Alpha Olefin Sulphonate Research Articles

The Effect of Alpha Olefin Sulphonate (AOS) Surfactant Injection on Sandstone Rock on Increasing Oil Recovery with Variations in Salinity, Concentration, and Temperatures: A Laboratory Study

In this study, Alpha Olefin Sulphonate (AOS) surfactant was injected. This laboratory test aims to verify the correlation between a surfactant solution’s low IFT value and its ability to yield a high oil recovery value. The salinity used in this research was 5000 ppm and 15000 ppm. Then it was mixed with AOS surfactant at concentrations of 0.5%, 1%, and 2%. At the same time, the temperatures used are 30 °C and 60 °C. After testing, it was found that a solution with a salinity of 15,000 ppm and a surfactant concentration of 2% had the lowest IFT value and was proven to have a total RF of 73%.

Synergistic Combination of Carbohydrate Polymer with Conventional Active Materials for Detergent Formulations

Novel ecofriendly polymeric surfactant based on Sorbitol and Maleic anhydride has been synthesized and used successfully in detergent composition. Sorbitol is obtained majorly as a vegetable product. In present research work a small quantity of Maleic anhydride and Benzoic acid along with major quantity of Sorbitol has been used in synthesis of polymer. The mole ratio of ingredients and cooking schedule has been standardized to get desired molecular weight, HLB ratio and surfactant properties. Powder detergents have been formulated based on these novel polymer and conventional active ingredients such as alpha olefin sulphonate, sodium lauryl sulphate. And linear alkyl benzene sulphonate. This synergistic combination of novel polymer has been used as a 60 to 80% replacement of conventional linear alkyl benzene sulphonate in detergent powder formulation. The preparation of this polymer is ecofriendly and has a potential for commercial use as an ecofriendly detergent in powder form. The surface tension, foam height, % detergency and stain removing characteristics have been evaluated and compared with commercially available powder detergent sample. The petroleum resources are soaring in price and their replacement with novel polymer of vegetable origin will certainly promote the cause of Green Chemistry and Green Environment. Key word: - Novel polymer, Sorbitol, Detergents, Surfactants, Maleic anhydride, Synergistic combination. HLB- Hydrophilic–lipophilic balance.

Experimental investigation and modelling of CO2‐foam flow in heavy oil systems

In this work, the C14‐16alpha olefin sulphonate (AOS) surfactant, octylphenol ethoxylate (TX‐100), and methyl bis[Ethyl(Tallowate)]‐2‐hydroxyethyl ammonium methyl sulphate (VT‐90) surfactant were selected as representatives of anionic, nonionic, and cationic surfactant to stabilize foam. The effects of surfactant concentration and gas/liquid injection rates on foam performance were examined by performing a series of oil‐free foam flow tests by injecting CO2and a foaming surfactant simultaneously into sandpacks. Foam flooding was conducted as a tertiary enhanced oil recovery (EOR) method after conventional water flooding and surfactant flooding. Furthermore, a new method was proposed to determine the residual oil saturation. The foam stability in the presence and absence of heavy oil was studied by a comparative evaluation of the mobility reduction factor (FMR) in both cases. The foam fractional flow modelling by Dholkawala and Sarma[36]was modified based on experimental results obtained in this study. The range of the ratio of two important model parameters (Cg/Cc) at various foam qualities was determined and could be used for large‐scale predictions. The results showed that during the oil‐free foam displacement experiments higher foam apparent viscosities () were attained at lower gas flow rates and the maximum was attained at a total gas and liquid injection rate of 0.25 cm3/min with a gas fractional flow ratio of 0.8 for the foam in the absence of oil. The presence of oil reduced the foam mobility reduction factors (FMR) to different degrees withFMR‐without oil/FMR‐with oilranging from 4.25–13.69, indicating that the oil had a detrimental effect on the foam texture. The foam flooding successfully produced an additional 8.1–21.52 % of OOIP, which can be attributed to the combined effect of increasing the pressure gradient and oil transporting mechanisms.

