Papers by Keyword: Surfactant

Abstract: Foam flooding is a promising enhanced oil recovery (EOR) while improving the gas sweep efficiency problem of gas flooding. On the other hand, nanotechnology has paved the way for utilizing nanoparticles in surfactant foam while improving foam stability, lamella thickness, bubble size distribution, and oil recovery. The significant difference between nanoparticles and surfactants as foam stabilizers is the adsorption energy of nanoparticles at gas-liquid interfaces, which is thousands of times bigger than surfactants. However, previous studies on nanoparticles' foam adsorption energy are limited by using only nanoparticles (in the absence of surfactants), though it is hard to generate foam since it does not reduce surface tension significantly. Thus, the objective of this study is to determine the adsorption energy of hydrophilic silicon dioxide (SiO2) and partially hydrophobic silicon dioxide (PH SiO2) nanoparticles in the presence of anionic sodium dodecyl sulfate (SDS) and cationic cetyltrimethylammonium bromide (CTAB) surfactants. Another objective is to analyze and evaluate the effects of adsorption energy on foam stability. Consequently, the particle radius, surface tension, and particle surface wettability were all obtained from the maker, Du Noüy ring tensiometer, and particle surface contact angle. The result shows that the adsorption energy of PH SiO2 was a thousand times greater than hydrophilic SiO2 in the presence or absence of surfactants. Due to PH SiO2 having a slightly bigger particle radius, higher adsorption energy in the PH SiO2 system is mainly by particle hydrophobicity and surface tension. In all systems, the highest adsorption energy is achieved at the lowest concentration of nanoparticles because the increment in nanoparticle concentration reduces the surface tension, eventually lowering the adsorption energy. However, this trend is contradicted with half-life foam stability when it increases with the nanoparticles concentration until the optimum concentration is obtained, then reduced. To sum up, the evaluation of the nanoparticles' foam adsorption energy in this study supports the fundamentals of nanoparticles stabilizing foam that are also influenced by other parameters: the maximum capillary pressure, particle arrangements during film drainage, and growing aggregate and the ‘cork’ formation inside lamella.

Abstract: The use of hybrid nanofluids aimed to improve the exceptional qualities of fluids, including adsorption, viscosity, stability, and interfacial tension. Although several surfactant changes utilizing hybrid nanomaterials have been documented, their wider application has been hindered by the material's stability and processing challenges. The purpose of this study is to use the liquid phase exfoliation technique and examine the properties of the recently created hybrid nanofluids. This paper investigates the mechanisms of how hybrid nanofluids (HNF) composed of Graphene nanoplatelet (GNP) & SiO₂ with various surfactants such as Gum Arabic (GA) and Sodium Carboxymethyl Cellulose (SCMC) could improve EOR through adsorption of nanoparticles, improve viscosity, Interfacial tension (IFT), and wettability contact angle. Based on the results, using the hybrid nanoparticles decreases the IFT between oil-water interface from 39.700 mN/m for brine to 38.466, 37.582, 35.609 mN/m, for Control HNF, GA HNF, and SCMC HNF respectively. The adsorption of nanoparticles mechanism occurs and peaks during a 12-hour to 24hour period. Furthermore, the findings on the performance of hybrid nanofluid have increased the viscosity from 0.317cP (brine) to 3.638cP (GA) and 3.556cP (SCMC) nanofluid. When nanoparticles are introduced into reservoirs, they interact with rocks and crude oil via rock absorption, potentially improving the recovery rate of oil by changing wettability and influencing the efficiency of water-transfer to oil in several improved oil recovery methods. The contact between the rock surface, nanofluid, and oil was shown to be reduced by 29.47% and 59.12%, as seen by the contact angle of the oil droplet on the rock surfaces. The phenomenon occurs because nanoparticles are attached to the interface of rock, oil, and brine.

Abstract: This study indicated the characterization of irradiated detergent by using Bovine serum albumin (BSA). Detergent act as cleaning agents in our daily life. However, most of synthetic detergent which contain anionic surfactant are non-biodegradable and contributed to the environmental issue and also give negative effect on human health. Bovine serum albumin (BSA) are used in this study as the function of protein that contribute for the growth and activities of the biological systems. Bovine serum albumin (BSA) have 76% of similarity with human serum albumin in our body. To overcome this issue, detergent production based on green concept prospective and chemical substances reduction are produced. This detergent are produced from three combinations of vegetables oil which is sunflower oil, palm oil and corn oil as triglycerides in soap production. This study are compared with brand X synthetic detergent with the interaction of BSA. The chemical properties and surface morphology for both detergent with BSA sample have been characterized using ultraviolet-visible (UV-Vis) spectroscopy, Fourier transform infrared (FTIR) spectroscopy and Opto-Digital microscope. The results shows that the UV-Vis absorption spectra of the irradiated detergent sample have degraded some of functional group and reduce the emulsion absorption. Meanwhile, the observation for both sample by using FTIR shows the synthetic detergent has the higher number of carbon which decrease the biodegradable ratio. As conclusion, the production of detergent with three combination vegetables oil are more biodegradable and the radiation effect give significant function for detergent degradation.

