Papers by Keyword: Surfactant

Abstract: Clays modified with quaternary ammonium salts, organoclays, have an affinity for organic compounds undergoing expansion. In this study, the smectite clay Chocolate" A" was subjected to the process of organophilization with quaternary ammoniumchloride, stearyl dimethyl ammonium chloride (Praepagen WB) to improve its hydrophobic properties and thus increase the affinity for organic compounds. The samples were characterized by X ray diffraction (XRD), infrared spectroscopy and tests of expansion by swelling of Foster. The results showed appropriate conditions organophilization process. Through XRD confirmed the increase in basal spacing for the clay modified with respect to the clay in natural, 15.46Å to 19.99Å after treatment with the quaternary ammonium salt. Bands of the CH₃ and CH₂ were detected by infrared spectroscopy analysis of the sample and the organoclay according to the tests of expansion was possible to observe the affinity of the organoclay with organic compounds: gasoline, kerosene and diesel.

Abstract: A preparation of a kind of green water-based metal cleaning agent has been described in this paper. The reaction is using oleic acid and triethanolamine, by add the corresponding surface active agent. After a series of performance test, all kinds of metal has good corrosion resistance and cleaning effect, and no pollution to the environment.

Abstract: Quaternary ammonium cationic surfactants have very important application in the papermaking industry, which is a series of important paper softening agents. In order to obtain an environment-friendly paper softening agent, a novel diester gemini quaternary ammonium salt cationic surfactant has been prepared. Dodecyldimethyl amine, epichlorohydrin and adipic acid were used as raw materials to synthesize the surfactant, and Fourier transform infrared spectroscopy was used to characterize the groups in reaction product. Moreover, the softening effect of the diester gemini quaternary ammonium salt cationic surfactant was studied in detail.

Abstract: The influence of Zwitterionic - propanesulfonate surfactant on the surface properties such as surface roughness, surface morphology and microhardness of Ni-B coatings using electroless alkaline bath was reported in this paper. Ni-B deposits obtained from nickel chloride as the source of nickel and borohydride as the reducing agent at a pH of 11 and 12 and temperature 85 ± 2 ^OC. This study reveals that the Ni – B coatings were clearly influenced by the addition of surfactant propanesulfonate on surface roughness and surface morphology. Electroless nickel (EN) - B coatings with addition of surfactant has changed the surface morphology from non-smooth nodular appearance to a smooth surface with average roughness value 1.4μm, which is less than the R_a value of without surfactant 1.98μm. The hardness of the deposit increased with lesser concentration of the surfactant when compared to without surfactant addition. Surface morphology and composition of the Ni–B coatings was analyzed by scanning electron microscope (SEM) and X-ray diffraction (XRD).

Abstract: The addition of additives to the water is known to enhance boiling heat transfer. In the present investigation, boiling heat transfer coefficients are measured for Nichrome wire, immersed in saturated water with & without additive. An additive used is 2-Ethyl 1-Hexanol with varying concentrations in the range of 10-10000 ppm. Extensive experimentation of pool boiling is carried out above the critical heat flux. Boiling behavior i.e. bubble dynamics are observed at higher heat flux for nucleate boiling of water over wide ranges of concentration of additive in water. Results are encouraging and show that a small amount of surface active additive makes the nucleate boiling heat transfer coefficient considerably higher, and that there is an optimum additive (500-1000ppm) concentration for higher heat fluxes. An optimum level of enhancement is observed up to a certain amount of additive 500-1000ppm in the tested range. Thereafter significant enhancement is not observed. This enhancement may be due to change in thermo-physical properties i.e. mainly due to a reduction in surface tension of water in the presence of additive.

Abstract: A novel smart gel based on interpenetrating network of anionic polymer and surfactant was investigated. A supramolecular assembly structured gel is formed by associating polymer side chain with wormlike micelle of surfactant. The physical interaction of val der vaal and hydrogen bonding force between surfactant and polymer gives a strong viscoelastic gel at evaluated temperature. The viscoelastic properties and gel structure were characterized by dynamic rheometer and cryo-TEM. The polymer and VES complex gel is highly elastic, which elastic moduli G’ is higher than loss moduli G’’ at low angular frequency, 0.1 rad/s, in high temperature. The total concentration of surfactant and polymer is low which is economically to use in industries.

Abstract: This paper shows the results obtained from the synthesis of silver particles (nanoparticles and submicroparticles) on microfiltration membranes, evaluating the influence of surfactants impregnated in the membranes. Sub-micro particles and nanoparticles were obtained by the use of ascorbic acid as a reductant in a microfiltration system. Different shapes and sizes of the deposited silver particles on the membrane were obtained depending on the nature and concentration of the surfactant. The particles deposited over the membranes were characterized by scanning electron microscopy and energy- dispersive X-ray analysis.

Abstract: Although supercritical CO₂ fracturing has incomparable advantages compared to hydraulic fracturing as a new recreating technology of shale gas reservoir, the application of this technology has been limited by the low viscosity and weak carrying capacity of proppant. It’s critical to enhance the viscosity of supercritical CO₂ by adding thickening agents. Thickening agents for supercritical CO₂ that have been studied by researchers mainly contained polymers, small molecular compounds and surfactants. Thickening agents that match with CO₂ are characterized by low cohesive energy density, low polarity, high free volume and Lewis base. It’s necessary to study the interaction between thickening agents and CO₂ by molecular simulation to design inexpensive, green thickening agents which could increase the viscosity of supercritical CO₂ remarkably under low concentration.

Abstract: This work focused on the analysis of static forces of a Cu particle in CO₂-based micelle solutions with different surfactant, including fluorinated surfactants PFPE COO^-NH₄⁺, 8FS(EO)₂ and hydrocarbon surfactants L31, DiF₈-PO₄^-Na⁺. Calculations demonstrated that high pressure could impose enough capillary pressure effect beneath a particle to compete with the net adhesion force and increase the particle surface separation distance. The ESD for the micelle solutions had the similar behavior, otherwise, the value of NAF for the micelle solution with surfactant DiF₈-PO₄^-Na⁺ had the minimum relative to other surfactant micelle solutions, suggesting that Cu particles would be more easily removed in micelle solution with DiF₈-PO₄^-Na⁺ surfactant.

Abstract: Corrosion and scaling are the common problems to all the industries. A remedy of these problems was sought out through chemical treatment: indigenously available raw materials including thiourea, surfactants (cationic, anionic and nonionic containing pre, critical and post micellar concentration). Evaluation of corrosion inhibition properties stainless steel 316 by thiourea based inhibitor and its synergistic effect with cationic cetyl tri-methyl ammonium bromide (CTAB), anionic sodium dodecyl sulphate (SDS) and nonionic triton X-100 have been carried out by weight loss method as a function of concentration of thiourea and surfactants. These materials were applied to the coupons of stainless steel 316 in different acidic concentration. Corrosion rates were calculated using weight loss method. Excellent results were achieved regarding corrosion inhibition in the presence of thiourea and surfactants assuring the better performance of these chemicals. The results showed that corrosion rate was decreased from 90 mpy to 12.1 mpy after 720 hours by the addition of 200ppm thiourea in critical micellar concentration of SDS in 3M HCl acid solution.