Preparation of alanine and tyrosine functionalized graphene oxide nanoflakes and their modified carbon paste electrodes for the determination of dopamine

Herein, established the synthesis of graphene oxide (GO) by Hummers Method with addition of KMnO4 followed by thermal heating at 80°C. The obtained GO was further functionalized by alanine and tyrosine. The prepared GO, alanine functionalized GO nanoflakes (AGONF) and tyrosine functionalized GO nanoflakes (TGONF) were characterized by spectroscopic technique using energy-dispersive spectroscopy (EDS), quantitatively by scanning electron microscopy (SEM) and structural studies along with interlayer distance verified through X-ray diffraction technique. Afterwards, the prepared AGONF and TGONF were used as the modifier for the carbon paste electrode (CPE). The electrochemical behavior of the AGONF and TGONF modified carbon paste electrodes (MCPEs) towards dopamine (DA) in phosphate buffer solution (PBS) were examined by cyclic voltammetric (CV) technique and the obtained consequences showed good electrocatalytic activity of MCPEs by increasing the redox peak current with a lower potential difference compared to the bare CPE (BCPE). The AGONF and TGONF MCPEs were further used for the optimization studies. From the pH studies, it was found that the equal number of proton and electron transfer reaction involved in both the modified electrodes. The scan rate studies demonstrate the adsorption controlled electrode process at AGONF MCPE and diffusion controlled at TGONF MCPE. The oxidation peak current increased linearly with two concentration interval of DA at a range of 2–7μM and 10–30μM in presence of PBS (pH 7.4) at MCPEs and the limit of detection (LOD) were found to be 0.84μM and 0.96μM for first interval DA concentration range (2–7μM) at AGONF and TGONF MCPE. The stability, repeatability and reproducibility of functionalized GO nanoflakes MCPEs at DA were studied and established excellent characteristics. The newly developed functionalized GO nanoflake electrodes were successfully tested in DA injection sample. Furthermore the functionalized GO and surfactant (Sodium Alpha Olefin Sulphonate (SAOS)) immobilized functionalized GO MCPEs were examined for simultaneous determination of DA and ascorbic acid (AA) by differential pulse voltammetric technique.

Determination of the most significant variables affecting the steady state pressure drop in selected foam flow experiments

Abstract Foam generated with a surfactant solution and nitrogen is used for oil recovery, acid diversion and aquifer remediation. In laboratory experiments, the foam mobility is expressed in terms of the pressure drop across the porous medium and is related to many physical processes. There is lack of data that relate the pressure drop to a combination of three or more variables simultaneously. This paper investigates the steady state pressure drop for a combination of six variables, viz., permeability, surfactant concentration, pH, salinity, surfactant solution velocity and gas velocity. Fourteen pressure drop histories were measured for an Alpha Olefin Sulphonate solution before and after the injection of nitrogen gas across the unconsolidated sandpacks of two median grain sizes and across a Bentheimer consolidated core. Our data set was combined with data sets from the literature leading to 157 data points. Symbolic regression was applied to the entire data set to produce a number of analytical expressions describing the interactive effect of the variables without prior knowledge of an underlying physical process. A simple model with only one fitting parameter was selected to compare with the experimental data. The slope between the observed pressure drop and the predicted pressure drop turns out to be 0.85±0.03. A sensitivity analysis of the chosen model shows that the variables affecting the predicted pressure drop, in order of importance, are permeability, salinity and surfactant solution velocity. The precision of the model parameter was determined by a bootstrap method. The pressure drop from our data set and one specific data set from the literature show significant deviation with respect to the pressure drop obtained from the regression equation. Possible reasons are that the specific data set from the literature uses mixtures of surfactants and that our data set is confined to conditions that lead to low pressure drops. The purpose of the data driven model applied to experimental data is only to improve the models based on physical processes, i.e., mechanistic models. In addition the data driven model can indicate the variable spaces for which more experiments are needed.

