Solvents dilution ratio

Effect of Solvent Dilution Ratio 19.5.1 Filtration Rate... 

Because tetrahydrofurfuryl alcohol is virtuaHy colorless, it is used in lacquer formulations for aH colors as weU as water-white clear products. More speciftcaHy, tetrahydrofurfuryl alcohol is a wetting dispersant for most pigments. It has a high boiling point, high toluene dilution ratio, and good miscibility with oils, eg, linseed and soya, and is an exceUent solvent for a wide range of resins. 

Table 4. Blush Resistance and Dilution Ratio of Common Industrial Solvents ...

Volume ratio (ASTM D1720) of diluent to solvent that just fails to dissolve completely 8 g of nitrocellulose in 100 mL of solvent. The higher the dilution ratio, the mote diluent the solution tolerates. 

Solvent Diluting liquid Average crystal size Limits of the crystal size M Ratio (length) (width)... 

For future theoretical developments in the field of transport properties of binary and higher-order mixtures, the simplest case seems to study the influence of the variation in mass of one of the species on the transport properties. Without a full understanding of this pure mass effect on the transport properties, it is not possible to analyze the effect of the translational-rotational coupling in real molecules. Toward this goal the simplest system that can be considered is a binary mixture at infinite solute dilution where the effect of the solute-solvent mass ratio on the solute diffusion can be studied. 

Although there has not been much theoretical work other than a quantitative study by Hynes et al [58], there are some computer simulation studies of the mass dependence of diffusion which provide valuable insight to this problem (see Refs. 96-105). Alder et al. [96, 97] have studied the mass dependence of a solute diffusion at an infinite solute dilution in binary isotopic hard-sphere mixtures. The mass effect and its influence on the concentration dependence of the self-diffusion coefficient in a binary isotopic Lennard-Jones mixture up to solute-solvent mass ratio 5 was studied by Ebbsjo et al. [98]. Later on, Bearman and Jolly [99, 100] studied the mass dependence of diffusion in binary mixtures by varying the solute-solvent mass ratio from 1 to 16, and recently Kerl and Willeke [101] have reported a study for binary and ternary isotopic mixtures. Also, by varying the size of the tagged molecule the mass dependence of diffusion for a binary Lennard-Jones mixture has been studied by Ould-Kaddour and Barrat by performing MD simulations [102]. There have also been some experimental studies of mass diffusion [106-109]. 

Titration of electro- Stoichiometric product yield lyte solution to other regardless of mixing ratio no electrolyte solution purification of starting materials required no waste of solvent Dilute solution (< 0.1%) requires excessive water filtration may be difficult 436... 

Where the element of interest is present in the sample as a soluble complex then it is often sufficient to dilute the sample with a suitable organic solvent. The sample may be diluted to the desired concentration level and any viscosity effects reduced. Not all solvents are suitable for flame AAS. Some, such as n-hexane and benzene, give smokey, unstable flames and should be avoided. Solvents such as white spirit, MIBK, n-heptane and xylene are acceptable. A dilution ratio should be chosen to bring the metal concentration into the region 0.2—0.8 absorbance units (or approximately fifty times the manufacturers quoted sensitivity). 

There are several dilute solution viscosity quantities used in the determination of the intrinsic viscosity. The size of macromolecules in solution is associated with an increase in viscosity of the solvent brought about by the presence of these molecules. Relative viscosity is a dimensionless quantity representing a solution/solvent viscosity ratio, r], = 7j/i o. where 17 and 170 are the solution and solvent viscosities, respectively. The specific viscosity yj p = 77 1 is the fractional increase in vis-... 

Poiseuille s law for laminar flow of liquids. The time required for a specihc volume of a liquid to flow through a capillary of dehned length and radius is proportional to the ratio of the viscosity by the density of the liquid itself. As the density of a dilute solution may be considered practically equal to that of the pure solvent, the ratio of efflux time of the solution, t, to that of solvent to, gives the relative viscosity ... 

