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Nonionic Surfactant for Enhanced Oil Recovery from Carbonates: Adsorption Kinetics and Equilibrium Mohammad Ali Ahmadi,† Sohrab Zendehboudi,*,‡ Ali Shafiei,§ and Lesley James∥ †

Faculty of Petroleum Engineering, Petroleum University of Technology, Ahwaz, Iran Chemical Engineering Department, University of Waterloo, Waterloo, Ontario, Canada, N2L 3G1 § Department of Earth and Environmental Sciences, University of Waterloo, Waterloo, Ontario, Canada, N2L 3G1 ∥ Faculty of Engineering and Applied Science, Memorial University of Newfoundland, St. John’s, NL, Canada, A1B 3X5 ‡

ABSTRACT: Around 40% of the current world conventional oil production comes from carbonate reservoirs, dominantly mature and declining giant oilfields. Tertiary oil production methods as part of an Enhanced Oil Recovery (EOR) scheme are inevitable after primary and secondary oil production. The goal of surfactant flooding is to reduce the mobility ratio by lowering the interfacial tension between oil and water and mobilizing the residual oil. This paper highlights adsorption kinetics and equilibrium of Glycyrrhiza Glabra, a novel surfactant, in aqueous solutions for EOR and reservoir stimulation purposes. A conductivity technique was used to assess adsorption of the surfactant in the aqueous phase. Batch experimental runs were also performed at various temperatures to understand the effect of adsorbate dose on the sorption efficiency. The adsorption kinetics was experimentally investigated at room temperature (27 °C) by monitoring the uptake of the Glycyrrhiza Glabra as a function of time. The adsorption data were examined using different adsorption equilibrium and kinetic models. The Langmuir isotherm suits the equilibrium data very well. A pseudo-second order kinetic model can satisfactorily estimate the kinetics of the surfactant adsorption on carbonates. Results obtained from this research can help in selecting appropriate surfactants for design of EOR schemes and reservoir stimulation plans for carbonate reservoirs.

1. INTRODUCTION Carbonate rocks cover around 20% of the earth crust and contain over 40% of the world’s proven conventional oil reserves and also over 20% of the world’s endowment of heavy oil, extra heavy oil, and bitumen.1−10 More than 40% of the current world oil production comes from Naturally Fractured Carbonate Reservoirs (NFCRs), dominantly mature and rapidly declining giant oilfields in the Middle East.5−10 Primary and secondary oil production methods result in recovery factors (RF) of, commonly, not greater than 0.45.1−5 Meaning that over 50% of the oil originally in place (OOIP) is trapped in the reservoir rock as residual oil due to mobility issues and capillary pressure barriers.1−25 Hence, implementation of tertiary oil production techniques as part of an Enhanced Oil Recovery (EOR) scheme is inevitable to unlock this immense oil resource. Chemical EOR methods have not historically been responsible for significant additional recovery, worldwide. Nevertheless, surfactants are being increasingly used as a well stimulation or wettability alteration agent in EOR projects in carbonates. This along with the price of oil is a strong reason for scientists to continue the advancement of surfactant research in EOR.1−25 Among chemical EOR techniques, surfactant flooding aims to lower the mobility ratio by reducing the interfacial tension between oil and water and mobilizing the residual oil to the production well. This is feasible via adsorption of the surfactants on the reservoir rock.7,26−30 Surfactant flooding has been tried for a number of conventional oil reservoirs around the world with some success stories (e.g., Yates field in Texas9,31,32 and Cottonwood Creek in Wyoming),5,9,32−36 but it has largely proved inefficient due to the cost of surfactant loss © 2012 American Chemical Society

in the porous medium as well as issues with adsorption efficiency and negative reactions with the reservoir rock.36−38 Surfactants can be classified into different groups based on the ionic nature of the headgroup, namely anionic, cationic, nonionic, and zwitterionic.39,40 Nonionic surfactants are generally nonvolatile and benign environmentally and are considered as suitable alternatives for traditional solvents due to their ability to separate organic compounds from solid samples. Nonionic surfactants have effective solubilization toward water-insoluble or moderately soluble organic compounds.41 This property makes nonionic surfactants proper candidates for the separation of polar and nonpolar compounds from different solid materials such as separation of aromatic hydrocarbon from solid environmental phases.42−48 Other factors affecting the rate of surfactant adsorption include rock surface charge, fluid interface, and surfactant structure.49−51 Adsorption of various commercial surfactants is well treated in the open literature.51−56 Surfactant adsorption in porous systems typically occurs through a range of complex phenomena (e.g., mass transfer and reaction). Surfactant adsorption is defined as a phenomenon where transport of surfactant molecules from the bulk phase onto the interface at solid−liquid boundary occurs. This process can be explained as the interface is energetically favored by the surfactant compared to the bulk phase.54,55 The surfactants may adsorb on soils or sediments as a single monomeric layer at low concentrations of aqueous Received: Revised: Accepted: Published: 9894

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side chain enables saponin to change to a foam. A large number of synthetic surfactants such as lipopeptide biosurfactants, alkyl poly glycosides, and alkyl sulfates surfactants, with lipophilic and hydrophilic molecular groups have the same structure.61 Three cyclopeptide alkaloids, as well as, four saponin glycosides, and several flavonoids can be extracted from the leaves of Glycyrrhiza Glabra. Saponin, a biosurfactant, is produced from Glycyrrhiza Glabra leaves. The leaves were collected from southern Iran, and the surfactant was extracted from the leaves using the spray dryer technique. The total extracted powder contains saponin and flavonoids. The powder is light brown in color and soluble in water and alcohol.61−64 The powder density is 0.45 g/cm3, and a 1 wt % aqueous solution has a pH of 5.8−6.0. Saponin is a natural and biodegradable nonionic surfactant. Properties of this novel surfactant are summarized in Table 1.

surfactant. If the surfactant concentration increases, then the adsorbed surfactant monomers tend to aggregate and form micelle-like structures. Depending on the number of layers of the aggregated surfactant, the micelles are called admicelles for one layer and hemimicelles for the two other layers.52−55 Gaudin and Fuerstenau (1955) showed that when the micelles structures make an aggregate on a solid surface, the rate of adsorption might quickly increase until the solid interface is covered completely by bilayers of the surfactant. They used the concept of critical micelle concentration (CMC) to explain this phenomenon. According to their definition, the surfactant aggregation occurs at concentrations lower than the CMC but greater than the hemimicellar concentration (HMC).52 Adsorption kinetics and equilibrium of surfactants are dependent on the nature of or properties of the surfactants and also the solid−liquid surface.53−56 Wayman (1963) and Scamehorn (1980) independently studied the adsorption of a dilute solution of sodium alkyl benzene sulfonate (SDDBS) as a surfactant on various clay minerals (e.g., Kaolinite).57,58 They concluded that the adsorption isotherms match the Langmuir equation, and they can be explained by using the Truber diagram. Moreover, a number of researchers (e.g., Meader (1952)51 and Trogus (1979)59) investigated the adsorption of sodium alkyl benzene sulfonate on bioglass, kaolin, and Berea sand core. They indicated that the Langmuir isotherm is not appropriate to describe the equilibrium adsorption of these particular materials.51,59 Based on their experimental results, a maximum adsorption magnitude was observed, occasionally followed by a minimum extent. Gogoi (2009) reported the adsorption equilibrium of Na-lignosulfonate onto reservoir rocks from Oil India Limited.60 He demonstrated that adsorption increases with increasing NaCl concentration but decreases with increasing pH.60 The adsorption mechanism of Glycyrrhiza Glabra on the surface of carbonate rock is not yet reported in the literature. This paper highlights the adsorption behavior of Glycyrrhiza Glabra in aqueous solutions as a new nonionic surfactant to be implemented for EOR schemes in carbonates. Adsorption of the studied surfactant was evaluated using a conductivity technique for aqueous phase. Batch experiments were also conducted to investigate the influence of adsorbate dose on sorption efficiency at different temperatures. In addition, the adsorption kinetics was experimentally investigated at 27 °C with recording the uptake value of the Glycyrrhiza Glabra versus time. The adsorption equilibrium data were also examined with four different adsorption kinetic models (Langmuir, Freundlich, Temkin, and linear expressions), and the adsorption parameters were determined for all isotherm models, over the entire range of the process conditions. The results are useful to screen surfactants for use in EOR and reservoir stimulation plans for carbonate petroleum reservoirs.