Advances in Evaluation of Surfactant Performances at High Temperature by Static Foam Tests

—Foam stability and mobility reduction are the key parameters for foam assisted enhanced oil recovery. The harsh conditions such as high temperature, pressure and salinity present in an oil reservoir tend to destabilise the foam leading to poor sweep efficiency. Screening for the best performing foaming recipes has been performed to ascertain foam stability in the presence and absence of oil. Static foam test has been performed in order to study the foam stability and foam oil interactions at 90°C. Two anionic surfactants, alpha olefin sulphonate (AOS14-16) and methyl ester sulphonate (MES16-18) were mixed with betaine (foam booster) in different proportions to design the formulations. In addition to the ternary formulations, binary formulation involving surfactant and betaine were also evaluated for foam stability. For the study of oil effects on foaming performance of surfactant formulation, n-decane, diesel and Dulang crude oil are used. The recipes were evaluated by static foam tests to note the foam height and endurance time. It was found that the anionic surfactant played a major role in foam stability and the betaine was found less significant. However, the betaine alone was found effective for foaming and was poor for endurance time. While in mixture, the surfactant and betaine were found to interact strongly and a profound synergistic effect was noted. During oil interaction studies, the alkane type oils of low molecular weight become solubilised with surfactant molecule forming an emulsion and hence decimate the foam stability. However, higher alkanes with molecular chain more than ten carbon atoms (decane) stabilised the foam because of low solubilisation efficiency between surfactant and oil to form emulsions. The obtained results of the designed experiment have been analysed and discussed in detail to understand the contribution of individual component as well as their interactions with each other in order to stabilize foams.Keywords—Static Foam, Foam-Oil interactions, AOS, MES, Enhanced Oil Recovery

Electrochemical Determination of Folic Acid at Sodium Alpha Olefin Sulphonate Modified Carbon Paste Electrode: A Voltammetric Study

Sodium alpha olefin sulphonate (SAOS) was used for the modification of carbon paste electrode (CPE) to determine the electrochemical behavior of folic acid (FA) in 0.2M phosphate buffer solution (PBS) at pH 7.4 with the scan rate of 50 mVs-1. The effects of scan rate, concentration and simultaneous determination of FA at modified carbon paste electrode (MCPE) were studied. The effect of interference of dopamine was carried out and real sample analysis of FA was studied at MCPE. From the scan rate and concentration shows that, the overall electrode process was found to be diffusion-controlled at SAOSMCPE and detection limit was found to be 28.8 μM. The modified electrode (SAOSMCPE) exhibits good electrocatalytic activity towards the determination of folic acid when compared to BCPE. The same method can also be applied for other drug analysis.

The Incorporation of Silica Nanoparticle and Alpha Olefin Sulphonate in Aqueous CO2 Foam: Investigation of Foaming Behavior and Synergistic Effect

Foam behavior and synergistic effect of aqueous CO2 by three different sizes of hydrophobic silica nanoparticles with varying concentrations in presence of single anionic surfactant alpha olefin sulphonate with constant concentration of 1000 ppm were investigated in detail. The role of each size of silica nanoparticle was analyzed in view of the foamability, foam stability, and synergistic effect after equilibrium of aqueous CO2 foam. Result reveals that the bigger size of silica nanoparticle has better effect in low concentration and generally smaller size of silica nanoparticle has better influence on CO2 foam stability at higher concentrations.

Comparative Study of Effect of Surfactant‐Polymer Interactions on Properties of Alkyl Polyglucosides and Alpha Olefin Sulphonate

AbstractThe properties of Alpha Olefin Sulphonate (AOS) and Alkyl polyglucosides (APG) were studied in the presence and absence of nonionic polymers such as polyethylene glycol, poly vinyl pyrrolidone and methyl cellulose and hydroxy propyl cellulose. Properties like surface tension, foaming, viscosity and emulsification were studied at a constant concentration of polymer (0.1%) and varying concentrations of surfactant. It was found that at low surfactant concentrations there is an association between surfactant and polymer at the liquid/air surface in the case of an anionic surfactant and a nonionic polymer, which is not seen in the case of nonionic surfactants and nonionic polymers. A nonionic polymer reduces the surface tension of AOS by forming a surfactant‐polymer complex which in turn increases the foamability, emulsifying property and viscosity of solution. APG does not show any effect on its surface tension in the presence of nonionic polymers but its foamability and emulsifying properties are improved. Reduction in surface tension is not the only reason behind increased foamability in the presence of the polymer. Higher molecular weight polymers give a rich, creamy foam because of increased viscosity in the surfactant solution as compared to lower molecular weight polymers.