Compilations of infinite-dilution activity coefficients, when available for the solute of interest, may be used to rank candidate solvents. Partition ratios at finite concentrations can be estimated from these data by extrapolation from infinite dilution using a suitable correlation equation such as NRTL [Eq. (15-25)]. Examples of these lands of calculations are given by Walas [Phase EquU ria in Chemical Engineering (Butterworth-Heinemann, 1985)]. Most activity coefficients available in the literature are for small organic molecules and are derived from vapor-liquid equilibrium measurements or azeotropic composition data. 

Properties Water-white liquid. D 0.8166 (20/20C), bp 150.6C, vap press 2.6 mm Hg (20C), flash p 102F (38.9C), autoign temp 99IF (532C), refr index 1.4110 (20C), bulk d 6.8 lb/gal (20C), nitrocellulose-toluene dilution ratio 3.9, fp -35C. Almost insoluble in water miscible with organic solvents. Combustible. 

Applications to Petroleum. In some cases, FAA has been used directly for analyzing petroleum samples (13,14,15,16), These analyses, in which the sample is diluted in a suitable combustible solvent and aspirated into the flame, are generally applied at concentrations above 1 ppm. Although the use of organic solvents increases FAA sensitivity for most metals, the technique was not well suited for the Project target level of 10 ng/g. This was because the dilution ratios required to eliminate matrix effects caused by such factors as viscosity and volatility were so large that FAA no longer had sufficient sensitivity. 

Solvent name Blush resistancea at 27°C, % rh T oluene Dilution ratio Aliphatic naphtha... 

For each of the three salts [72AUF/CAR], [72AUF/CAR2], the values for the five lowest concentrations were averaged to estimate a value at the third-lowest concentration with a solvent salt ratio of 8000 1. The difference between each experimental heat of solution measurement and the measurement (for the same hydrate) resulting in a solution with a solvent salt ratio of 8000 1 (0.00694 m) was calculated. Only values from the measurements with final solution concentrations below 0.056 m were used. Different values from 650 J mol to 200 J-mol were assumed for the heat of dilution to zero molality of the solution with a solvent salt ratio of 8000 1 (0.00694 m). Chukurov et al. [73CHU/DRA] provided an equation for heat of solution of the tetrahydrate in the concentration range 0.007 m to 0.03 m, and difference values based on that equation... 

If the enthalpy of dilution from a solution with a solvent salt ratio of 8000 1 to infinite dilution is assumed to be of the order of (520 + 100) J-mol all the experimental results enthalpy of solution are in reasonable agreement with each other. However, the values including those of Chukurov et al. [73CHU/DRA] at the lower concentrations) are compatible with the limiting-law slopes found for other 1 2 and 2 1 electrolytes [59LAN]. 

Figure A-21 Heats of dilution of hydrated nickel nitrate salts based on the experimental heats of solution and an assumed heat of dilution to infinite dilution of 520 J-mol for a solution with a solvent salt ratio of 8000 1. Heat of solution values for [73CHU/DRA] were based on the equation of the concentration dependence as reported in that paper (see text and Appendix A entry for [73CHU/DRA]).

Ml and V represent the molarity and volume of the stock solution, and M2 and V2 represent the molarity and volume of the dilute solution. Before dilution, a concentrated solution contains a fairly high ratio of solute particles to solvent particles. After adding more solvent, the ratio of solute particles to solvent particles has decreased. 

If a non-solvent is added dropwise to a cellulose nitrate solution, the cellulose nitrate eventually separates as a precipitate or gel. The volumetric ratio of non-solvent to solvent that is still tolerated in the solution is termed the dilution ratio. The dilution ratio is an empirical, dimensionless quantity that provides information on the solvency of a solvent or solvent mixture. In order to determine the dilution ratio toluene or butanol is used as diluent (non-solvent). 

Table 6 shows the dilution ratios for various diluents and solvents. As a rule the dilution ratio decreases with increasing boiling point of the solvent however, the solvent of lowest molecular mass in a homologous series (e.g., methanol, methyl acetate, methyl glycol) often behaves differently. 

Mixtures of two solvents frequently have a higher dilution ratio than the pure components ether-alcohol and toluene ethanol mixtures are better solvents for cellulose nitrate than any of the pure solvents ethyl acetate and butyl acetate are... 

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