Influence Of Sodium Dodecyl Sulfate Research Articles

Imbibition behavior of water on coal surface and the impact of surfactant

Coal seam water injection is vital in mitigating dust pollution in coal mining operations. To investigate water imbibition and adsorption behavior on the coal surface following injection into coal seams, as well as the impact of surfactants, coal particles with sizes of 6–8 mm, 3–5 mm, and 0.4–0.85 mm were selected from the Dongtan Coal Mine in Shandong Province, China. Coal particle imbibition experiments were designed for coal particles at varying surfactant concentrations and temperatures, and molecular simulation was employed to examine the micro adsorption behavior of water within coal rock pores. The findings indicate that smaller coal particles exhibit significantly higher water absorption capacity compared to larger particles when ample water supply is present. This suggests that coal pore water absorption is inherently limited. Moreover, elevated formation temperatures hinder the wetting process of water injection. Importantly, introducing surfactants leads to the blockage of coal fractures, constriction of fracture channels, and restriction of the effective wetting range of coal seam water. Furthermore, the influence of sodium dodecyl sulfate is greater than that of cetyltrimethylammonium bromide. In low-temperature environments, surfactants exert a more prominent inhibitory effect on water injection wetting. These research findings provide valuable theoretical guidance for coal seam dust prevention efforts and water injection technology.

A method to determine two antibiotics prescribed to treat nosocomial infections in plasma and urine by micellar liquid chromatography

Combined prescription of the antimicrobial drugs linezolid and meropenem is a common strategy to treat multidrug-resistant nosocomial infections. We propose an innovative method to determine these two drugs in plasma and urine, based on micellar liquid chromatography. Both biological fluids were diluted in mobile phase, filtered and directly injected, without any extraction step. Using a C18 column and a mobile phase of 0.1 M sodium dodecyl sulfate – 10 % methanol, phosphate buffered at pH 3, running under isocratic mode, both antibiotics were eluted without overlapping in<15 min. Detection was by absorbance: 255 nm for linezolid and 310 nm for meropenem. The influence of sodium dodecyl sulfate and methanol concentration on retention factor was established for both drugs using an interpretative approach assisted by chemometrics. The procedure was successfully validated following the guidelines of 2018 Bioanalytical Method Validation Guidance for Industry in terms of: linearity (determination coefficients over 0.99990), calibration range (1 – 50 mg/L), instrumental and method sensitivity, trueness (bias of −10.8 to + 2.4%), precision (relative standard deviation of < 10.2%), dilution integrity, carry-over effect, robustness and stability. It should be emphasized that the method uses low volumes of toxic and volatile solvents and can be achieved in a short period. The procedure was found useful for routine analysis, as it was cost-affordable, more eco-friendly and safer than hydroorganic HPLC, easy-to-handle and highly sample-throughput. Finally, it was applied to incurred samples of patients taking this medication.

Influence of sodium dodecyl sulphate on the surface and rheological behaviour of functionalised silica/polyacrylamide for drilling

AbstractThe stability of polymer composite can be enhanced by altering the structure of the functionalised material with surface modifiers, such as silane coupling agents, organic modifiers, surfactants and others. Surfactant has emerged as a potential modifier since it is eco‐friendly and simple. In this study, the surface of functionalised silica (SiO2) was modified using sodium dodecyl sulphate (SDS) in a polyacrylamide (PAM) composite. Characterisation of the drilling fluid was examined through Fourier‐transform infrared spectroscopy, surface tension, contact angle and rheological tests. According to the results, FTIR proved that the modification of PAM was successful. However, all modified PAM showed more hydrophilic properties with low surface tension than bare PAM. The rheological properties of all the modified PAM were varied over all the concentrations of SDS. Meanwhile, the rheological properties of the modified PAM were better than that of bare PAM. Due to the synergistic effect between the surfactant and functionalised material involved, the drilling fluid achieved low plastic viscosity in modified PAM. With a flat gel strength and better rheological properties, 0.2 wt% SDS in modified PAM is a great and promising formula in this study. In the future, further investigation can be conducted on bored pile drilling using this formulation.