Studies in Detergency: Influence of Different Factors for Removing Motor Oil Stain from the Cotton Fabric

The ability of surfactants to remove a organic soil from the cotton fabric has been investigated using various parameters such as temperature and hardness of water. The surfactants such as alkylpolyglucosides (APG), sodium lauryl sulphate (SLS), and alpha olefin sulphonate (AOS) have been taken to formulate the detergent as such and in mixtures to evaluate the detergency performance to remove motor oil from the 100% cotton fabric. In the past, the detergency of nonionic APG surfactants has not been well studied. The behavior of commercial APG surfactants and mixtures of APGs with other common surface cleaning agents (SLS & AOS) in laundry applications has been investigated. Motor oil is the toughest soil to remove as it contains nonpolar organic compounds. The performance of detergency was evaluated at different temperatures (30°C, 45°C, and 60°C) and in the presence of hard water (40, 100, and 300 ppm).

Evaluation of Different Alkyl Polyglycoside Surfactants and Their Combination with Alpha Olefin Sulphonate for Detergency

Among all sugar‐based surfactants, alkyl polyglycosides (APG) are the most successful, with applications ranging from agricultural, chemicals, laundry detergents, and hard surface cleaners to personal care products. APGs show significant synergistic effects in conjunction with anionic surfactants. Alpha olefin sulphonate (AOS) is one such anionic surfactant that is fast gaining acceptability in detergents for its superior performance characteristics and enhanced biodegradability. The present article evaluates the detergency of APG surfactants with three different chain lengths C8/10, C12/14, and C12/18, against fatty soil, particulate soil, and oily soil. Further the synergistic effects with AOS on detergency performance of APG are studied.

Bestimmung der Verteilung der Kettenlänge anionischer Tenside / Determination of chain length distribution of anionic surfactants

The chain length distribution of sulphonated surfactants was determined by high resolution capillary gas chromatography. Prior to analysis the sulphonate functionality was converted into the methyl ester derivative. Two methods of derivatisation were investigated and compared. The procedure was used for the major types of anionic surfactants including alkane sulphonate, alkylbenzene sulphonate and alpha-olefin sulphonate.

Adsorption of Foam-forming Surfactants In Berea Sandstone

Abstract Adsorption measurements carried out with representatives of four classes of surfactant suitable for foam flooding (alpha olefin sulphonate, internal olefin sulphonate, linear xylene sulphonate, and betaine) on Berea sandstone at different conditions of temperature and salinity are described. Adsorption of (he anionic surfactants from a low salinity brine is low, but increases substantially at moderate salinities. Limited solubility of the anionic surfactant in aqueous media tends to drive these surfactants to the solid/liquid interface and can also lead to increased surfactant loss through precipitation. The betaine is highly soluble, but adsorbs very strongly on sandstone. Adsorption of this surfactant can be reduced by mixing it with an anionic surfactant. Introduction EOR production in North America is dominated heavily by gas or vapor flooding. Out of total of 371 EOR projects, 294 involve injection of steam CO2 or hydrocarbon solvent(1). Became of the low density and viscosity of the injected fluid, gas and vapor flooding processes tend to suffer from poor sweep efficiency. This problem may be alleviated through the use of mobility control foams(2,3). While the mechanism of lamella generation and collapse is crucial to foam performance and propagation, the maximum distance that a foam will travel is dictated by surfactant loses in the reservoir, caused by adsorption at the solid/liquid interface, precipitation, chemical degradation, and partitioning into an immobile oil phase. This paper deals with the last and frequently most important of these mechanisms. Surfactant classes most commonly applied in laboratory studies of EOR-foams and in field applications include alkyl aromatic sulphonates and olefin sulphonates. Since much of the EOR-foam literature deals with steam foams, surfactant selection has often been determined by the requirement of chemical stability at steam flood temperatures. The following ranking has been assigned to several surfactant classe in terms of their thermal stability(4) alkyl aryl sulphonates > olefin sulphonates > petroleum sulphonates > ethoxylated alcohols and ethoxylated sulphates. The surfactants that have been found the most thermally stable are also the most likely to precipitate in the presence of inorganic electrolyte. Surfactant solubility has been found to decrease in the following order(4); ethoxylated alcohols or sulphates > olefin sulphonates > petroleum sulphonates = alkyl aryl sulphonates. A characteristic of the surfactants most commonly described in connection with EOR-foams is thus their limited solubility in brines. The high molecular weight surfactant homologues suitable for steam-foams have very limited solubility in aqueous media and are expected to have a higher affinity for the solid/liquid interface than lower molecular weight homologues. Steam flood temperatures will favour low adsorption levels and increased solubility. During steam flooding, a surfactant encounters salinity and temperature gradients and a knowledge of the dependence of surfactant behavior on both parameters is required. Surfactants suitable for the extreme conditions of salinity and hardness encountered in many Alberta reservoirs have been identified(5). Detailed measurements of the adsorption properties of these surfactants have been previously described(6–8). By contrast, reported adsorption data for surfactant classes commonly used for steam flood applications are rather limited(9–15).