Table 1. Properties of Glycyrrhiza Glabra, a Novel Surfactant parameter product used part preparation description color solubility in cold water solubility in alcohol pH value (10 wt % solution) density loss on drying (LOD) at 110 °C after 6h total ash at 550°C after 4 h applications

remarks total extract powder of Glycyrrhiza Glabra roots spray drier fine powder brown soluble soluble 5.9−6.0 0.41 g/cm3 3.48%−4.0% 9.7%−10.0% medicine, surfactant

2.2. Adsorbent. Carbonate rock cores were taken from the upper Sarvak Cenomanian formation of the Azadegan oilfield located in the Persian Gulf. The Cenomanian Sarvak formation is mainly composed of highly fractured marly nerritic and pelagic limestone with interbedded shale layers. This formation is divided into three main sections. The upper Sarvak mostly consists of clean limestone with slight argillaceous limestone. The middle Sarvak is mostly shale and marls are dominant. The lithology of the lower Sarvak is mostly marly limestone with some shale bed intercalations. The porosity of the examined limestone samples were measured to be approximately ∼12%, and the permeability was on the range of 1−10 mD (very low permeablility matrix). The average water saturation within the reservoir is reported on the range of ∼10%. The carbonate samples were cracked into small parts by jaw crusher and then grounded into fine particles using a laboratory mill. After exposing the samples to free-air for one day, a laboratory oven operating at 105 °C was employed to dry the carbonate powder. Dried carbonate samples were sieved by sieves No. 50 and No. 70 to obtain particles with diameter lower than 297 μm and bigger than 210 μm. The semiquantitative mineral composition of the crushed carbonate rock determined by X-ray diffraction (XRD) is presented in Figure 1. Based on the XRD, the crushed carbonate samples used in this research work contain calcite (65.38 wt %), dolomite (3.13 wt %), orthoclase (28.89 wt %), clay (1.83 wt %), and other minerals (0.77 wt %).

2. MATERIALS AND METHODS 2.1. Surfactant. Glycyrrhiza Glabra is a tree with small spiny branches, commonly found in Jordan, Iran, Iraq, and Egypt. The concentration of the Saponins in Glycyrrhiza Glabra is fairly high (e.g., 25 wt %).61 Saponins are natural surfactants existing in more than 500 plant types.62,63 Their molecules include hydrophobic and hydrophilic parts. The hydrophobic group is made of a triterpenoid or steroid backbone, and the hydrophilic part contains numerous saccharide deposits, joined to the hydrophobic scaffold through glycoside bonds.64 The combination of the nonpolar sapogenin and water-soluble 9895

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Figure 1. XRD of the crushed carbonate rocks tested.

2.3. Preparation of Surfactant Solution. Specific stock solutions of Glycyrrhiza Glabra with concentrations ranging from 1000 mg/L to 80000 mg/L were prepared by dissolving 0.10−8.00 g of Glycyrrhiza Glabra in 1000 mL of deionized water in a volumetric flask. These solutions were then diluted to obtain standard solutions containing 1000, 5000, 10000, 15000, 20000, 40000, 50000, 60000, 70000, and 80000 mg/L of Glycyrrhiza Glabra. 2.3.1. CMC Measurements. There are several methods such as UV−vis spectra, fluorescence emission spectra, and electrical conductivity to measure the CMC. In this study, the conductivity method was selected to carry out the CMC measurements. Concentration of the Glycyrrhiza Glabra samples used was on the range of 1000−80000 ppm. The conductivity of the different solutions was determined from high to low concentrations. The conductivity meter (Crison Instruments) was calibrated by using a standard solution. The conductivity of the solution was measured by immersing the probe in the solution as shown in Figure 2. The electrode was washed with distilled water before and after every trial to ensure accuracy of the conductivity measurements. In this study, the value of CMC is determined as the cross point of the two straight lines drawn in Figure 2 for high and low concentrations of the surfactant. Based on this method, the CMC for Glycyrrhiza Glabra is about 3.5 wt %. 2.4. Adsorption Experiments. Batch experimental runs were performed by equilibrating 8 g of a crushed carbonate sample in a 40 mL of Glycyrrhiza Glabra solution ranging from 1000 to 80,000 ppm. The bottles were then shaken at a controlled room temperature.

Figure 2. Conductivity versus surfactant concentration for the Glycyrrhiza Glabra adsorption.

Changes in surfactant concentration during the adsorption test runs were determined using the conductometry method. The concentration of surfactant adsorbed on the solid surface (carbonate rock) was determined from the difference between the aqueous phase surfactant concentration before and after adsorption. The adsorption rate versus equilibrium surfactant concentration is presented in Figure 3, where the adsorption rate (q) measured with this technique is calculated as q= 9896

msolution × (C o − C) × 10−3 mcarbonate

(1)

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Figure 4. Adsorption analysis of experimental data based on the Langmuir adsorption model. Figure 3. Adsorption density versus surfactant equilibrium concentration.

an infinite surface coverage inferring multilayer sorption on the surface.66,67 The Freundlich isotherm model is given as66,67 qe = K f Ce1/ n

where q = surfactant adsorption rate on the rock surface, mg/g-rock; msolution = total mass of solution in the original bulk solution, g; Co = surfactant concentration in initial solution before equilibrated with the carbonate rock, ppm; C = surfactant concentration in aqueous solution after equilibrated with the carbonate rock, ppm; mcarbonate = total mass of the crushed carbonates, g.

(3)

where n and Kf are the Freundlich constants. Figure 5 presents the adsorption behavior of the surfactant on the carbonate samples, based on the Freundlich isotherm.