Influence of SDS concentration on the formation of carbon dioxide hydrate in a colloidal solution of water + SDS + SiO2

The paper presents a study of the formation of gas hydrate in a colloidal solution of water + SDS + SiO2. The influence of sodium dodecyl sulfate (SDS) on the process of the kinetic promoter at various concentrations: 0, 100, 300, 500 ppm was studied. The process itself is described, the dependences of temperature and pressure changes on time for each case are presented. The conversions of gas and solution to the hydrate state are determined. Carbon dioxide was used as the hydrate-forming gas.

Effect of sodium dodecyl sulfate on shape‐memory properties of side‐chain crystalline hydrogel via micellar copolymerization

AbstractA chemical shape‐memory hydrogel containing crystalline structure is prepared via micellar copolymerization of hydrophilic monomer acrylamide (AM) and hydrophobic monomer octadecyl acrylate (C18) in a sodium dodecyl sulfate (SDS) solution. The influence of SDS on the shape‐memory behavior of hydrogel investigated by differential scanning calorimetry (DSC) and Temperature‐dependent X‐ray indicate that the melting and crystallization peaks derived from the thermal properties of C18 units is different from peaks corresponding to the pure SDS. In addition, the microstructure evolution information of hydrogels dose not change upon heating process, regardless of the presence or absence of SDS. Therefore, only the hydrophobic associations formed by C18 blocks play a decisive role in the shape memory function of hydrogel system. The difference between the transition process (from temporary shape to permanent shape) of hydrogel with and without SDS at different temperature is because that the hydrophobic region of side chain crystallization of SDS‐free hydrogel may escape the restriction of SDS and become more sensitive to temperature, they can preferentially return to their initial shape under the same time and temperature than SDS‐containing gels. Whether SDS exists only affect the speed of shape memory behavior, but not the microstructure evolution of hydrogel system.

Passivation of corrosion product layer on AM50 Mg by corrosion inhibitor

The influence of sodium dodecyl sulfate (SDS) on morphology and chemical composition of corrosion product layer formed on α-Mg matrix and cathodic Al-Mn intermetallic was systematically investigated by using FIB and TEM analysis for the first time to disclose the underlying inhibition mechanism. A porous corrosion bi-layer composed of crystalline MgO and Mg(OH) 2 was observed on both of α-Mg and Al-Mn intermetallic. It was found that a passive inner layer was deposited on α-Mg after immersion in SDS-containing NaCl solution, which can be ascribed to steady-state growth of magnesium and aluminum oxide under the protection of hydrophobic group of SDS. The inhibition mechanism of the inhibitor was mainly associated with formation of dense oxide layer on α-Mg matrix and preferential adsorption of SDS on the corrosion layer deposited on Al-Mn intermetallic.

Circular Dichroism Spectra of α-Chymotrypsin-SDS Solutions Depend on the Procedure of Their Preparation.

We recorded the far- and near-UV circular dichroism (CD) spectra of solutions of α-chymotrypsin and sodium dodecyl sulfate (SDS) with the final surfactant concentration significantly above the critical micellization concentration. Solutions were prepared using three different procedures. The reference procedure was to mix the chymotrypsin solution with the SDS solution once, immediately achieving the final SDS concentration. In alternative procedures, the protein solutions initially contained some SDS and were mixed with pure SDS solutions at a concentration to provide the same final surfactant as the reference mixing. We demonstrate that the supplementation to the selected final concentration of SDS of the pure chymotrypsin solution leads to different CD spectra than the supplementation to this final concentration of SDS in the chymotrypsin solution containing a small concentration of a few millimolar SDS. These differences disappear when the initial concentration of SDS in the protein solution, which we then supplement to the indicated final concentration, is higher. This suggests the irreversibility of the processes caused by the addition of SDS to chymotrypsin and the influence of the initial amount of this surfactant on the processes occurring with its further addition to the solution. For quantitative analysis of far-UV CD spectra in terms of populations of protein secondary structure elements, we used four well-established software packages. All programs consistently indicate that the observed differences in the far-UV CD spectra can be explained by the differences in the increase in the population of helical forms in chymotrypsin under the influence of SDS.

Experimental and Molecular Dynamics Simulation Study for Preferring Coal Dust Wetting Agents.

