Crude wetting properties

The matrices obtained are adherent and comparable to those prepared from B(NHCH3)3.7 However, since (4) can be considered to be a derivative of B(NHPri)3, their interest as BN films precursors may be compared. Thus, after the impregnation of carbon fibres by crude B(NHPr )3, an ammonia treatment was required in order to reduce the volatility of the precursor before pyrolysis. B(NHPr )3, which is stable with respect to autopolymerisation, reacts spontaneously with NH3 leading to a polyborazine with a low carbon content. The BN matrices obtained are not dense and the fibres are not totally embedded, indicating a lack of adherence of the BN matrix onto the fibres. This result could be related to the low hydrocarbon chain ratio of the polyborazine derived from B(NHPr )3, which shorten drastically its carbon wetting properties. 

Capillary sealing effects are controlled by wetting phenomena which, for hydrocarbons in general, are poorly constrained. In real sub-surface situations, the assumption of a water-wet seal is reasonable for an initially hydrocarbon-free seal. This may be less likely in dynamic situations where capillary seals may leak periodically in the presence of active charge. The wetting properties of seals may change through time an initially water-wet seal may evolve into a hydrocarbon-wet seal, due to the adsorption of a variety of compounds from crude oil, such as asphaltenes (Anderson, 1986). This may ultimately result in a top seal which has no capillary seal capacity and leaks via two-phase flow. 

ST Dubey, PH Doe. Base numbers and wetting properties of crude oil. Proceedings of 66th Annual Technical Conference... 

The rheological characteristics of the crude oil/water interface arise from adsorption of crude oil surfactants at that interface. These surfactants are amphoteric and their adsorption at the liquid/liquid interface depends markedly on the properties of the aqueous phase. Attempts to produce model crude oil surfactants (4) showed that though the surface wetting properties of crude oils could be produced, the emulsion forming characteristics could not. We have therefore chosen to examine real crude oil/water interfaces in spite of the difficulties in interpretation that this sometimes entails ... 

Efiect of the Interaction Between Heavy Crude Oil Components and Stabilizing Solids with Different Wetting Properties... 

Adsorption studies performed with the QCM-D technique showed multilayer or aggregate formation of asphaltenes at the silica surface. Asphaltenes were irreversibly adsorbed as a rigid film. Visual inspection of the resin-coated silica particles clearly showed that the initially hydrophilic silica (Aerosil 200 and Aerosil 7200) adsorbed considerably more resins than the hydrophobic silica (Aerosil 972). By analyzing the toluene solutions for remaining asphaltenes with near-infrared (NIR) spectroscopy, they could conclude that the initially hydrophilic particles had adsorbed considerably more asphaltenes than the hydrophobic particles. All the products exhibited less adsorption of resins than of asphaltenes and the influence of their adsorption was dramatic, especially on the wettability of the hydrophilic silica. Very hydrophilic particles like the unmodified 200 or very hydrophobic particles like the 972 preferred the water and oil phase, respectively. In contrast, the Aerosil 7200 seemed to be equally partitioned between the two phases, indicating intermediate wetting properties. Generally, the stabilization efficiency was enhanced by adsorption of crude oil components onto very hydrophilic or very hydrophobic silica. 

Although the capillary pressure curve cannot be predicted from the fundamental properties of the particulate bed, a crude estimate of the entry suction for wetting liquids is given by (N2)... 

The basic crude fish oils are exemplified by the quality details of Table 3. Ranges are given because these are specifications for crude oils, produced at the level of over a million tons per year. The first six properties are traditional wet chemistry assays and the American Oil Chemists Society (AOCS) Official and Tentative... 

Although rf-limoncnc is commonly analyzed by gas chromatography/mass spectroscopy (GC/MS), wet chemical analysis is still used for certain applications, particularly by the industries using citrus (/-limonene as a chemical starting material (e.g., for synthesis of adhesive resins). Values of some of the useful properties of crude (/-limonene are listed in Table 5.6. 

Petroleum reservoirs can exhibit the full range of wettabilities from water-wet to oil-wet (53). Adsorption of crude oil heavy ends modifies solid surface properties and is thought to change reservoir wettability toward more oil-wet. Surfactant adsorption on hydrophobic surfaces takes place by hydrophobic interactions between surfactant hydrocarbon chains and the solid surface (35, 54—58). At low surfactant concentrations, surfactant molecules are oriented parallel to the surface. As the surfactant concentration increases, hydrophobic interactions between surfactant hydrophobes become significant. The surfactant molecules become oriented vertically to the surface with the polar groups toward the aqueous phase. 

The displacement of liquids is strongly affected by surface properties of the system crude oil-water-rocks. With increases in temperature, surface properties of both the formation rocks and the formation liquids change. When water is injected into the formation, some of the surface-active substances of the crude dissolve in the water. This dissolution brings about a reduction in surface tension at the phase boundary. Selective wetting of the surfaces of capillary pores with water is also improved. The surface-acdve molecules of oil form a layer that is adsorbed on the surfaces of pore canals. When the temperature is increased, the thickness of this layer is reduced, which, in turn, leads to an increase in permeability of the formation. 

Alkaline flooding is based on the reaction that occurs between the alkaline water and the organic acids, naturally occurring in some crudes, to produce in-situ surfactants or emulsifying soaps at the oil/water interface. Recent literature (i-J.) summarizes several proposed mechanisms by which alkaline water-flooding will enhance oil recovery. These mechanisms include emulsification and entrapment, emulsification and entrainment, and wettability reversal (oil-wet to water-wet or water-wet to oil-wet). Depending on the initial reservoir and experimental conditions with respect to oil, rock and injection water properties, one or more of these proposed mechanisms may be controlling. 

Considering a global plastic production of 245 Mio mto (2006), petrochemical-based adhesives and sealants represent just 3% of this. Dry adhesive in this sense is the solid portion of an adhesive governing its overall performance properties, whereas wet adhesives describe the ready-to-use product in its average proportion of solid (34%) and liquid (66%) ingredients. The liquid phase commonly and increasingly is water, but 0.71 Mio dry mto (2006), respectively 0.78 Mio dry mto (2010), remain solvent- and thus crude-oil-based, a sizable factor that has to be regarded as well. 

Properties Liq. or flakes nonionic Uses Demulsifier for crude oil surfactant for household/industrial cleaners dispersant, thickener for paints, printing inks, cosmetics, rubber solubilizer, wetting agent for textile/paper auxs. 

In the context of petroleum technology, surface chemistry deals with the surface properties of crude oil/air, crude oil/brine (or water) and crude oil/solid surfaces. Thus, surface tension, interfacial tension (IFT), contact angle, wetting and surface charge (zeta potential) are the parameters that one measures for surface... 

The microscopic processes of crude oil displacement by immmis-cible surfactant solutions and, therefore, the efficiency of tertiary oil recovery are determined by static and dynamic wetting as well as by the stability of the liquid film adjacent to the solid surface. All these properties are connected also with the liquid/ liquid interfacial tension and the flow conditions. The two-liquid flow influences dynamic wetting via the shear force exerted on the liquid/liquid interface (1-5), and it affects also the film stability by those forces that act directly at the film of liquid jS/bulk liquid A boundary (6-7). 

Surfactants are widely used to control wetting, capillary penetration, and evaporation. Adsorption of surfactants accelerates mass transfer processes, such as impregnation of hydrophobic porous bodies by aqueous solutions, cleaning of greasy oiled surfaces, and crude oil recovery. Surface modification of adsorbents, membranes, and catalysts by surfactants is often used to control their properties. 

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