A Method of Measuring the Concentration of Certain Polymers in Dilute Aqueous Solutions

1967 ◽  
Vol 71 (677) ◽  
pp. 381-383
Author(s):  
Y. Goren ◽  
P. O. Kane ◽  
J. F. Norbury
Keyword(s):  
Boundary Layer ◽  
Reynolds Number ◽  
Chemical Analysis ◽  
Aqueous Solutions ◽  
Polymer Solution ◽  
Analytical Method ◽  
Polymer Concentration ◽  
Low Concentrations ◽  
Dilute Aqueous Solutions ◽  
Flow Through

A technique has been devised for measuring the concentration of “Polyox” in dilute aqueous solutions. “Poly-ox”* is one of those polymers whose addition to water in low concentrations causes a reduction in skin friction (if the Reynolds number is sufficiently high) in turbulent flow through a pipe or boundary layer. (See, for example, ref. 1.) The analytical method is probably applicable to other polymers having this property, and it should be generally useful in this field of research. For example, in any experiment in which a polymer solution is injected at a point in a boundary layer, the method could be used to determine the distribution of polymer concentration at downstream sections. It is based on polarography, a well-established tool of chemical analysis of which an excellent account is given in ref. 2.

Effect of Polymer Additives on Cavitation Development and Noise in Water Flow Through an Orifice

1978 ◽  
Vol 100 (4) ◽  
pp. 493-499 ◽  
Author(s):  
R. O¯ba ◽  
Y. Ito¯ ◽  
K. Uranishi
Keyword(s):  
Aqueous Solutions ◽  
Polymer Concentration ◽  
Shock Pressure ◽  
Polymer Additives ◽  
Audio Frequency ◽  
Frequency Range ◽  
Dilute Aqueous Solutions ◽  
Flow Through ◽  
Cavitation Behavior ◽  
Audio Frequency Range

The cavitation behavior and the shock pressure were experimentally investigated in dilute aqueous solutions of polymer flowing through an orifice, and the following facts were observed: (i) Very small quantities of polymer additives effectively suppressed both the inception and the development of cavitation, (ii) nonspherical cavitation bubbles were observed at any polymer concentration tested here, and the nonsphericity tended to increase with concentration, (iii) the spectral frequencies of shock pressures were principally confined within the audio frequency range. With an increase in concentration, the energy of the pressures drastically decreased and the frequency range shifted downwards.

Cadmium removal from dilute aqueous solutions under galvanostatic mode in a flow-through cell

2015 ◽  
Vol 57 (48-49) ◽  
pp. 22809-22817 ◽  
Author(s):  
Ma. de Lourdes Llovera-Hernández ◽  
Alberto Álvarez-Gallegos ◽  
J.A. Hernández ◽  
Susana Silva-Martínez
Keyword(s):  
Aqueous Solutions ◽  
Cadmium Removal ◽  
Galvanostatic Mode ◽  
Dilute Aqueous Solutions ◽  
Flow Through

Adsorption of U(VI) from dilute aqueous solutions onto peat moss

2007 ◽  
Vol 95 (1) ◽  
Author(s):  
H. A. Omar ◽  
M. Aziz ◽  
K. Shakir
Keyword(s):  
Ionic Strength ◽  
Aqueous Solutions ◽  
Uranium Concentration ◽  
Probable Mechanism ◽  
Peat Moss ◽  
Optimum Conditions ◽  
Low Concentrations ◽  
Equilibrium Data ◽  
Dilute Aqueous Solutions

The adsorption of U(VI) onto peat moss has been studied as a function of uranium concentration, pH, shaking time and ionic strength. The pH and ionic strength of the solution markedly affect the extent of removal. The attainment of equilibrium is fast and the equilibrium data fit well the Freundlich, Langmuir and Dubinin-Radushkevich equations. A probable mechanism of uptake is discussed. Further studies demonstrate that under optimum conditions peat moss can be used for the treatment of waste solutions containing low concentrations of uranium.

Crosslinking of Guar and Guar Derivatives

SPE Journal ◽  
2007 ◽  
Vol 12 (03) ◽  
pp. 316-321 ◽  
Author(s):  
Cuiyue Lei ◽  
Peter E. Clark
Keyword(s):  
Polymer Solution ◽  
Critical Concentration ◽  
Polymer Concentration ◽  
Water Soluble ◽  
Solution Behavior ◽  
Water Soluble Polymer ◽  
Important Indicator ◽  
Low Concentrations ◽  
Wide Range ◽  
Overlap Concentration