To improve the efficiency of coal dust removal by water spray technology, the addition of wetting agents in water becomes the main dust removal method. The influence of sodium dodecyl sulfate (SDS), sodium dodecyl sulfonate (SDDS), and sodium dodecylbenzene sulfonate (SDBS) on the wettability of coal dust is studied by experimental and molecular dynamics (MD) simulation. Measurement of the contact angle and surface tension was accomplished via relevant experiments for the three wetting agents, and their adhesion work, spreading work, and wetting work were also calculated. A preferred experimental method of conventional coal dust wetting agent is optimized. The wettability of the three wetting agents upon bituminous coal follows the trend: SDS > SDDS > SDBS. The simulation was performed based on MD to derive the intermolecular interaction energy, diffusion coefficient of water molecules, and water molecule count in the vicinity of the hydrophilic groups of the wetting agents. The wetting mechanism and performance of the wetting agent solution on bituminous coal were identified. The simulation results of the wetting performance of the wetting agents are consistent with the experimental results, which verifies the reliability of the simulation method. An easy, time-saving, and labor-saving MD simulation method is proposed, which provides a novel insight for choosing various wetting agents of coal dust.

Storage capacities of CO2 hydrates in packed silica bed in multiple formation processes

Hydrate-based gas storage is known to be an economical and eco-friendly method. In this work, the growth of CO2 hydrate was repeated 5 times in the silica gels with certain water saturation at an initial pressure of 3.7 MPa, 278.15 K. The influence of sodium dodecyl sulfate (SDS) and water saturation ranging from 30 to 60% on CO2 storage efficiency was measured. Results showed that silica gels with 30% water saturation got the highest CO2 storage capacity with the water conversion of 91% within 24 h and did not have evident decay in repeated tests. The volume ratio of adsorbed CO2 to silica gels was found to decrease from 46 to 19 as the initial water saturation increased from 30 to 60%. In repeated runs, the volume ratio descended evidently in the initial 3 runs. Water film covered on the silica gel particles was assumed to be the major obstacle for hydrate growth. SDS was found to enhance the volume ratio in the silica gel with high water saturations and reduce the decay of volume ratio in repeated test. However, the unexpected long hydrate nucleation period ranging from 5 to 8 h would occur after 3 repeated test. SEM images revealed that the hydrate crystals attached with each other like pomegranate seeds in pure water system, while they changed into flakes which adhere on the silica gel particles. Neither of these morphologies provide a path for CO2 diffusion. Therefore, avoiding the formation water film on silica gel particles and increasing the porosity of the porous particles are the key to improve gas storage efficiency.

Effect of the Concentration and the Type of Dispersant on the Synthesis of Copper Oxide Nanoparticles and Their Potential Antimicrobial Applications.

The bactericidal properties of copper oxide nanoparticles have growing interest due to potential application in the medical area. The present research investigates the influence of sodium dodecyl sulfate (SDS) and poly(vinylpyrrolidone) (PVP) on the production of copper oxide nanoparticles prepared from copper sulfate (CuSO4) and sodium borohydride (NaBH4) solutions. Different analytical techniques were used to determine the crystal nature, mean size diameter, and surface morphology of the copper oxide nanoparticles. The X-ray diffraction (XRD) patterns showed formation of nanoparticles of cuprite (Cu2O) and tenorite (CuO) when PVP and SDS were added at the beginning of the reaction. In fact, when the Cu/PVP ratio was 1.62, Cu2O nanoparticles were obtained. In addition, nanoparticles of CuO were synthesized when the Cu/PVP ratios were 0.54 and 0.81. On the other hand, a mixture of copper oxides (CuO and Cu2O) and cuprite (Cu2O) was obtained when PVP (Cu/PVP = 0.81 and 1.62) and SDS (Cu/SDS = 0.90) were added 30 min after the beginning of the reaction. Transmission electron microscopy (TEM) images show agglomerated nanoparticles with a size distribution ranging from 2 to 60 nm, while individual particles have sizes between 4.1 ± 1.9 and 41.6 ± 12.8 nm. The Kirby–Bauer method for the determination of antibacterial activity shows that small CuO (4.1 ± 1.9 nm) and Cu2O (8.5 ± 5.3 nm) nanoparticles inhibit the growth of Escherichia coli, Staphylococcus aureusMRSA, S. aureus and Pseudomonas aeruginosa bacteria. The antibacterial test of cotton fabric impregnated with nanoparticles shows positive results. The determination of the optimal ratio of copper oxide nanoparticles per cm2 of fabric that are able to exhibit a good antibacterial activity is ongoing.