3. EQUILIBRIUM ADSORPTION MODELS For any adsorption system, an adsorption isotherm model is necessary in order to forecast the extent of loading on the adsorption matrix at a particular concentration of the adsorbate. The four well-known general adsorption isotherms employed here to describe the equilibrium adsorption behavior are explained here, briefly. 3.1. Langmuir Isotherm. Assuming an entirely homogeneous surface for adsorption, the Langmuir isotherm model used to predict equilibrium adsorption rate (qe) is obtained as follows65,66 q KadCe qe = o 1 + KadCe (2)

Figure 5. Freundlich isotherm model for the equilibrium data of Glycyrrhiza Glabra adsorption.

where qo (mg/g) and Kad (L/mg) represent the adsorption capacity in the Langmuir model and adsorption equilibrium constant, respectively. If the adsorption equilibrium data follow the Langmuir isotherm model, a plot of 1/qe against 1/Ce should be linear (Figure 4). The slope is 1/(qo Kad) and the y-intercept is 1/qo. 3.2. Freundlich Isotherm. An empirical equation was established by Freundlich (1906) to describe the adsorption equilibrium process, assuming the adsorbent has a heterogeneous surface with different categories of adsorption sites.67 The results from the study showed that the ratio of equilibrium adsorption, qe, for a particular adsorbent to the concentration of adsorbate in a solution, Ce, is not a constant value over a range of solution concentrations.67 This isotherm model is unable to estimate the amount of adsorbate required to saturate the adsorbent. Hence, the adsorption model theoretically predicts

3.3. Temkin Isotherm. The Temkin isotherm is generally expressed in the following linear form66,68,69 qe = Bln K t + Bln Ce

(4)

where B and Kt are the Temkin constant and equilibrium binding constant, respectively. The experimental adsorption data analyzed according to Temkin is shown in Figure 6. 3.4. Linear Isotherm. The simplest type of adsorption isotherm model is developed on the basis of the Henry equation as follows66,70 qe = KHCe

(5)

where qe is the amount of solute adsorbed per unit mass of adsorbent under equilibrium condition, Ce is the equilibrium 9897

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Figure 6. Adsorption equilibrium data based on the Temkin isotherm model.

Figure 8. Adsorption of surfactant versus time for different surfactant concentrations.

4.1. Pseudo-first Order Kinetic Model. The pseudo-first order expression of Lagergren is presented as follows69−72 dqt dt

= K1(qe − qt )

(6)

qt and qe correspond to the extent of adsorbate adsorbed onto unit mass of adsorbent at time (t) and equilibrium condition, respectively. K1 is the rate constant of pseudo-first order adsorption reaction. After integrating over the boundary conditions (qt = 0 @t = 0 and qt = qt @ t = t), the above differential equation (eq 6) changes to a first-order linear relationship as given below69−72

Figure 7. Linear isotherm model for the surfactant/carbonate adsorption system.

ln(qe − qt ) = ln(K1qe) − K1t

(7) −1

In eqs 6 and 7, unit of K1 is min . Also, both qe and qt have the unit of mg/g. 4.2. Pseudo-second Order Kinetic Model. The pseudosecond order kinetic model is expressed in a differential form as the following69−72

concentration, and KH represents a constant for the linear isotherm model in units of L/m2. The linear isotherm model for the experimental data of this study is shown in Figure 7.

dqt

4. ADSORPTION KINETICS Rate of adsorption reaction is the second important component for assessment of an adsorption process. The adsorption kinetics is strongly dependent on process condition and interactions between adsorbent and adsorbate substances. The retention time needed for completion of the adsorption reaction is obtained from the rate of adsorbate uptake which can be determined by employing various kinetic equations through a comprehensive study. Several attempts have been made to elucidate the adsorption kinetics in the form of a general correlation for adsorption processes involving liquid/ solid phases. In this paper, four common kinetic models, namely, pseudo-first order,69−72 pseudo-second order,69−72 intradiffusion,69−72 and Elovich kinetic rates,69−72 were examined to find out the adsorption rate of Glycyrrhiza Glabra onto the carbonate surface. The adsorption kinetic experiments were performed at room temperature (27 °C) by recording the uptake of Glycyrrhiza Glabra versus time as presented in Figure 8.

dt

= K 2(qe − qt )2

(8)

This adsorption kinetic model is usually valid for solid−liquid systems.69−72 By integrating and rearranging eq 8, a linear form for the pseudo-second order reaction rate is obtained as eq 9 t 1 t = + qt qe K 2qe2 (9) where K2 (g/mg·min) is the rate constant of pseudo-second order adsorption. Other variables contributing in the pseudosecond order model have the same definitions and units as those in eqs 6 and 7. The slope and intercept for the linear plot of eq 9 enable us to calculate the magnitudes of equilibrium adsorption (qe) and the rate constant (K2). It has been reported that the pseudo-second order rate is a suitable kinetic model to predict the adsorption behavior of the most experimental liquid−solid cases within the whole range of process condition.69−72 9898

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plotted in order to obtain the CMC magnitude from the inflection point of the data shown in Figure 2. When concentration of the surfactant solution increases to a definite value, its ions or molecules will approach the association reaction and aggregate to form micelles as a change in conductivity is observed. Precise experimental measurements using well purified apparatus showed that fairly slow and continuous variations in physicochemical characterizations of the solutions take place close to the CMC. In this case, the micelles alter to be polydisperse, and substantial changes in the monomer activities occur at the concentrations greater than the CMC. The influence of initial concentration of the Glycyrrhiza Glabra on the amount of adsorption is presented in Figure 3. The equilibrium adsorption, as shown in Figures 3 and 8, was reached within 10 days for most initial concentrations. An increase in the concentration of surfactant leads to an increase in adsorption capacity of the surfactant onto the carbonate samples. This is due to the increase in the concentration gradient between the bulk and the surface of the carbonate rock. The impact of contact time on efficiency of the surfactant adsorption onto the carbonate rock was studied in order to determine the rate of surfactant adsorption. The adsorption rate of the surfactant as a function of contact time was measured for various initial concentrations of Glycyrrhiza Glabra within the range of 0.1−8.0 wt % (Figure 8). Clearly, as seen from Figure 3, the maximum adsorption rates were attained nearly in the first 10 days for all studied initial concentrations of the surfactant. In the beginning of the process, the adsorption rate is greater, since more carbonate surface area is available for the surfactant adsorption. As the adsorbed substance proceeds formation of a monolayer, the capacity of the carbonate sample declines, and the controlling rate for the uptake is the rate at which the solute solution is moved from the external to the internal sites of the carbonate particles. It was found that the rate of adsorption decreases in the next steps. This is possibly due to the slow phenomenon of pore diffusion which mainly contributes in the transportation of the surfactant ions into the bulk of carbonate rocks. 5.2. Adsorption Isotherms. Adsorption isotherm models can help illustrate adsorption mechanism of the surfactant on the surface of carbonate rocks. Adsorption isotherms are described by particular constant parameters which determine the surface characterizations and affinity for the degree of adsorbent substance toward the adsorbed surfactant. To perform an optimized design for a sorption process, it is essential to consider the most proper correlations for equilibrium curves. Langmuir, Freundlich, Temkin, and linear isotherm models were employed to characterize the equilibrium adsorption. Experimental sorption tests were carried out at the equilibrium time for different doses of Glycyrrhiza Glabra as a new surfactant introduced in this paper. In the Langmuir isotherm, the constants qo and Kad are associated to the adsorption capacity and energy of adsorption, respectively. When 1/qe versus 1/Ce was plotted using the experimental data, a straight line was obtained with slope of 1/qo Kad and R2 = 0.9964 (Figure 4), indicating that the surfactant adsorption onto the carbonate rock follows the Langmuir isotherm model very well. The Langmuir constants Kad and qo were computed from the slope and intercept of the linear plot for this isotherm, and their magnitudes are tabulated in Table 2. The fit of data to the Freundlich isotherm model generally points out the heterogeneity of the adsorbent surface. The value of exponent (1/n) is a criterion to determine capability and capacity of the adsorbent surface/adsorbate solute system:66,67,69 The values of the Freundlich isotherm

To approximate the initial adsorption rate and halfadsorption time, eqs 10 and 11 are given as69−72

h = K 2qe2

(10)

t1/2 = 1/K 2qe

(11)