Abstract: Nanotechnology has been the prime approach over the last several decades including in scaling prevention. There has been a flurry of activity in incorporating nanoparticles (NPs) with scale inhibitors (SI) to help mitigate the scales’ growth at the early stage before it worsens. However, despite the increasing use of nanoparticles in industry, reservoir complexity such as salinity and heterogeneity have significantly impacted the nanoparticles' performance in the medium. The nanoparticles' repulsive forces are reduced when brine salinity is present, resulting in flocculation and coagulation of nanoparticles in suspension and phase separation. However, the stability and dispersion of nanoparticles may be improved by altering their characteristics by coating them with a surfactant for a particular application. This can be done by introducing a surfactant in the nanoparticle suspension. Herein, this paper aims to study the dispersion and stability of different types of NPs and their performance in Sodium Dodecyl Sulfate (SDS) surfactant solution. Results obtained proved that carbon-based NPs (graphene oxide (GO) and multi-walled carbon nanotube (MWCNT)) showed an excellent zeta potential measurement up to -116 mV when these NPs were dispersed in SDS solution. This surfactant has significantly improved the NPs stability by increasing electrostatic repulsion between the NPs while reducing the average size of agglomeration.

Abstract: This study explores the impact of epoxidized palm oil (EPO) content and surfactant type on the mechanical properties of polyurethane foams. The resilience, hardness, and compressive strength of the foams were systematically analyzed at different NCO/OH molar ratios. The findings revealed that increasing EPO content generally decreased both hardness and resilience values, indicating enhanced viscoelastic properties due to the plasticizing effect of EPO's hydrocarbon chains. However, specific surfactants significantly influenced these mechanical properties. Concentrol STB PU-2254 and Tegostab® B82001 VE surfactants enhanced compressive strength by promoting a compact cellular structure with smaller, more numerous cells, effectively distributing loads and counteracting the softening effect of high EPO content. Conversely, the use of Tegostab® B8462 resulted in reduced hardness due to increased porosity from larger cell formation. At an NCO/OH ratio of 1.0, higher pMDI content improved compressive strength by increasing hard segment formation. These results underscore the importance of surfactant selection and NCO/OH ratio optimization in tailoring the mechanical properties of polyurethane foams, offering valuable insights for their application-specific design and optimization.

Abstract: Nanoparticles' unique properties, such as their huge surface area, higher thermal conductivity, and increased dielectric strength, make them appealing candidates for high voltage insulation applications. The choice of a suitable surfactant is critical in the creation of nanofluids. The ratio of hydrophilic to lipophilic (HLB) values, which ratio up the hydrophilic and lipophilic structure of the surfactant, is normally considered in the selection of suitable surfactant for the nanofluid. Surfactant with HLB value less than 6 is said to be more suitable for oil base nanofluids. Recent research, however, indicated that the sediment generated by high and low HLB value surfactants is not significantly different. Tween 20 surfactant, while rarely used in this context due to its high HLB value, is an intriguing option due to its affordable cost and excellent properties. Its distinct features, such as low toxicity, and strong emulsification capacity, make it an appealing candidate for stabilizing and dispersing nanoparticles in nanofluid compositions. In this research, tween 20 was used in the preparation of palm oil (PO) and palm fatty acid ester oil (PFAE) based nanofluids. Iron (II,III) Oxide (Fe₃O₄) nanoparticle was introduced to the nanofluids at high, medium and low concentrations. The nanofluids were evaluated in terms of its breakdown strength and dielectric properties. The alternating current (AC) breakdown and dielectric properties were conducted based on the IEC 60156 and ASTM D924 Standard respectively. Tween 20 has positive impact on shortening down the sonication period by 10 % and 33.3 % for PO and PFAE based nanofluids, respectively, while elongating the sedimentation period for PO nanofluids. The breakdown voltage improved by 40% and 18% for PO based nanofluid and PFAE based nanofluid, respectively. Even at low concentrations, the inclusion of Fe₃O₄ nanoparticles improved breakdown strength, and breakdown voltage distributions offered useful information. The addition of nanoparticles slightly increases the relative permittivity of the base oils. Fe₃O₄ nanoparticle and tween 20 surfactant has successfully improved the dielectric loss of the base oil with the lowest value recorded at 0.05 g/L, with 72.4 % and 36.8 % improvement for PO and PFAE based nanofluids, respectively. These results proved that tween 20 is suitable for oil-based nanofluids applications.