Sodium dodecyl sulfate improves the properties of bio-based wood adhesive derived from micronized starch: Microstructure and rheological behaviors

Enhancing the performance of starch-based wood adhesive is vitally important for its practical applications. Accordingly, we designed the use of micronized starch (MS) to prepare micronized starch-based wood adhesive (MSWA) by incorporating 0, 2, 4 and 6% (w/w, dry basis starch) sodium dodecyl sulfate (SDS). The results showed that 2% SDS exhibited remarkable improvement in shear strength and viscosity of MSWA. The grafted reaction was demonstrated by 1H NMR and the steady shear results indicated that the adhesive possessed a pseudoplastic behavior under yield stress conditions. Besides, dynamic rheological measurements were applied to evaluate the structure of MSWA under varying frequencies, temperatures and constant stain. The transmission electron microscopy (TEM), Zeta potential and surface tension indicated that SDS could improve the surficial properties. Meanwhile, the microstructure of adhesive films and fracture surfaces of glued wood veneers by scanning electron microscopy (SEM) demonstrated that the migration of SDS led to the formation of surfactant layer. Furthermore, element analysis revealed the distribution of S/N in latex slices. The results of this study provide the detailed information about the influence of SDS on the rheological properties and microstructures of MSWA, which may facilitate the preparation of high performance bio-based adhesive for wood applications.

Development of low pressure reverse osmosis membrane for desalination process

Water shortage has become a real problem at global level and therefore, new and innovative technologies were established to provide sustainable solutions to water crisis. One of the effective approaches to resolve the global challenges is introducing the membrane-based desalination. Reverse Osmosis (RO) is a pressure driven membrane process which becoming increasingly popular and widely used for water purification applications that require high salt rejection such as brackish and seawater desalination. In this study, the influence of Sodium dodecyl sulphate (SDS) surfactant in producing the finest membrane for desalination were investigated in terms of performance, morphological structure and molecular orientation. From a polymer blending of polysulfone (PSF)/N-Methyl-2-Pyrrolidone (NMP)/polyvinylpyrrolidone (PVP)/sodium dodecyl sulphate (SDS) were formulated for making of low pressure reverse osmosis (LPRO) membrane. In order to examine the influence of SDS surfactant, different concentration from 0 wt% to 3 wt% were employed for desalination application of 10,000ppm (brackish water) and 50 000ppm (seawater). Experimental data showed that the increasing of 0.5wt% in surfactant produced higher pure water permeation (PWP) and flux. At 2.5wt% of SDS, the LPRO membranes showed the highest PWP of about 44.8L/m2h and brackish water flux at 45.58L/m2h. Meanwhile, at 3.0wt%, the highest flux of seawater at 39.37L/m2h was obtained. Moreover, the optimized LPRO (2wt% of SDS) membrane performed high rejection ratio of 90.9% for brackish water and 90.4% for seawater concentration of 10,000ppm and 50,000ppm, respectively. Therefore, the findings revealed that the fabricated LPRO membrane having a good potential to be used as eco-efficient desalination process of brackish water and seawater technology.

Influence of sodium dodecyl sulfate as a surfactant on the microstructural, morphological and optoelectronic characteristics of SILAR deposited CuO thin films