Retention Of Foam-Forming Surfactants At Elevated Temperatures

Abstract There is considerable interest in the use of foam-forming surfactants for mobility control in steamfloods. To provide effective mobility control, the injected surfactant must propagate from the injection well toward the production well. One of the important parameters affecting foam propagation through the reservoir is the retention of surfactant due to its adsorption on reservoir rock. Because the foam encounters a range of temperatures and salinities between the injection and production wells, it is necessary to evaluate the temperature and salinity dependence of surfactant adsorption. This paper reports on the results of adsorption measurements an elevated temperatures for two typical commercially available surfactants currently in use for such applications an alpha olefin sulphonate and a synthetic alkyl toluene sulphonate. Adsorprion experiments were performed in unconsolidated sand cores of temperatures ranging from 50 °C to 150 °C The role of clays in surfactant adsorption was investigated by comparing the results obtained in clean sand with those obtained in cores containing known amounts of clays. Surfactant adsorption was de/ermined from surfactant concentration profiles at the core outlet. This analysis can be used for evaluating the whole adsorption isotherm provided a specific adsorption model (for example, the Langmuir isotherm) is assumed. Automatic history matching procedures for that purpose were tested and their efficiency evaluated. The results show that adsorption of both surfactants in clean sand is relatively low and decreases with increasing temperature. The alkyl toluene sulphonate was found to adsorb more than the alpha olefin sulphonate, and its adsorption was more strongly affected by salinity. The presence of clays in the core resulted in increased surfactant adsorption. Introduction The injection of foam-forming surface active agents in steamflooding applications has the potential for improving the performance of this enhanced oil recovery (EOR) process by two mechanisms. It can improve conformance by reducing steam mobility in the steam zone, and it can increase the oil displacement efficiency in the swept zone. Irrespective of which mechanism is dominant, for economic reasons it is desirable to inject the lowest surfactant concentration which is still effective in improving oil recovery. The rate of propagation of dilute surfactant solutions through the reservoir may be strongly affected by adsorption of the injected surfactant on reservoir rock surfaces. Thus the evaluation of surfactant adsorption should always be included when assessing the effectiveness of the surfactant in improving steamflood performance. As the injection of steam may result in large temperature and salinity gradients in the reservoir, a complete evaluation of surfactant adsorption requires its measurement over a wide range of temperatures and salinities. This paper describes the results of adsorption measurements for two types of commercially available foam-forming surfactants, an alpha olefin sulphonate and a synthetic alkyl toluene sulphonate. Adsorption of these two surfactants in unconsolidated cores saturated with either distilled water or a lowsalinity synthetic brine was evaluated at three temperatures. The solid used in the study was either a clean silica sand or a mixture of the sand and one of two types of pure clays montmorillonite and kaolinite.