Mineral Oil In Water Research Articles

Emulsions Stabilized with an Electrostatic Complex of Quaternized Cellulose Nanofiber and Octanoyl Gelatin and the Effect of pH Value on Their Stability

Oil/water (O/W) emulsions were prepared using the complex of quarternized cellulose nanofiber (QCNF) and octanoyl gelatin (OC−Gel) as an emulsifier, and the effect of pH value on their stability was investigated. OC−Gel was prepared through a condensation reaction, confirmed by 1H Nuclear Magnetic Resonance (NMR) and Fourier Transform Infrared (FT−IR) spectroscopy. It reduced air/water interfacial tension more effectively than unmodified gelatin. The complexation degree of OC−Gel and QCNF, measured by optical density, showed its maximum at a QCNF/OC−Gel mass ratio of 1/8 when the pH value of the medium was 7.4, and it increased in a saturated manner with increasing pH value. The signals of QCNF were found in the FT−IR and X−ray diffraction spectra of the complex, suggesting that the positively charged CNF were included in the OC−Gel−based complex. The complex formed a rough surface with smooth debris because the surface roughness of the complex aggregation reflected that of both QCNF and OC−Gel aggregation. QCNF could stabilize oil droplets to form a Pickering O/W emulsion. The complex of QCNF/OC−Gel was also a good emulsifier. QCNF and the complex were as potent as OC−Gel in emulsifying mineral oil in water. Most of the droplets fell within 5–25 µm, regardless of what the emulsifier was. The emulsion stabilized with OC−Gel increased in its oil droplet size more than two times in 20 days at all the pH vales tested (pH 3, 5, 7.4, 9), whereas the emulsion stabilized with QCNF remained almost constant in size during the same period regardless of the pH values. The droplet size of emulsion stabilized with the QCNF/OC−Gel complex did not change appreciably when the pH value was 5, 7.4, and 9. The complex seemed to act as a capsule wall and prevent the coalescence of the droplets. However, it increased dramatically due to the coalescence at pH 3, possibly because the complex could be dissolved under a strong acidic condition.

Silica Nanoparticles in Xanthan Gum Solutions: Oil Recovery Efficiency in Core Flooding Tests.

Polymer flooding is one of the enhanced oil recovery (EOR) methods that increase the macroscopic efficiency of the flooding process and enhanced crude oil recovery. In this study, the effect of silica nanoparticles (NP-SiO2) in xanthan gum (XG) solutions was investigated through the analysis of efficiency in core flooding tests. First, the viscosity profiles of two polymer solutions, XG biopolymer and synthetic hydrolyzed polyacrylamide (HPAM) polymer, were characterized individually through rheological measurements, with and without salt (NaCl). Both polymer solutions were found suitable for oil recovery at limited temperatures and salinities. Then, nanofluids composed of XG and dispersed NP-SiO2 were studied through rheological tests. The addition of nanoparticles was shown to produce a slight effect on the viscosity of the fluids, which was more remarkable over time. Interfacial tension tests were measured in water-mineral oil systems, without finding an effect on the interfacial properties with the addition of polymer or nanoparticles in the aqueous phase. Finally, three core flooding experiments were conducted using sandstone core plugs and mineral oil. The polymers solutions (XG and HPAM) with 3% NaCl recovered 6.6% and 7.5% of the residual oil from the core, respectively. In contrast, the nanofluid formulation recovered about 13% of the residual oil, which was almost double that of the original XG solution. The nanofluid was therefore more effective at boosting oil recovery in the sandstone core.

6-acylamino nicotinic acid-based hydrogelators applicable in phase selective gelation, reproducible mat formation and toxic dye removal

Formation of nanofibers and nanovesicles in the self-assembled state of small amphiphilic molecules has applications in versatile fields such as tissue engineering, controlled delivery of drug molecules, etc. This paper demonstrated the self-aggregation behavior of three synthesized 6-acylamino nicotinic acid amphiphiles named 6-octanoylamino-nicotinic acid (OANA), 6-decanoylamino-nicotinic acid (DANA) and 6-dodecanoylamino-nicotinic acid (DDANA) in water and basic aqueous solution. The result showed that the amphiphiles successfully self-organize into vesicles and twisted ribbons in water. FT-IR study revealed existence of mixtures of handedness in the fibrous structures. CD spectroscopy and TEM study elucidated formation of chiral structures through aggregation. Results showed that DDANA forms thermoreversible hydrogel in aqueous solutions of NaOH and Na2CO3, whereas other two amphiphiles form hydrogel only in the presence of NaOH. Morphological investigation revealed that the hydrogel is formed due to self-assembly of fibrils of micron length. The elastic fibrillar networks are quite stable to external forces. Existence of bilayer columnar square packing arrangement in the self-assembled state was recognized by XRD measurement. Spectroscopy and theoretical studies established that hydrogen bonding interactions are responsible to self-assemble the amphiphilic molecules. The amphiphiles are efficient phase selective gelators of mineral oils in water–mineral oil mixtures and excellent remover of rhodamine 6G, eosin Y and rose bengal from water. The amphiphiles successfully create reproducible fiber mat applicable in tissue engineering field.