The research was performed aiming to evaluate the impact of sodium dodecyl sulfate (SDS) as a surfactant on the morphological, microstructural, electrical and optical features of nanostructured cupric oxide (CuO) thin films. CuO thin films were grown using successive ionic layer adsorption and reaction (SILAR) technique at room temperature. These as-prepared CuO thin films were thoroughly characterized by scanning electron microscope (SEM), x-ray diffraction (XRD), four-point probe method, UV-Visible spectrophotometer and Fourier transform infrared (FTIR). Surface morphology investigations revealed the uniform and homogeneously distributed CuO nanostructures on the film surfaces. The addition of different concentration of SDS to the growth solution significantly influenced the surface morphological characteristics of the CuO thin films. XRD analysis showed that all deposited CuO thin films were polycrystalline nature having monoclinic crystal system and presented () and (111) preferential orientations. The microstructural parameters, including crystallite size, texture coefficient, microstrain and dislocation density were extracted from XRD data. The resistivity value of CuO thin film prepared without SDS was 1.72 × 106 Ω cm. With SDS concentration of 4.0 M%, the resistivity extraordinarily increased to 3400 × 106 Ω cm. The optical bandgap energy had increased from 1.32 to 1.49 eV as a function of increasing SDS concentration. The CuO bond vibration was confirmed by FTIR analysis.

Influence of Sodium Dodecyl Sulfate on the Microstructure and Electrochromic Performance of an Electrodeposited Nickel Oxide Film

Nickel oxide (NiO) films were deposited on indium tin oxide (ITO) coated glass substrates using a potentiostatic electrodeposition method from Ni(NO3)2 aqueous solution containing the surfactant sodium dodecyl sulfate (SDS). The microstructure, morphology, and electrochromic performance of the NiO films were investigated. Our results showed that the addition of SDS inhibited the growth of NiO crystals, tailored the morphology of the films, and favoured their electrochromic performance. The NiO films deposited in the presence of 6mM SDS exhibited excellent electrochromic performance in OH− containing electrolytes (0.1M KOH), with a high optical contrast of over 77% at 550nm, short switching time (5.62s for bleaching and 7.34s for coloration), and enhanced cycling durability.

Study the influence of sodium dodecyl sulfate on emulsification of heavy and waxy crude oils to improve their flow ability in low temperature conditions

AbstractTransportation of heavy and waxy crude oils through pipelines is a problem in many regions of the world where low temperatures are observed usually in offshore conditions due to wax and asphaltene precipitation. Transporting them as oil‐in‐water (O/W) emulsion through pipelines is one of the feasible flow assurance solutions. In this research work, O/W emulsions using anionic surfactant sodium dodecyl sulfate are prepared for two Indian crude oil samples having significant asphaltene and wax deposition potential and effect of emulsification on the flow properties of these crude oils are thoroughly analyzed. It is found that the prepared emulsions have very stable phase volume composition up to 50 days at ambient conditions, and they are thermally stable in the temperature range 20–45°C. Emulsions of heavy crude oil are found to be relatively more stable than that of waxy crude with time and temperatures. Fifty percent (v/v) is the observed optimized oil content in the prepared o/w emulsions for both the crude oils at optimum surfactant concentration that is critical micelle concentration (CMC). The prepared emulsions have viscosities as low as 0.01 Pa s and pour point as low as less than 0°C, ensuring easy flow at low temperatures, suited for pipeline transportation at subsea conditions. Interfacial tension and surface tension values of waxy crude‐water system and its o/w emulsions respectively are higher than that of heavy crude‐water system and its O/W emulsions, which indicate difficulty in waxy crude oil transportation compared with heavy crude oil.

Effect of Surfactants on Pressure Drop in Vertical Water-Air and Gas Condensate-Air Two-Phase Vertical Flow

The influence of Sodium dodecyl sulfate and Triton X-100 surfactants on the two-phase pressure drop and two phase flow regime of water-air and gas condensate-air in upward vertical pipe were investigated for various gas/liquid flow rates. Sodium dodecyl sulfate and Triton X-100 reduced the pressure drop of single phase water flow by 11% and 29% compared with that of pure water single phase flow at water velocity of 13 m/s. For condensate single phase flow, Sodium dodecyl sulfate and Triton X-100 reduced the pressure drop by 9% and 17% compared with that of condensate single phase flow with no surfactant at gas condensate velocity of 13 m/s. The maximum efficiency of Sodium dodecyl sulfate and Triton X-100 in reducing the pressure drop of water-air system were 67.1% and 79.8%, respectively, compared with that of pure water-air two-phase flow. For gas condensate-air system, the maximum efficiency of Sodium dodecyl sulfate and Triton X-100 in reducing the pressure drop was 57.1% and 36.7%, respectively, compared to that of pure condensate-air two-phase flow.