Summary Crosslinking of guar and guar derivatives has played a major role in improving stimulation of oil and gas wells. While crosslinking has been used for a number of years, many facets of crosslinked systems are still not well understood. Part of the problem is that the traditional methods of determining the properties of crosslinked fluids work well for obtaining the data necessary for treatment design, but yield little insight into the nature of the crosslinked system. A good example of this is found in the development of low polymer concentration crosslinked gels. These gels are important because they lower costs and help to minimize formation damage. In this paper, methods for predicting crosslinkability at low concentrations are reported. The polymer literature is filled with methods for characterizing polymer solutions almost none of which find wide use in the development of crosslinked fracturing fluids. Dawson et al. (2000) first reported that the concentration at which a polymer solution transitions from dilute to semidilute could be used as a method for determining the potential for low concentration crosslinking in guar or guar-derivative solutions. To test this assertion, we have conducted a series of experiments that not only shows that the dilute-semidilute transition concentration is an important indicator for the polymers used in this study, but also presents a framework for exploring the potential of other polymer systems. These experiments show conclusively that low-polymer concentration crosslinking is strongly related to the value of the critical overlap concentration, c*. Both the critical overlap concentration and the critical crosslinking concentration increase in the order guar-3 < CMG < CMHPG < guar < HPG. In addition, we show that the critical crosslinking concentration for the range of polymer-crosslinking systems studied is correlated to the critical overlap concentration (). A strong case is presented for the ability to crosslink at low concentrations is a strong function of the polymer type and a weak function of the crosslinker type. Introduction Water-soluble polymers have been used for a number of years as thickening agents for stimulation fluids. Crosslinking was developed to improve the performance of these materials without increasing polymer concentration. Over the years, a number of different crosslinking agents have been used with success. There are several good discussions of polymer and crosslinking systems available (Economides and Nolte 1989; Gidley et al. 1989), and it is not the purpose of this paper to expand these discussions. Rather, we will approach the problem of crosslinking from the prospective of the molecular or solution properties that control or influence crosslinking. When a water-soluble polymer is hydrated, the viscosity of the resulting solution increases as a function of concentration. Starting at low concentrations and building to high concentrations, the viscosity appears to exhibit an exponential increase. This phenomenon has been studied for a wide range of polymer—solvent systems and seems to be universal. Early work divided the viscosity—concentration curve into two regions (Menjivar 1986; Robinson et al. 1982) that were separated at a critical concentration labeled c*. As the understanding of polymer solution behavior progressed and more sensitive instruments and experimental techniques were developed, the solution behavior was determined to be more complex (Rubinstein and Colby 2003).

An Increase in Base Pressure by Polymer Solutions Added to Separated Shear Layers

1980 ◽  
Vol 102 (3) ◽  
pp. 376-382 ◽  
Author(s):  
M. Kiya ◽  
M. Arie ◽  
S. Shoda
Keyword(s):  
Boundary Layer ◽  
Reynolds Number ◽  
Aqueous Solutions ◽  
Polymer Solutions ◽  
Shear Layers ◽  
Base Pressure ◽  
Pressure Increase

The change in the base pressure of a semicircular cylinder whose round side faced to the approaching stream was experimentally studied when the aqueous solutions of polyethyleneoxide (PEO) and polyacrylamide (PAM) were added to the boundary layer which eventually separated from the surface of the cylinder. The experiments were performed at a Reynolds number of 2.0 × 105, based on the base height of the cylinder. The base pressure was found to increase by 15 percent at its maximum by the injection of the polymer solutions as compared with the case of no injection. Saturation of the base-pressure increase was observed to exist with regard to the concentration of the polymer solutions and their velocity of injection.

scholarly journals Disproportionation and Polymerization of Plutonium(IV) in Dilute Aqueous Solutions

1983 ◽  
Vol 26 ◽  
Author(s):  
T. W. Newton ◽  
V. L. Rundberg
Keyword(s):  
Ionic Strength ◽  
Aqueous Solutions ◽  
Rate Constants ◽  
Second Order ◽  
Disproportionation Reaction ◽  
Reaction Products ◽  
Constant Ph ◽  
Low Concentrations ◽  
Dilute Aqueous Solutions ◽  
Ph Range

ABSTRACTThe rates of polymerization and disproportionation of Pu(IV) have been studied using low concentrations: (1.7 − 10) × 10−6M Pu, (0.8 − 12) × 10−4M HCI and 0.01M ionic strength. Osmium(II) complexes such as the tris−4,41−2,21−bipyridine complex were found to react rapidly with Pu(IV) but very slowly, if at all, with Pu(IV) polymer, Pu(lll), or Pu(V). Thus, it is possible to determine unreacted Pu(IV) in the presence of reaction products by using Os(II) complexes. Disproportionation reaction products, Pu(IlI) and Pu(V), were determined using their reactions with Ce(IV) sulfate. We find −d[Pu(IV)]/dt = k'[Pu(IV)]2 at constant pH. Log k1 varies from about 4.25 at pH 3 to about 7.0 at pH 4.1 (units for k1 are M−1min−1). The [H+] dependence varies from about −2 to −3 over the pH range studied. The measured rate is the sum of those for polymerization and disproportionation; the latter reaction amounts to about 75% of the total at pH 3 and 20% at pH 4. The second-order rate constants for disproportionation are very much larger than expected on the basis of extrapolation from 0.2 to 1.OM HClO, solutions. The products of the reaction do not affect the rate, but U(VI), aged Pu(IV) polymer, and CO2 increase the rate.