Study on the concentration of mineral oil in water by online intelligent detection based on fluorescence spectrum

In order to monitor the oil pollution of water real time and accurately for the environmental protection, an intelligent online detection system for the mineral oil in water is put forward in the present paper, based on the technology of ultraviolet fluorescence and internet of things (IOT). For this system, the resolution can be improved by using the higher precision asymmetric Czemy-Turner monochromator; the impact of light fluctuations on the results of exploration can be corrected by a bunch reference light; the optical system deviation caused by the instrument vibration can be reduced by optical fiber transmission; the coupling efficiency of fiber and output signal can be increased by a special fiber beam; the real-time measurement, data processing and remote control can be achieved by the control module and wireless communication module. This system has characteristics of high integration, high precision and good stability etc. The concentration of the unknown sample can be accurately calculated by the methods of parallel algorithms of chemometric metrology and the calculation errors caused by different components can be reduced by the theory of chemical correction factor analysis. The fluorescence spectra of three kinds of sample solution, diesel, engine and crude oil in preparative concentration of 10, 25, 50 and 100 mg x L(-1) were measured by this system respectively. The absorption wavelengths of the above-mentioned three oils were measured to be 256, 365 and 397 nm by a grating spectrometer; their absorbances were measured to be 0.028, 0.036 and 0.041 by fluorescence spectrophotometer, respectively. Their fluorescence emission wavelengths are 355, 419 and 457 nm respectively. Finally the concentration detection limits of the mineral oil in water of diesel, engine and crude oil were obtained, i.e., 0.03, 0.04 and 0.06 mg x L(-1) respectively. Their relative errors are 2.1%, 1.0% and 2.8% respectively.

Quantification of Blended Mineral Oil in Water Using Fourier Transform Near Infrared Transmission Spectroscopy

Quantification of Blended Mineral Oil in Water Using Fourier Transform Near Infrared Transmission Spectroscopy

Research on All Fiber-Optical Fluorescence System Measuring Mineral Oil in Water

A fluorescent optical fiber measuring system used to measure the concentration of the mineral oil in water is put forward in this paper according to the mechanism that the mineral oil in watercan emit fluorescence when excited by ultraviolet light. The pulse xenon lamp is used as excitation light source, while the linear CCD is adopted as the fluorescent signal of photoelectric detection components instead of the traditional photomultiplier tube in the system, combining with the optical fiber sensor technology and weak signal detection technology. It also equipped with the data acquisition card to realize data receiving and A/D conversion, using micro computer to store and display the data. This in turn realizes the accurate measurement of the concentration of mineral oil in water. The fluorescence optical fiber measuring system that used to measure the concentration of the mineral oil in water has the characteristics of simply structure, high sensitivity, wide linear range, probe passive and so on. The experimental result shows that this method is completely feasible.

Experimental Investigation of Viscous Fingering Instabilities in Emulsions Displacements

Experiments were conducted to analyze the viscous fingering instability that develops during the displacement of oil-in-water (O/W) emulsions. For this purpose, a horizontal rectilinear Hele-Shaw cell, which is an analogue for a homogeneous porous media, was used. Different emulsion solutions were prepared by dispersing different volume fractions of mineral oil in water using non-ionic surfactants. These emulsions were characterized systematically by examining their droplets size distribution and shear viscosity. Flow displacement experiments involved displacing the O/W emulsions by injecting water at different rates. The developments of the instability were characterized qualitatively by identifying the main mechanisms of finger development and growth. These results and the correlations between the properties of the fluids and the flow patterns were used to examine the flow dynamics and its effects on the viscous fingering instability. It was found that the development of the flow instability can be corr...