Ultrasonic-Assisted Fabrication of Concentrated Triglyceride Nanoemulsions and Nanogels.

In many food products such as gels, pastes, jellies, creams, sausages, and selected dressings or spreads, it is desirable to formulate concentrated triglyceride nanoemulsions so as to deliver lipophilic functional agents. In this study, the ability of ultrasonication to form nanoemulsions and nanogels containing high concentration of sunflower oil was investigated in the presence of sodium dodecyl sulfate (SDS) as a surfactant. The influence of SDS and oil concentration and duration of sonication on the physical stability, mean droplet diameter, and rheological properties of emulsions were determined. Ultrasonication for up to 9 min was highly effective on fabrication of stable nanoemulsions (an average droplet size of 158-171 nm) at low oil/surfactant ratio (10:0.7). The viscosity and storage modulus increased with decreasing the droplet size particularly at higher oil concentrations. The viscous nanoemulsions (containing 60, 50, and 40 wt % oil) transformed into viscoelastic gels when sonicated for 3, 9, and 30 min, respectively. On the basis of the findings of the present study, such textural and rheological modifications, resulted from droplet size decreasing, could be potentially useful in designing reduced fat gel-like products.

Influence of sodium dodecyl sulphate on the surface morphology and infrared emissivity of porous Ni film

The purpose of this study is to investigate the effect of sodium dodecyl sulphate (SDS) concentration on the surface morphology as well as infrared emissivity of porous Ni film prepared through the method of dynamic hydrogen bubble template (DHBT). The results indicate that the addition of SDS can enhance the hydrogen evolution reaction and increase the volume of evolving hydrogen bubbles during electrodeposition process, resulting in the increase of pore density, depth and diameter of Ni film. These factors affect the roughness greatly and the relationship between roughness and infrared emissivity has been inferred. A wide range of infrared emissivity (0.36–0.80) of porous Ni film was obtained through control of the concentration of SDS. It is concluded that the addition of SDS has a significant effect on the improvement of roughness of the porous Ni film and is beneficial for the film to obtaining high thermal emission.

Synergistic effect of sodium dodecyl sulfate and salts on the gelation properties of acid-hydrolyzed-hydroxypropylated potato starch

Appropriate modifications of starch are necessary to meet the industrial demand for high-quality hard capsule materials as an alternative to gelatin. In the present study, the influence of sodium dodecyl sulfate (SDS) and salts on the gelation properties of acid-hydrolyzed-hydroxypropylated potato starch (AHP) was characterized using dynamic rheological tests. A significant phenomenon was discovered in terms of a synergistic effect between SDS and salts, and was further explored using blue-value and zeta-potential analyses. In particular, the gelation temperature of the AHP pastes increased with increasing concentrations of KCl until there was not enough SDS available to achieve a cooperative effect. Formation of a starch-SDS inclusion complex led to a weakened combination of starch-iodine, and increased the surface charge of starch molecules. Moreover, a decrease in zeta-potential value was observed along with the addition of KCl. Considering the charged sulfate groups of complex starch-SDS, which was provided by SDS, were similar to that of carrageenan, we put forward a hypothesis that the observed synergistic effect of SDS and salts is mainly attributed to the electronic interactions between salt ions. The current study provides a necessary strategy for applying AHP as a gelatin alternative in the manufacturing of hard capsules.

Influence of sodium dodecyl sulfate on the kinetics and control of RAFT/MADIX polymerization of acrylamide

ABSTRACTAqueous radical polymerizations of acrylamide were conducted in the presence of varying concentrations of sodium dodecyl sulfate (SDS) and two xanthate reversible addition‐fragmentation chain transfer (RAFT) agents: the small, hydrophobic Rhodixan A1 and the oligomeric, amphiphilic PAm7‐XA1. The presence of SDS led to significant retardation of the polymerization, while the apparent activity of both RAFT/MADIX agents decreased as the SDS concentration increased. PAm7‐XA1 was affected to a lesser degree than Rhodixan A1, probably due to its lesser tendency to become sequestered in SDS micelles. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 760–765