Steam distillation of taints from cream: IV. Vapour/liquid equilibrium relationships for mesityl oxide and some α-diketones as possible reference substances

1959 ◽  
Vol 26 (1) ◽  
pp. 24-32 ◽  
Author(s):  
F. H. McDowall
Keyword(s):  
Aqueous Solutions ◽  
Steam Distillation ◽  
Mesityl Oxide ◽  
Liquid Equilibrium ◽  
Low Concentrations ◽  
Dilute Aqueous Solutions ◽  
Equilibrium Relationships ◽  
The Relationship

1. Measurements, by means of a continuous vaporization equilibrium still, of vapour/liquid equilibrium relationships in the steam distillation of dilute aqueous solutions showed that for mesityl oxide the relationship was linear, equilibrium coefficient (CV/CL)= 74.2. For acetylpropionyl it was linear over the concentration range l–10 p.p.m. in the liquid, CV/CL=51, and above a concentration of 20 p.p.m. it was again approximately linear. At 20 and 50 p.p.m. in the liquid the values found for CV/CL were 34 and 21·5 respectively.3. For acetyl-iso-butyryl it was not linear even at very low concentrations, of the order of 1–3 p.p.m. in the liquid, but there was an approach to linearity at concentrations 0–1 p.p.m., CV/CL=240. At concentrations above 1 p.p.m. in the liquid there was a steady fall in the value for the equilibrium coefficient.4. For acetylvaleryl it was curvilinear even over the concentration range 0·1–4·0 p.p.m. in the liquid. At 0·5–1·0 p.p.m. in the liquid the equilibrium coefficient was of the order of 240. Above a concentration of 4 p.p.m. in the liquid the relationship was linear.5. For acetylcaproyl it was approximately linear only over the concentration 0·1–0·4 p.p.m. in the liquid, CV/CL=180. At 4 and 8 p.p.m. in the liquid the coefficients were 90 and 70 respectively.6. For acetylbenzoyl it was curvilinear at low concentrations, i.e. 0·1–0·5 p.p.m. in the liquid, CV/CL=30 decreasing to 16. Above this concentration there was a gradual fall in the equilibrium coefficient to 11·5 at 70 p.p.m. in the liquid.7. Of the substances investigated only diacetyl and acetylpropionyl and, within limits, acetylbenzoyl were considered to be of suitable properties for use as reference substances in detailed investigations on cream deodorization equipment.

The viscosity of dilute aqueous solutions of aliphatic alcohols

1982 ◽  
Vol 35 (3) ◽  
pp. 465 ◽  
Author(s):  
DM Alexander ◽  
DC Moy
Keyword(s):  
Aqueous Solutions ◽  
Aliphatic Alcohols ◽  
Low Concentrations ◽  
Dilute Aqueous Solutions ◽  
B Coefficients

Relative viscosities have been measured of dilute aqueous solutions of aliphatic alcohols, including methanol, ethanol, the propanols, the butanols and the pentanols, at temperatures of 278, 293 and 313 K at concentrations in the range 10-4-10-2 mol dm-3. The Jones and Dole B coefficients have been calculated and compared with literature data extrapolated to low concentrations.

An Experimental Investigation of the Flow in a Classical Venturimeter

1969 ◽  
Vol 184 (1) ◽  
pp. 133-160 ◽  
Author(s):  
D. Lindley
Keyword(s):  
Experimental Data ◽  
Boundary Layer ◽  
Reynolds Number ◽  
Separation Bubble ◽  
Area Ratio ◽  
Wall Region ◽  
Flow Mechanism ◽  
Number Range ◽  
Turbulent Transition ◽  
Flow Through

The flow through two classical 10 in diameter venturimeters of 0.5 area ratio is investigated to determine the nature of the flow mechanism within the meter and its variation with Reynolds number. Separation occurs at the throat entry, the size and position of the resulting bubble apparently remaining unchanged up to a throat Reynolds number of approximately 2.9 × 105, while beyond this point the separation bubble seems to disappear. An investigation of the wall region of the throat boundary layer shows it to be fully turbulent throughout the throat Reynolds number range tested from 4 × 104 to 7.5 × 105. A comparison of experimental data obtained from both air and water tests on the two meters indicates that the flow mechanism is substantially the same for both fluids. The experimental evidence suggests that any postulation of laminar-turbulent transition of the wall region of the boundary layer is inapplicable to the analysis of flow through classical venturimeters in a pipe having similar geometry to the meters studied.

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