Evaluation of different storage methods for rapid and costeffective preservation of <i>Botryosphaeria</i> species

Four Botryosphaeria species isolated from grapevine namely Diplodia seriata (teleomorph B obtusa) Diplodia mutila (teleomorph B stevensii) Neofusicoccum parvum (syn B parva) and Neofusicoccum luteum (syn B lutea) were stored using 11 different methods Duplicate isolates were stored for 1 3 and 6 months as myceliumcolonised agar plugs and pycnidia in sterile water mineral oil 20 glycerol or potato dextrose agar (PDA) at room temperature (RT) 4C or 80C The viability of the four Botryosphaeria species was similar (81100) for all storage methods apart from pycnidia on pine needles at RT (68) but their overall growth rates differed between the storage methods (P

Interfacial shear rheology of interacting carbohydrate polyelectrolytes at the water–oil interface using an adapted conventional rheometer

A conventional rheometer was adapted for carrying out interfacial shear measurements. The interfacial shear viscosity and the interfacial creep compliance-time properties of mesquite gum or mesquite gum–chitosan mixed films were determined at the water–mineral oil interface. The ratio of chitosan to mesquite gum, and aging time, influenced the interfacial shear viscosity and interfacial creep compliance-time properties of the films. Electrostatic coulombic interactions arose between the negatively charged mesquite gum and the positively charged chitosan molecules, and the strength of the interaction was influenced by the relative charge density between both biopolymers. The interfacial shear viscosity and the interfacial viscoelastic properties of films obtained from 10% (w/w) mesquite gum aqueous solutions were boosted by the addition of chitosan at concentrations of 0.2–0.6% (w/w), but depressed by addition of chitosan at concentrations of 0.8–1.0% (w/w).

Application of Azoxystrobin for Control of Benomyl-Resistant Guignardia citricarpa on 'Valencia' Oranges in South Africa.

Azoxystrobin was evaluated in replicated small-plot trials from 1995 to 1999 for control of citrus black spot (CBS) on 'Valencia' oranges caused by Guignardia citricarpa. Applications of different rates of tank mixes of azoxystrobin and mancozeb during the susceptible period from October to January were compared with an untreated control as well as the standard four applications of mancozeb with or without mineral oil (1.20 g a.i./liter + 0.5% [vol/vol]/liter and 1.60 g a.i./liter of water, respectively). Two applications of azoxystrobin in tank mixtures with mancozeb and mineral oil (0.5% [vol/vol]/liter) in mid-November and mid-January at rates of 0.10, 0.15, and 0.20 g a.i./liter controlled CBS by more than 98 to 99%, 99 to 100% and 95 to 98%, respectively. Concomitantly, where mineral oil was not added to the fungicide mixture, azoxystrobin and mancozeb resulted only in 73 to 95%, 74 to 93% and 92.2 to 92.3% CBS control, respectively. Tank mixtures of benomyl, mancozeb, and mineral oil reduced CBS by only 29%, which could be attributed to the presence of benomyl-resistant pathogen isolates in the experimental orchard. Azoxystrobin applied at rates of 0.05, 0.075, and 0.10 g a.i./liter in tank mixtures with mancozeb (1.2 g a.i./liter) and mineral oil (0.5% [vol/vol]/liter of water) or Agral 90 (0.5% [vol/vol]/liter of water) were equally effective, reducing CBS by more than 99%. When mineral oil was compared to different adjuvants in tank mixtures with azoxystrobin and mancozeb, only mineral oil resulted in 100% clean exportable fruit. There was no difference between Sunspray 6E and Bac oil when mixed with azoxystrobin and mancozeb on the degree of disease control. Furthermore, the concentration of mineral oil in water can be lowered from 0.5% (vol/vol)/liter of water to 0.3% (vol/vol)/liter of water without a loss in efficacy against CBS. It is therefore, recommended that azoxystrobin (0.075 g a.i./liter) must be applied in tank mixtures with mancozeb (1.2 g a.i./liter) and mineral oil, which can be applied at either 0.5% (vol/vol)/liter of water or 0.3% (vol/vol)/liter of water.

Dynamic Interfacial Tension of Surfactant Mixtures at Liquid–Liquid Interfaces

Dynamic interfacial tensions for surfactant mixtures at liquid–liquid interfaces were obtained with a drop volume tensiometer. The surfactants tested were Triton X-100, palmitic acid, and Span 80 at both the water–hexadecane and water–mineral oil interfaces. Two-surfactant mixtures were examined with the surfactants initially dissolved in different phases to minimize bulk–phase interactions. For concentrations below the CMC, it was found that the adsorption kinetics of palmitic acid and Triton X-100 mixtures were dominated by the latter surfactant. Apparent diffusion coefficients were obtained for Triton X-100 both in the absence and in the presence of palmitic acid. These values were largely insensitive to the presence of palmitic acid. For mixtures of Span 80 and Triton X-100, the adsorption kinetics were found to be influenced significantly by both surfactants. In this case, relative changes in surfactant concentrations affected the dynamic interfacial tension of the mixed system. A previously proposed multicomponent adsorption model described the dynamic interfacial tension adequately at low concentrations of Triton X-100, when desorption could be neglected. At higher concentrations, modifications were needed to account for solubilization into the oil phase. These corrections allowed the model to describe the long time adsorption quite well. However, predicted values of short time interfacial tensions were overestimated, likely due to a synergistic interaction of the two surfactants.