The variables h and t1/2 are the initial adsorption rate and halfadsorption time, respectively. 4.3. Intraparticle Diffusion Model. First-order or secondorder kinetic models are basically utilized for determination of the reaction type and the amount of adsorption rate. In order to comprehend the diffusion mechanism in an adsorption process, it is crucial to employ various diffusion models.66,69−72 One of the proposed models is the intraparticle diffusion that looks useful as well as simple to determine important aspects of diffusion mechanism. The intraparticle diffusion model is expressed as follows66,69−72

qt = K i × t 1/2

(12) 1/2

According to eq 12, the slope of linear plot (qt versus t ) is the rate constant of the intraparticle diffusion (Ki). If the regression line relating t1/2 to the adsorption rate (qt) has an intercept of zero, the dominant mechanism in adsorption is the intraparticle diffusion. If not, other mechanisms are also engaged in the adsorption reaction. Figure 11 shows adsorption rate (qt) versus time squared (t1/2), based on the intraparticle diffusion model. Relationship between the experimental data and the data predicted by the kinetic model reveals the multilinearity nature of adsorption kinetics for the Glycyrrhiza Glabra/carbonate case in this study. 4.4. Elovich Model. The differential form of Elovich equation is typically expressed as66,70−72

dqt dt

= αe−βqt

(13)

where qt is the adsorption capacity at time t in units of mg/g. α (mg/g·min) and β (mg/g·min) are the initial adsorption rate and adsorption constant for a certain experiment, respectively. Assuming α β t ≫ 1, and then integrating over the boundary conditions (qt = 0 @ t = 0; qt = qt @ t = t), eq 13 is simplified as follows66,70−72 ln(αβ) ln(t ) 1 = + q qt β β t

(14)

Therefore, if a plot of qt versus ln (t) yields a straight line, the constants of the Elovich kinetic model (α and β) are calculated from the slope and intercept of the linear graph (Figure 12).

5. RESULTS AND DISCUSSION Adsorption equilibrium and kinetics of the aqueous solutions of Glycyrrhiza Glabra, as a nonionic surfactant, is addressed here in this section. 5.1. Important Parameters. Major factors affecting Glycyrrhiza Glabra adsorption on the carbonate samples are considered to investigate the interaction mechanism of a liquid phase and a solid phase in a particular case elaborated here. Quantifying the critical micelle concentration (CMC) is important to understand the active surface chemistry of Glycyrrhiza Glabra in the solute and in turn the adsorption mechanism of the surfactant on the surface of the adsorbent. Conductivity values versus surfactant concentrations were 9899

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Table 2. Parameters Calculated for the Different Adsorption Models Employed isotherm

correlation

Langmuir

1/qe = 0.0722/Ce + 0.0196

Freundlich

qe = 9.7946(Ce)0.8412

Temkin

qe = 10.599 ln(Ce) + 17.7110

linear

qe = 6.0665 Ce + 4.8148

parameters R2 0.9964 R2 0.9891 R2 0.8733 R2 0.9307

qo 51.02 n 0.8412 Kt 5.31 KH 6.0665

Kad 0.27 Kf 9.7946 B 10.599 c 4.8148

parameters are listed in Table 2 for the adsorption system described in this study. For the Temkin isotherm model, a plot of qe against ln (Ce) (Figure 6) gives the magnitudes of the constant parameters including Kt and B. Kt (L/mg) represents the equilibrium binding constant which is related to the maximum binding energy. Parameter B is also corresponding to the adsorption heat. The values of the constants are listed in Table 2 obtained based on the adsorption equilibrium data analyzed with the isotherm model. A graph of the amount adsorbed per unit mass of the adsorbent, qe, versus equilibrium concentration, Ce, has a slope of KH for the linear isotherm as shown in Figure 7. Table 2 includes values of the parameters (e.g., KH and R2) for this isotherm, as well. The coefficient of determination (R2) obtained for the Temkin isotherm model is 0.873, much less than the R2 values for the linear plots obtained from the Langmuir, Freundlich, and linear isotherm equations. The values of R2 indicate that the experimental adsorption data are better fitted with the Freundlich and Langmuir isotherm models compared to the rest of the isotherms used in this study (Table 2). 5.3. Adsorption Kinetics. In this section, the experimental adsorption data were examined with four common kinetic models in order to comprehend the adsorption kinetics of the surfactant onto the crushed carbonates. Surfactant adsorption kinetics onto carbonate rocks was modeled by the pseudo-first order kinetic rate (Figure 9). The slope and intercept of the graph of ln(qe − qt) versus t for the Glycyrrhiza Glabra/carbonate system enabled to determine the rate constant of this kinetic model (K1) and equilibrium adsorption rate (qe), respectively. The Lagergren plots for the sorption process at different initial concentrations of the surfactant are presented in Figure 9. It is evident that the adsorption system obeys the Lagergren model just in the beginning of the process for a short time period. It can be concluded that only the early stage of the adsorption process correlates with the Lagergren model. Hence, an appropriate kinetic reaction model is required to elucidate the kinetics of the Glycyrrhiza Glabra onto carbonate samples. Table 3 presents the parameters of pseudo-first order kinetic model for different surfactant concentrations employed in this experimental work. Adsorption kinetic plot for Glycyrrhiza Glabra on the basis of the pseudo-second order rate is shown in Figure 10. The adsorption kinetic data of Glycyrrhiza Glabra, a new nonionic surfactant, fits very well into the pseudo-second order rate contrasting the pseudo-first order kinetic model. The parameters of the pseudo-second order rate at various initial surfactant dosages are listed in Table 3. As seen in the table, the

Figure 9. Pseudo-first order plot for surfactant adsorption onto carbonate rock: a) surfactant concentration, wt% [0.5, 1.0, 1.5, 2.0] and b) surfactant concentration, wt% [4.0, 5.0, 6.0, 7.0, 8.0].

correlation coefficients obtained for the pseudo-second order kinetic model have higher values (R2 > 0.99) compared to the R2 magnitudes for the pseudo-first order kinetic model. In addition, the equilibrium adsorption rates (qe) estimated by the second-order rate model are in an acceptable agreement with the experimental values of the equilibrium capacity. These findings propose that the adsorption kinetics of Glycyrrhiza Glabra on the carbonate adsorbent can be predicted, more suitably, by the pseudo-second order model, over the whole ranges of surfactant concentrations and process time periods. According to Figure 10 and Table 3, it can be concluded that Glycyrrhiza Glabra experiences a high initial adsorption kinetic rate, h, with short halfadsorption time, t1/2, for the carbonate rocks. The likelihood of the intraparticle diffusion in the present experimental work was investigated by using eq 12. If the intraparticle diffusion is the prevailing transportation mechanism, then the adsorption kinetic rate (qt) should linearly proportional with t1/2, and the linear plot will have an intercept of zero. Otherwise, some other controlling mechanisms are involved in the adsorption process.66,67,69 The intraparticle diffusion plot of the kinetic data for Glycyrrhiza Glabra is depicted in Figure 11. More information about the adsorption reaction rate of this new surfactant onto carbonate samples is summarized in Table 3, based on this kinetic model. The values of R2 reveal that the intraparticle diffusion theory is not an inappropriate kinetic model for the surfactant investigated as the correlation coefficients (R2) for all examined surfactant concentrations were found very small (R2 ≪ 1). Furthermore, Figure 11 and Table 3 demonstrate that other adsorption mechanisms along with diffusion contribute in the interactions between the surfactant and adsorbent. 9900

