Oil

Abstract In the present study, some polymeric additives were prepared and used as pour point depressants and as viscosity index improvers for lube oil via copolymerization of maleic anhydride and vinyl acetate with different esters of acrylic acid. The molecular weights of the prepared copolymers were determined by GPC. The efficiency of the prepared compounds as pour point depressant and viscosity index improvers was investigated. It was found that the efficiency of the prepared compounds as pour point depressant increases with decreasing the concentration of the prepared polymers, increasing the chain length of alkyl groups, and increases with decreasing the molecular weight. The efficiency of the prepared compounds as viscosity index improvers increases by increasing the concentration of these additives and by increasing the molecular weight of the polymer.

SODIUM LIGNIN SULFONATE TO STABILIZE HEAVY CRUDE OIL-IN-WATER EMULSIONS FOR PIPELINE TRANSPORTATION

ABSTRACT The efficiency of sodium lignin sulfonate (SLS) as an anionic surfactant derived from waste wood pulping industry in stabilizing an Egyptian heavy crude oil (Geisum)-in-water emulsions for pipeline transportation has been investigated. The stability and rheology of the emulsions stabilized by SLS or with a nonionic surfactant nonyl phenol diethylenetriamine formaldehyde ethoxylate (NDFE) individually or in a mixture have been studied. It has been found that the dynamic shear viscosity of the crude oil decreases substantially when it is emulsified with water in the form of an oil-in-water type of emulsion. The stability of the oil-in-water emulsion increases as the surfactant concentration increases. Potable water and saline water containing different molar concentrations of NaCI have been used to study the effect of aqueous phase salinity on the stability and viscosity of the emulsion. Surfactant dissolved in saline water has been utilized to find out the possibility of injecting the surfactant into a well bore to effect emulsification in the pump or tubing for enhancing the production of heavy crude oils as oil-in-water emulsion. The study revealed that, the viscosity of the emulsion containing potable water is always less than that containing saline water and the viscosity increases as the salt content increased.

Synthesis and Properties of Nonionic Surfactants from Rosin-Imides Maleic Anhydride Adduct

Ester-adduct derivatives of rosin were synthesized by reacting rosin with polyethylene glycol 600 (PEG 600) or 2000 (PEG2000) and maleic anhydride (MA) at elevated temperature. These derivatives were evaluated for acid number, FTIR spectroscopy, molecular weight (Mw), and polydispersity. The derivatives were soluble in organic solvents; aqueous solubility was pH dependent. Rosin-imides were synthesized from a rosin ester-maleic anhydride adducts. It was condensed with diaminobutane or triethylene tetramine to obtain rosinimides. This imide was etherified by reaction with PEG in the presence of β,β′-dichlorodiethyl ether as a linking agent and NaOH as a catalyst. The surface properties of the prepared surfactants were determined by measuring the surface tension at different temperatures. The surface tension, critical micelle concentration and surface activities were determined at different temperatures. Surface parameters such as surface excess concentration (Γmax), the area per molecule at interface (Amin), and the effectiveness of surface tension reduction (πCMC) were determined from the adsorption isotherms of the prepared surfactants. Some thermodynamic data for the adsorption process were calculated and are discussed.

Synthesis and evaluation of detergent/dispersant additives from polyisobutylene succinimides

Lube oil additives are essential for all types of lubricating oils; they are added either to give the oils new properties as detergency and oxidation stability or to improve such properties as pour point and viscosity index. They are added at varying proportions to meet the performance requirements. The present work is concerned with studying of detergent/dispersant type additives based on synthesized polyisobutylene succinic anhydride (PIBSA) and its aminated compounds (PIBSA) with different types of polyethylene polyamine such as ethylene diamine, diethylene Triamine, Triethylene tetramine, and tetraethylene pentamine. Different types of polyisobutylene succinimides were reacted with dodecylphenol and formaldehyde to prepare different type of Mannish bases. The efficiency of the prepared compounds as antioxidants and detergents/dispersants was investigated. It was found that compound D1 (Mannich base IV) is the best antioxidant additive for lube oil, and all the prepared compounds have excellent dispersancy power.

Multifunctional Lube Oil Additives Based on Octadecene-Maleic Anhydride Copolymer

Abstract In the present work, some polymeric additives based on octadecene-maleic anhydride copolymer were prepared and evaluated as multifunctional lube oil additives (viscosity index improvers, pour point depressants, and detergent/dispersant additives). The octadecene-maleic anhydride copolymer reacted with different alcohols (dodecyl, hexadecyl, octadecyl, and docosanol) to prepare four different types of esters then were aminated with different types of amines (dodecyl, hexadecyl, and octadecyl) to prepare another three copolymeric additives. Structures of the prepared compounds were confirmed by infrared (IR) spectroscopy and determination of molecular weight was made using gel permeation chromatography (GPC). The percentage of esterification and amination were determined by 1HNMR. The efficiencies of the prepared compounds as viscosity index improvers, pour point depressants, and detergents/dispersants were investigated. It was found that the efficiency of the prepared compound as viscosity index improvers increases with increasing the concentration of additives and with increasing the alkyl chain length of prepared compounds, whereas the efficiency of the prepared compounds as pour point depressants increases with decreasing the concentration of the prepared polymers. On the other hand, the prepared compounds showed excellent dispersion power.