Abstract: Graphene oxide (GO) exhibits a wide range of outstanding mechanical, electrical, and physical characteristics, and it is of substantial interest to impart such qualities onto polymeric materials such as poly (methyl methacrylate) PMMA for wider specialized functionalization. The attention of this work is on the development of emulsion polymerization procedure to prepare PMMA-GO nanocomposite and the effect of sodium dodecyl sulphate (SDS) surfactant dosages incorporated during the polymerization, on the effect of PMMA surface interactions in oil. The grafting efficiency is quantified using the Fourier-transform infrared spectroscopy (FTIR), and the effect of surfactant concentration on PMMA-GO stability is examined using UV-Visible spectroscopy, zeta potential and particle size analyses using the Malvern Zetasizer. The surfactant free emulsion has a better stabilization in terms of zeta potential analysis compared to emulsion of PMMA-GO with 0.32, and 0.4 wt. % of SDS. The polymerized PMMA-GO can be used as a model system to alter wax crystallization at low temperatures in oil and gas industries.

Abstract: The aim of this study was to improve the stability and rheological properties of water-in-oil-in-water (W/O/W) multiple emulsions containing 30 wt% paraffin oil, and 4 wt% polyglycerol-3-polycinoleate (PGPR) as a lipophilic surfactant. This was done by adding different concentrations of xanthan gum (GX) and the hydrophilic surfactants (Polyoxyethylene (80) sorbitan monooleate (Tween® 80), poloxamer 407(Lutrol® F127) using the emulsification in a two-steps process. The stability of the W/O/W multiple emulsions was analyzed over one-month storage period using physicochemical and rheological measurements. An excellent structure appeared with 0.175 wt% of xanthan gum in the outer aqueous phase and 1 wt% of Tween® 80. The modified Cross model was successfully applied to fit the flow curves of multiple W/O/W emulsions at different concentrations of xanthan gum. The incorporation of xanthan gum in a concentration range of 0.05-0.175 wt% induced an increase in the yield stress, in the zero-shear rate viscosity, and in the infinite shear rate viscosity of the multiple emulsions. The study also showed that adding xanthan gum in a concentration range of 0.05-0.175 wt% to W/O/W emulsions caused an increase in the viscosity of the system in the Newtonian regime and viscoelastic behavior.

Abstract: The stability of dispersed nanoparticles in the base fluid has always been one of the most important challenges in using nanofluids as a coolant in heat transfer applications in different industries such as modern electronic equipment, heat exchangers, solar technologies, etc. In the present study, the dynamic light scattering (DLS) method is used to obtain the particle size distribution of Al₂O₃-ZnO dispersed in DI water. After adjusting the optical arrangement and designing the DLS setup, the correlation curves are plotted by analyzing the detected signals of the experiments. Then, a decay rate is derived by fitting an exponential function to the correlation curve to get the particle size distribution by using the Stoke-Einstein equation. In order to investigate the stability of Al₂O₃-ZnO water-based nanofluid, the particle size distribution profiles are studied several times. In addition, the stability of Al₂O₃-ZnO-CNT hybrid nanofluid is followed by absorbance measurements using a UV-Vis spectrophotometer. Moreover, the thermal conductivity coefficient and electrical conductivity of the Al₂O₃-ZnO hybrid nanofluid with and without CNT particles are determined by utilizing KD2 Pro and PCT-407 devices, respectively. The results showed that the peak in the particle size distribution curve for Al₂O₃-ZnO hybrid nanofluid shifted from 476 nm to 128 nm after 5 days. Furthermore, the inclusion of carbon nanotubes increased the stability of zinc oxide particles in the nanofluid. In addition, by adding carbon nanotubes in a ratio of 1:1:0.5 to Al₂O₃-ZnO nanofluid and forming 0.05 wt.% hybrid nanofluid, the thermal conductivity coefficient was enhanced by 30% in comparison with deionized water, while a 0.05 wt.% hybrid nanofluid without CNT particles improved the thermal conductivity by 19%. Although the electrical conductivity increased by adding nanoparticles to the base fluid, it didn’t change significantly for nanofluids containing CNTs compared to nanofluids without CNT particles.

Abstract: Fenton process involving Fe²⁺ ions and H₂O₂ produces OH radicals, that act as a strong oxidizing agent for degradation of a variety of organic pollutants. However the process is poor performance at neutral pH limiting its application for industrial wastewater treatment. The short coming problem, in the current study, is solved by introducing ethylene diamine tetra acetic acid (EDTA) as a complexing compound. The degradation was conducted through batch experiment, by varying EDTA concentration and pH. In addition, the Fe²⁺ and H₂O₂ concentrations, and the reaction time were optimized. The research results assign that the addition of EDTA could remarkably enhance the degradation of anionic surfactant, that was 96% at pH 6-8. The increase of the degradation was proportional to the concentrations of EDTA and 6 mg/L showed the optimum level. The highest degradation of 162 mg/L anionic surfactant in 20 mL of the laundry wastewater could be achieved within 30 mins by using Fe²⁺ 10 mM, H₂O₂ 50 mM, and in the pre12sence of EDTA 6 mg/L at pH 7. Key words : Fenton, EDTA, degradation, surfactant, wastewater