Effect of Neck Formation on the Measurement of Dynamic Interfacial Tension in a Drop Volume Tensiometer

Dynamic interfacial tension values obtained by drop volume tensiometry will be affected under certain experimental conditions by the formation of a neck between the drop and the capillary tip. This phenomenon must be accounted for to obtain accurate values of interfacial tension. In this work, neck formation for a water–mineral oil system is studied under conditions where hydrodynamic effects can be neglected. A model originally developed for the determination of the surface tension of a suspended drop is modified for application to dynamic interfacial tensions of surfactant-containing liquids. The model relates apparent values of interfacial tension calculated from drops possessing necks to actual values. Experiments with Span 80 (sorbitan monooleate) and sodium dodecyl sulfate (SDS) surfactants in a mineral oil–water system are used to test the validity of the developed model. For the small tip diameter used, good agreement is obtained for Span 80 up to the critical micelle concentration, and for low concentrations of SDS, when the surfactant adsorption is diffusion-limited. In both cases, the neck diameter of the growing drop can be considered constant over the range of dynamic interfacial tensions tested.

Formulation Factors Affecting Release of Drug from Topical Formulations. 1. Effect of Emulsion Type upon in Vitro Delivery of Ethyl p‐Aminobenzoate

There are numerous kinetic and thermodynamic processes which occur during the transport of a topically applied drug from within its vehicle to the site of action in the skin. The present study compares the release and permeation of a model compound, ethylp‐aminobenzoate, from water, mineral oil, a mineral oil in water (O/W) emulsion, and a water in mineral oil (W/O) emulsion. These formulations are compared for differences in transport characteristics usingin vitrodiffusion studies and a synthetic polydimethylsiloxane membrane. Two factors appear prominent in influencing the release kinetics of the drug from its formulation. The first is the observation that the drug is released 2 times slower from mineral oil than from water at approximately equivalent thermodynamic activities, and the second is the appreciable lowering of the thermodynamic activity as a result of substantial micellar solubilization of the drug in the aqueous phase of the O/W emulsion. The thermodynamic activity effect predominants, resulting in a lower release rate from the O/W emulsion as compared to the W/O emulsion.

Microbial growth and accumulation in industrial metal-working fluids.

The dynamics of microbial growth in metal-working fluids (MWF) and the effect of the addition of biocides were studied in large fluid systems, in this case, one central tank which holds 150 m3. In this system, populations of Pseudomonas pseudoalcaligenes (greater than 10(8) CFU/ml) were sustained for a year, although large quantities of biocides were added. Quantitation of 3-OH lauric acid, a marker for many Pseudomonas spp., by gas chromatography indicated that the bacterial biomass exceeded the viable counts by approximately 15 times. Fungi were grown on several occasions, the dominating genera being Fusarium and Candida. Soon after the old MWF was removed and the tank was provided with fresh MWF, which consisted of an emulsion of mineral oil in water, there was a massive growth of P. pseudoalcaligenes that reached levels of greater than 10(8) bacteria per ml. Initially, only low concentrations of other species were found for some weeks. After this period, different enterobacteria and other gram-negative rods often appeared at high concentrations (10(7) and 10(8) bacteria per ml, respectively). Bacteria identified as P. pseudoalcaligenes showed great variation with respect to colony morphology and a certain heterogeneity with respect to biochemical characteristics. Certain bacterial species grew as microcolonies on metal strips immersed in the circulating MWF, but P. pseudoalcaligenes was not recovered from this habitat. The total bacterial count in the air surrounding the machines in the metal-working shop showed an inverse relation to increasing distance from the machine. The concentration of bacteria in the air varied because of the number of machines in use, temperature, and humidity.(ABSTRACT TRUNCATED AT 250 WORDS)

Gas-chromatographic determination of mineral oil in water

Abstract Contamination of water with mineral oil products may be detrimental for drinking water to be prepared from waters thus polluted. For determination of these pollutants a sensitive method was developed. Attention is paid mainly to a method of determination for oil components in true solution (aromatic hydrocarbons), which are considered most detrimental. The method described is based on extraction of the oil from the water and subsequent gas-chromatographic analysis of the resulting extracts. The method developed has been applied in the laboratory and in the field.