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Table 3. Kinetic Rates of the Surfactant with Various Concentrations on the Absorbent, Based on Four Different Adsorption Kinetic Models model pseudo-first order

pseudo-second order

C (wt %)

correlation

0.5 1.0 1.5 2.0 4.0 5.0 6.0 7.0 8.0 0.1 0.5 1.0 1.5 2.0 4.0 5.0 6.0 7.0 8.0

ln(qe-qt) = −0.1304t + 1.0011 ln(qe-qt) = −0.3467t + 2.1599 ln(qe-qt) = −0.4516t + 2.6227 ln(qe-qt) = −0.7245t + 2.8557 ln(qe-qt) = −0.3729t + 3.4975 ln(qe-qt) = −0.9521t + 3.6102 ln(qe-qt) = −0.4428t + 3.5998 ln(qe-qt) = −0.5343t + 3.4470 ln(qe-qt) = −0.5418t + 3.8242 t/qt = 0.8769t + 0.1682 t/qt = 0.2334t+ 0.0511 t/qt = 0.115t + 0.1197 t/qt = 0.0741t + 0.0581 t/qt = 0.0571t + 0.0172 t/qt = 0.0297t + 0.0264 t/qt = 0.0277t + 0.0057 t/qt = 0.0261t + 0.0142 t/qt = 0.0249t + 0.0088 t/qt = 0.0229t + 0.0176

R2 2

R R2 R2 R2 R2 R2 R2 R2 R2 R2 R2 R2 R2 R2 R2 R2 R2 R2 R2

= = = = = = = = = = = = = = = = = = =

model

0.9959 0.9822 0.9734 0.9982 0.9992 0.9974 0.9854 0.8813 0.9753 0.9996 0.9995 0.9947 0.9968 0.9996 0.9972 0.9998 0.9987 0.9997 0.9983

intraparticle diffusion model

Elovich model

C (wt %)

correlation

0.1 0.5 1.0 1.5 2.0 4.0 5.0 6.0 7.0 8.0 0.1 0.5 1.0 1.5 2.0 4.0 5.0 6.0 7.0 8.0

0.5

qt qt qt qt qt qt qt qt qt qt qt qt qt qt qt qt qt qt qt qt

= = = = = = = = = = = = = = = = = = = =

0.1129(t ) + 0.6129 0.4305(t0.5) + 2.2650 1.1046(t0.5) + 3.0269 1.6541(t0.5) + 5.1497 1.8706(t0.5) + 8.5173 4.2719(t0.5) + 11.7251 3.6436(t0.5) + 18.9280 4.4905(t0.5) + 16.0511 4.2240(t0.5) + 19.3631 5.4377(t0.5) + 15.7882 0.1899 ln(t) + 0.6105 0.7283 ln(t) + 2.2487 1.9415 ln(t) + 2.8656 2.8918 ln(t) + 4.9333 3.1524 ln(t) + 8.4659 7.4032 ln(t) + 11.2741 6.0578 ln(t) + 18.9632 7.7024 ln(t) + 15.7070 6.8563 ln(t) + 19.6781 9.3182 ln(t) + 15.3852

R2 2

R R2 R2 R2 R2 R2 R2 R2 R2 R2 R2 R2 R2 R2 R2 R2 R2 R2 R2 R2

= = = = = = = = = = = = = = = = = = = =

0.3707 0.3743 0.5176 0.5061 0.4547 0.5698 0.4167 0.5042 0.4992 0.5923 0.4251 0.4344 0.6484 0.6274 0.5238 0.6941 0.4671 0.6016 0.5335 0.7027

Figure 11. Intraparticle diffusion plot for surfactant adsorption onto carbonate rock: a) surfactant concentration, wt% [0.5, 2.0, 4.0, 5.0, 8.0] and b) surfactant concentration, wt% [0.1,1.0, 1.5, 6.0, 7.0]. Figure 10. Pseudo-second order plot for surfactant adsorption onto carbonate rock: a) surfactant concentration, wt% [0.1,0.5, 1.0, 1.5, 2.0] and b) surfactant concentration, wt% [4.0, 5.0, 6.0, 7.0, 8.0].

and ln(t) over the whole adsorption course with low coefficients of determination (R2 ≪ 1) for all of the lines (Table 3). The constant parameters obtained from the Elovich kinetic model are listed in Table 3 for the surfactant/carbonate system. Clearly, both α and β constants are functions of the initial surfactant concentration, Co. Figure 12 and Table 3 demonstrate a weak correlation between the experimental

Using the adsorption data, a plot of the Elovich kinetic model for the surfactant is presented in Figure 12. In this case, there is a linear correlation between Glycyrrhiza Glabra adsorbed, qt, 9901

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Figure 13. Adsorption behavior of Glycyrrhiza Glabra at different temperatures based on the Langmuir isotherm model.

temperature increases, the adsorption capacity of this surfactant decreases. Thus, the adsorption process is exothermic. When physisorption of gases or liquids over solids occurs, the amount of adsorption will increase by increase in pressure. This is because the adsorbate volume reduces during adsorption process. It should be noted here that the effect of pressure is much stronger in gas adsorption cases compared with liquid adsorption systems. The current study was conducted at the atmospheric pressure. Investigating the effect of pressure on the parameters and adsorption kinetics is part of our future research work. 5.5. Glycyrrhiza Glabra versus Common Surfactants. There are some main differences between the newly introduced surfactant and common surfactants available in the market as follows: • The price of surfactants such as alkyl poly glycosides and alkyl sulfates that are commonly employed in oil industry varies between 3.0 and 5.0 US$ per kilogram; while Glycyrrhiza Glabra, a new nonionic surfactant, can be obtained around 1.5−2.0 US$/kg in Middle Eastern countries such as Iran and Egypt. Hence, Glycyrrhiza Glabra is very inexpensive. • Glycyrrhiza Glabra is natural, biodegradable and thus more environmentally friendly compared to common artificial surfactants in petroleum industry. • A surfactant loss between 3 and 8 mg/g of rock in the absence of oil is common as reported in petroleum literature.5−10 The adsorption value of Glycyrrhiza Glabra at CMC point was found to be 4 mg/g. This is on the lower range of other known surfactants. • In comparison with the common surfactants examined, Glycyrrhiza Glabra is shown to more favorably reduce interfacial tension (IFT). Lower IFT may be achieved using Glycyrrhiza Glabra, leading to greater pore scale recovery. The change of interfacial tension with surfactant concentration in the presence of kerosene oil is depicted in Figure 14. It should be noted here that IFT is determined by the drop-weight method in this study. The reduction percentage of IFT is around 69% when Glycyrrhiza Glabra is employed, compared to 52% and 41% for alkyl poly glycosides and alkyl sulfates surfactants, respectively. 5.6. Cost and Environmental Aspects. For a surfactant flood, it is vital to take into account both technical and

Figure 12. Elovich model plot for surfactant adsorption onto carbonate rock: a) surfactant concentration, wt% [0.1,1.0, 2.0, 5.0, 7.0] and b) surfactant concentration, wt% [0.5,1.5, 4.0, 6.0, 8.0].

adsorption data and the theoretical data calculated by the Elovich kinetic model as defined by eq 13. Hence, the Elovich equation should not be used to predict the adsorption kinetics behavior of Glycyrrhiza Glabra onto the carbonate samples. 5.4. Adsorption Thermodynamic. The Gibbs free energy change (ΔGo) is an important thermodynamic parameter when determining the spontaneity of a process. An adsorption reaction takes place spontaneously at a particular temperature if ΔGo has a negative value.6,36 Knowing the Langmuir isotherm model suitably describes the adsorption system, the free energy change of adsorption is given as follows6,36

ΔGo = −RT ln Kad

(15)

where T and Kad represent the absolute temperature (K) and Langmuir constant, respectively. R is the universal gas constant that equals 8.314 J mol/K in the above equation. ΔGo has the unit of J/mol, here. The magnitude of ΔGo for sorption of the surfactant was found to be −13.96 kJ/mol according to eq 15. The negative value of the free energy change (ΔGo) validates possibility and spontaneous nature of the adsorption process. Temperature plays an important role in the adsorption of surfactant on carbonate samples. The temperature has two main impacts on the adsorption process. First, an increase in temperature will lower the rate of adsorbate diffusion across the external boundary layer and in the interior pores of the carbonate particles because the solution viscosity declines as temperature increases. Second, the temperature affects the equilibrium capacity of the carbonate samples depending on whether the adsorption process is exothermic or endothermic. Figure 13 shows the adsorption of Glycyrrhiza Glabra at four temperatures (27 °C, 60 °C, 75 °C, and 150 °C). As the 9902

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2

3

Figure 14. Interfacial tension versus surfactant concentration for three different surfactants.

4

economic factors. The economic viability is essentially dependent on parameters such as the cost of surface-active substance and the oil price. The surfactant is normally the most costly part in the EOR surfactant flooding scheme.1−4 Surfactant expenses consist of purchasing the surfactant at the start of the project and also the cost for surfactant replacement diminished during the adsorption process.1−4 Glycyrrhiza Glabra is a natural surface-active substance found in oil-producing countries such as Iran. It is inexpensive and easily available; thus the question of cost does not come up for this new introduced surfactant. In addition, this natural compound is considered as an environmentally friendly surfactant that causes minimal or no harm to the environment. 5.7. Potential EOR Application of Glycyrrhiza Glabra. The key purposes of surfactant flooding method in fractured carbonate reservoirs are wettability alteration and interfacial tension (IFT) reduction, leading to enhancing the imbibition process.1−10 Surfactant injection as a chemical stimulation process has been examined in carbonate porous media such as Cottonwood Creek and Yates Fields in the USA.5,9,32−36 These oilfields were operated under depletion previously. As the pressure declined, free gas produced and quickly escaped via the fractures to form a gas cap. Some EOR methods such as surfactant injection and thermal assisted gravity segration in pilot plant scales are ongoing to increase oil production from these oil reservoirs.5,9,32−36 In addition, there are underway Alkali-Surfactant-Polymer (ASP) and Surfactant−Polymer (SP) projects in both carbonate and sandstone formations such as Delaware Childers Field (Oklahoma), Lawrence Field (Illinois), Nowata Field (Oklahoma), and Grayburg Carbonate Formation (Texas), based on the EOR review by Moritis (2008).1−10,32−36,73 Therefore, this new surfactant can have EOR applications in chemical flooding for sandstone and carbonate oil reservoirs in North America.

5 6



that for an aqueous system without carbonate. This is attributed to attraction forces between the negatively charged Glycyrrhiza Glabra and the positively charged carbonate. With increase in the surfactant concentration, the adsorption on the carbonate surface increases until the saturation point. To predict the saturation condition, a suitable adsorption model was proposed for this particular surfactant. The linear and Freundlich and Temkin equilibrium adsorption models are not suitable for predicting the surfactant/carbonate adsorption; however, there is a good agreement between the experimental data and the model results with R2 = 0.9964 while using the Langmuir adsorption isotherm. Pseudo-second order kinetic model can satisfactorily estimate the kinetics of surfactant adsorption on the carbonate rock. The adsorption mechanism is expected to be quite complex for the surfactant/carbonate system and perhaps is a combination of diffusion and external mass transfer. The adsorption process is exothermic as amount adsorbed decreases with increasing temperature. Availability and the reasonable cost of the Glycyrrhiza Glabra make it economically viable for surfactant flooding. Moreover, the newly introduced surfactant poses less risk to the environment.

AUTHOR INFORMATION

Corresponding Author

*Phone: 519-888-4567 ext. 36157. E-mail: szendehb@ uwaterloo.ca. Notes

The authors declare no competing financial interest.



ACKNOWLEDGMENTS The first author would like to acknowledge the Petroleum University of Technology (PUT) for providing financial support throughout this research.



NOMENCLATURE

Acronyms

CMC EOR HMC NFCR OOIP PPM SDDBS XRD

Critical Micelle Concentration Enhanced Oil Recovery Hemimicellar Concentration Naturally Fractured Carbonate Reservoir oil originally in place part per million sodium alkyl benzene sulfonate X-Ray Diffraction

Variables

B

6. CONCLUSIONS The adsorption of Glycyrrhiza Glabra onto crushed carbonates was systematically investigated in this paper. Equilibrium and kinetic behaviors of the surfactant were discussed in detail, and adsorption parameters for the Langmuir, Freundlich, linear, and Temkin isotherms were determined. The following conclusions can be drawn based on the results of this study: 1 The adsorption of surfactant onto carbonate causes the dose to achieve micellization being much greater than

C Ce Co h K1 K2 9903

Temkin constant which is related to the heat of adsorption surfactant concentration in aqueous solution after equilibrium, (ppm) and (mg/L) equilibrium concentration, (ppm) and (mg/L) surfactant concentration in the initial solution before equilibrium, (ppm) and (mg/L) initial kinetics rate, (mg/g) pseudo-first order rate constant, (min−1) pseudo-second order adsorption rate constant, (g/ mg·min) dx.doi.org/10.1021/ie300269c | Ind. Eng. Chem. Res. 2012, 51, 9894−9905

Industrial & Engineering Chemistry Research Kad Kf KH Kt mcarbonate msolution n q qe qo R t T t1/2 ΔG°

Article

(14) Webb, K. J.; Black, C. J. J.; Tjetland, G. A. Laboratory Study Investigating Methods for Improving Oil Recovery in Carbonates. IPTC-10506, International Petroleum Technology Conference, Doha, Qatar, 21−23 November 2005. (15) Haugen, Å.; Fernø, M. A.; Graue, A. Numerical Simulation and Sensitivity Analysis of In-situ Fluid Flow in MRI Laboratory Waterfloods of Fractured Carbonate Rocks at Different Wettabilities. SPE-116145, SPE Annual Technical Conference and Exhibition, Denver, CO, USA, 21−24 September 2008. (16) Delshad, M.; Najafabadi, N. F.; Sepehrnoori, K. Scale-up Methodology for Wettability Modification in Fractured Carbonates. SPE-118915, SPE Reservoir Simulation Symposium, Woodlands, TX, USA, 2−4 February 2009. (17) Mohanty, K. K. Dilute Surfactant Methods for Carbonate Formations: Final Report; Report no. DE-FC26-02NT 15322; U.S. Department of Energy: Washington, DC, USA, February 2006. (18) Adibhatia, B.; Mohanty, K. K. Simulation of Surfactant-Aided Gravity Drainage in Fractured Carbonates. SPE-106601, SPE Reservoir Simulation Symposium, Houston, TX, USA, 26−28 February 2007. (19) Al-Dhafeeri, A. M.; Nasr-El-Din, H. A.; Al-Mubarak, H. K.; AlGhamdi, J. Gas Shut-off Treatment in Oil Carbonate Reservoirs in Saudi Arabia. SPE-114323, SPE Annual Technical Conference and Exhibition, Denver, CO, USA, 21−24 September 2008. (20) Kumar, A.; Al-Ajmi, M. F.; Al-Anzi, E.; Clark, R. A.; Khater, M.; Lantz, J. Water Shut off Techniques to Combat Premature Water Breakthrough in Mauddud Carbonate ReservoirAn Efficacy Analysis. IPTC-11713, International Petroleum Technology Conference, Dubai, UAE, 4−6 December 2007. (21) Al-Taq, A. A.; Nasr-El-Din, H. A.; Beresky, J. K.; Naimi, K. M.; Sierra, L.; Eoff, L. Simultaneous Acid Diversion and Water Control in Carbonate Reservoirs: A Case History from Saudi Arabia. SPE-106951, SPE Reservoir Eval. Eng. 2008, 11, 882−891. (22) Smith, D. D.; Giraud, M. J.; Kemp, C. C.; McBee, M.; Taitano, J. A.; Winfield, M. S.; Portwood, J. T.; Everett, D. M. The Successful Evolution of Anton Irish Conformance Efforts. SPE-103044, SPE Annual Technical Conference and Exhibition, San Antonio, TX, USA, 24−27 September 2006. (23) Portwood, J. T. The Kansas Arbuckle Formation: Performance Evaluation and Lessons Learned from More than 200 Polymer-Gel Water-Shutoff Treatments. SPE-94096, SPE Production Operations Symposium, Oklahoma City, OK, USA, 16−19 April 2005. (24) Sengupta, T. K.; Singh, R.; Avtar, R.; Singh, K. Successful Gas Shut Off Using Latest Gel Technology in an Indian Offshore Carbonate FieldA Case Study. SPE-72118, SPE Asia Pacif ic Improved Oil Recovery Conference, Kuala Lumpur, Malaysia, 6−9 October 2001. (25) Hirasaki, G. J.; Miller, C. A.; Pope, G. A. Surfactant Based Enhanced Oil Recovery and Foam Mobility Control3rd Annual & Final Technical Report; Report No. DE-FC26-03NT15406; Rice University and U.S. Department of Energy: Houston, TX, USA, July 2006. (26) Freer, E. M.; Svitova, T.; Radke, C. J. The Role of Interfacial Rheology in Reservoir Mixed Wettability. J. Pet. Sci. Eng. 2003, 39, 137−158. (27) Buckley, J. S. Effective Wettability of Minerals Exposed to Crude Oil. Curr. Opin. Colloid Interface Sci. 2001, 6, 191−196. (28) Morrow, N. R. Wettability and its Effect on Oil Recovery. J. Pet. Technol. 1990, 42, 1476−1484. (29) Buckley, J. S.; Liu, Y. Some Mechanisms of Crude Oil/Brine/ Solid Interactions. J. Pet. Sci. Eng. 1998, 20, 155−160. (30) Hassenkam, T.; Pedersen, C. S.; Dalby, K.; Austad, T.; Stipp, S. L. S. Pore Scale Observation of Low Salinity Effects on Outcrop and Oil Reservoir Sandstone. Colloids Surf., A 2011, 390, 179−188. (31) Moritis, G. EOR Continues to Unlock Oil Resources-Report on Enhanced Oil Recovery. Oil Gas J., 12 April 2004a. (32) Levine, S.; Sigmon, R.; Douglas, S. Yates FieldSuper Giant of the Permian Basin. Houston Geol. Soc. Bull. 2002, 45 (3), 39−45. (33) Moritis, G. Report on Enhanced Oil Recovery. Oil Gas J., 15 April 2000.

energy of adsorption, (L/mg) Freundlich constant constant in linear model, (L/m2) equilibrium binding constant at maximum binding energy, (L/mg) total mass of crushed carbonate, (g) total mass of solution in original bulk solution, (g) Freundlich constant adsorption capacity, (mg/g-rock) equilibrium adsorption, (mg/g-rock) adsorption capacity in Langmuir model, (mg/g-rock) universal gas constant, (J/mol·K) time, (h) and (day) temperature, (K) half-adsorption time, (h) Gibbs free energy change, (kJ/mol)

Greek letters

α initial adsorption rate for the Elovich model, (mg/g·min) β adsorption constant for the Elovich model, (mg/g·min) Subscript

ad e f o



adsorption equilibrium Freundlich maximum capacity of adsorption

REFERENCES

(1) Worldwide EOR Survey, Oil Gas J. 1996, Vol. 94(16), pp 45−61. (2) Worldwide EOR Survey, Oil Gas J. 2004, Vol. 102(14), pp 53− 65. (3) Worldwide EOR Survey, Oil Gas J. 2006, Vol. 104(15), pp 45− 57. (4) Special Report: EOR/Heavy Oil Survey: 2010 worldwide EOR survey. Oil Gas J., 2010, Vol. 108(14). (5) Xie, X.; Weiss, W. W.; Tong, Z.; Morrow, N. R. Improved Oil Recovery from Carbonate Reservoirs by Chemical Stimulation. SPE J. 2005, 10 (3), 276−285. (6) Seethepalli, A.; Adibhatla, B.; Mohanty, K. K. Physiochemical Interactions during Surfactant Flooding of Carbonate Reservoirs. SPE J. 2004, 9 (4), 411−418. (7) Thomas, M. M.; Clouse, J. A.; Longo, J. M. Adsorption of Organic Compounds on Carbonate Minerals: 1- Model Compounds and their Influence on Mineral Wettability. Chem. Geol. 1993a, 109 (1−4), 201−213. (8) Thomas, M. M.; Clouse, J. A.; Longo, J. M. Adsorption of Organic Compounds on Carbonate Minerals. 3. Influence on Dissolution Rates. Chem. Geol. 1993b, 109 (1−4), 227−237. (9) Yang, H. D.; Wadleigh, E. E. Dilute Surfactant IORDesign Improvement for Massive, Fractured Carbonate Applications. SPE 59009, SPE International Petroleum Conference and Exhibition, Villahermosa, Mexico, 1−3 February 2000. (10) Chen, H. L.; Lucas, L. R.; Nogaret, L. A. D.; Yang, H. D.; Kenyon, D. E. Laboratory Monitoring of Surfactant Imbibition with Computerized Tomography. SPE Reservoir Eval. Eng. 2001, 4 (1), 16−25. (11) Manrique, E. J.; Muci, V. E.; Gurfinkel, M. E. EOR Field Experiences in Carbonate Reservoirs in the United States. SPE Reservoir Eval. Eng. 2007, 10, 667−686. (12) Najafabadi, N. F.; Delshad, M.; Sepehrnoori, K.; Nguyen, Q. P.; Zhang, J. Chemical Flooding of Fractured Carbonates Using Wettability Modifiers. SPE-113369, SPE/DOE Symposium on Improved Oil Recovery, Tulsa, OK, USA, 20−23 April 2008. (13) Tabary, R.; Fornari, A.; Bazin, B.; Bourbiaux, B.; Dalmazzone, C. Improved Oil Recovery with Chemicals in Fractured Carbonate Formations. SPE-121668, SPE International Symposium on Oilf ield Chemistry, Woodlands, TX, USA, 20−22 April 2009. 9904

dx.doi.org/10.1021/ie300269c | Ind. Eng. Chem. Res. 2012, 51, 9894−9905

Industrial & Engineering Chemistry Research

Article

(34) Moritis, G. Report on Enhanced Oil Recovery. Oil Gas J., 15 April 2002. (35) Allan, J.; Qing Sun, S. Controls on Recovery Factor in Fractured Reservoirs: Lessons Learned From 100 Fractured Fields. SPE 84590, SPE Annual Technical Conference and Exhibition, Denver, USA, 5−8 October 2003. (36) Schramm, L. L. Surfactants: Fundamentals and Applications in the Petroleum Industry; United Kingdom, 2000. (37) Kwok, W.; Hayes, R. E.; Nasr-El-Din, H. A. Modeling Dynamic Adsorption of an Anionic Surfactant on Berea Sandstone with Radial Flow. Chem. Eng. Sci. 1995, 50, 769−783. (38) Curbelo, F. D. S.; Santanna, V. C.; Barros Neto, E. L.; Dutra, T. V., Jr.; Dantas, T. N. C.; Dantas Neto, A. A.; Garnica, A. I. C. Adsorption of Nonionic Surfactants in Sandstones. Colloids Surf., A 2007, 293, 1−4. (39) Sheng, J. J. Modern Chemical Enhanced Oil Recovery: Theory and Practice. Elsevier Inc.: 2011; ISBN: 978-1-85617-745-0. (40) Ottewill, R. H.; Tadros, T. F. Introduction to Surfactants; Academic Press: London, 1984; pp 1−18. (41) Prevot, A. B.; Gulmini, M.; Zelano, V.; Pramauro, E. MicrowaveAssisted Extraction of Polycyclic Aromatic Hydrocarbons from Marine Sediments Using Nonionic Surfactant Solutions. Anal. Chem. 2001, 73, 3790−3795. (42) Bezerra, M. A.; Arruda, M. A. Z.; Ferreira, S. L. C. Cloud Point Extraction as a Procedure of Separation and Pre-Concentration for Metal Determination Using Spectra-Analytical Techniques: A Review. Appl. Spectrosc. Rev. 2005, 40, 269−299. (43) Prevot, A. B.; Gulmini, M.; Zelano, V.; Pramauro, E. MicrowaveAssisted Extraction of Polycyclic Aromatic Hydrocarbons from Marine Sediments Using Nonionic Surfactant Solutions. Anal. Chem. 2001, 73, 3790−3795. (44) Pelizzetti, E.; Pramauro, E. Analytical Applications of Organized Molecular Assemblies. Anal. Chim. Acta 1985, 169, 1−29. (45) Pino, V.; Ayala, J. H.; Afonso, A. M.; Gonzalez, V. Determination of Polycyclic Aromatic Hydrocarbons in Marine Sediments by High-Performance Liquid Chromatography after Microwave-Assisted Extraction with Micellar Media. J. Chromatogr., A 2000, 869, 515−522. (46) Pino, V.; Ayala, J. H.; Afonso, A. M.; Gonzalez, V. Cloud-point Pre-concentration and HPLC Determination of Polycyclic Aromatic Hydrocarbons in Marine Sediments. Anal. Bioanal. Chem. 2001, 371, 526−531. (47) Hinze, W. L.; Singh, H. N.; Fu, Z.; Williams, R. W.; Kippenberger, D. J.; Morris, M. D.; Sadek, F. S. Chemical Analysis of Polycyclic Aromatic Compounds; Wiley: New York, 1989; p 151. (48) Yeom, I. T.; Ghosh, M. M.; Cox, C. D.; Robinson, K. G. Micellar Solubilization of Polynuclear Aromatic Hydrocarbons in Coal Tar-Contaminated Soils. Soils Environ. Sci. Technol. 1995, 29, 3015− 3021. (49) Leja, J. Surface Chemistry of Froth Flotation; Plenum: New York, 1982; Vol. 1. (50) Stumm, W. Aquatic Chemistry; Wiley: New York, 1970; Vol. 2, Chapter 3. (51) Meader, A. C. Adsorption in the Detergent Process. Ind. Eng. Chem., July 1952, pp 1636−1648. (52) Gaudin, A. M.; Fuerstenau, D. W. Quartz Flotation with Cationic Collectors. Trans. AIME 1955, 202, 958−962. (53) Somasundaran, P.; Fuerstenau, D. W. Mechanisms of Alkyl Sulfonate Adsorption at the Alumina-Water Interface. J. Phys. Chem. 1966, 70, 90−96. (54) Paria, S.; Khilar, K. C. A Review on Experimental Studies of Surfactant Adsorption at the Hydrophilic Solid-Water Interface. Adv. Colloid Interface Sci. 2004, 110, 75−95. (55) Zhang, R.; Somasundaran, P. Advances in Adsorption of Surfactant and their Mixtures at Solid/Solution Interfaces. Adv. Colloid Interface Sci. 2006, 123−126, 213−229. (56) Ayranci, E.; Duman, O. Removal of Anionic Surfactants from Aqueous Solutions by Adsorption onto High Area Activated Carbon

Cloth Studied by In-Situ UV Spectroscopy. J. Hazard. Mater. 2007, 148, 75−82. (57) Wayman, C. H. Surfactant Sorption on Heterionic Clay Minerals. Intern. Clay Conf., Stockholm 1963, 1, 329−350. (58) Scamehorn, J. F. Equilibrium Adsorption of Surfactants on Mineral Oxide Surfaces from Aqueous Solutions. Ph.D. Dissertation, University of Texas at Austin, 1980. (59) Trogus, F. J.; Schechter, R. S.; Wade, W. H. A New Interpretation of Adsorption Maxima and Minima. J. Colloid Interface Sci. 1979, 70 (2), 293−305. (60) Gogoi, S. B. Adsorption of Non-Petroleum Base Surfactant on Reservoir Rocks. Curr. Sci. 2009, 97, 1059−1063. (61) Kjellim, M.; Johansson, I. Surfactants from Renewable Resources; John Wiley & Sons, Ltd. Publication: 2010; p 242. (62) Hostettmann, K.; Marston, A. Saponins; Cambridge University Press: New York, 1995. (63) Guglu-Ustundag, O.; Mazza, G. Saponins: Properties, Applications and Processing. Crit. Rev. Food Sci. Nutr. 2007, 47, 231−258. (64) Stanimirova, R.; K. Marinova, S.; Tcholakova, N. D. Surface Rheology of Saponin Adsorption Layers. Langmuir 2011, 27 (20), 12486−12498. (65) Langmuir, I. The Constitution and Fundamental Properties of Solids and Liquids: Part I. solids. J. Am. Chem. Soc. 1916, 38, 2221− 2295. (66) Rosen, M. J. Surfactants and Interfacial Phenomena; John Wiley & Sons, Inc.: 1989; pp 3363−3374. (67) Freundlich, H. M. F. Ü ber die adsorption in lösungen. Z. Phys. Chem. 1906, 57 (A), 385−470. (68) Temkin, M.; Pyzhev, V. Recent Modifications to Langmuir Isotherms. Acta Physiochim. USSR 1940, 12, 217−222. (69) Ruthven, D. M. Principles of Adsorption and Adsorption Processes; Wiley Inter-science; New York, 1982. (70) Lagergren, S. Zur theorie der sogenannten adsorption gelöster stoffe, Kungliga Svenska Vetenskapsakademiens. Handlingar 1898, 24 (4), 1−39. (71) Mckay, G.; Ho, Y. S. Pseudo-Second Order Model for Sorption Processes. Process Biochem. 1999, 34, 451−465. (72) Low, M. J. D. Kinetics of Chemisorptions of Gases on Solids. Chem. Rev. 1960, 60, 267−317. (73) Moritis, G. Worldwide EOR Survey. Oil Gas J. 2008, 106, 41− 42, 44−59.

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dx.doi.org/10.1021/ie300269c | Ind. Eng. Chem. Res. 2012, 51, 9894−9905