Water-insoluble solids

Dilute sodium hydroxide solution (and also sodium carbonate solution and sodium bicarbonate solution) can be employed for the removal of an organic acid from its solution in an organic solvent, or for the removal of acidic impurities present in a water-insoluble solid or liquid. The extraction is based upon the fact that the sodium salt of the acid is soluble in water or in dilute alkali, but is insoluble in the organic solvent. Similarly, a sparingly soluble phenol, e.g., p-naphthol, CioH,.OH, may be removed from its solution in an organic solvent by treatment with sodium hydroxide solution. 

This type of membrane consists of a water-insoluble solid or glassy electrolyte. One ionic sort in this electrolyte is bound in the membrane structure, while the other, usually but not always the determinand ion, is mobile in the membrane (see Section 2.6). The theory of these ion-selective electrodes will be explained using the glass electrode as an example this is the oldest and best known sensor in the whole field of ion-selective electrodes. 

AKDs are waxy, water-insoluble solids with melting points around 50 °C, and ASAs are viscous water-insoluble liquids at room temperature. It is necessary to prepare them as stabilised emulsions by dispersion in a cationic polymer (normally cationic starch). Small amounts of retention aid and surfactants may also be present. Particle size distributions are around 1 fim, and addition levels around 0.1% (of pure AKD or ASA) by weight of dry fibre. This is an order of magnitude lower than the amount of rosin used in rosin-alum sizing (1-2%). Emulsions of AKD are more hydrolytically stable than ASA, and the latter must be emulsified on-site and used within a few hours. 

The key to the successful application of high performance, pourable nitrocellulose plastisols lies in a reasonably priced, high quality source of fine-particle, at least partially colloided, spheroidal nitrocellulose. Here we are speaking of particles much finer than the well-known ball powder, produced by the Olin Mathieson Chemical Co. for small arms for over 30 years (7). Actually, particles on the order of 5-50/x diameter appear to be required to assure a reasonable continuum of uniformly plasticized nitrocellulose binder in a propellant containing 45% or more of combined crystalline oxidizer and powdered metal fuel. Such a continuum of binder is necessary to assure acceptable mechanical properties and reproducible burning characteristics of the finished propellant. Preincorporation of a certain content of the water-insoluble solids within the nitrocellulose microspheres is an effective means of helping to assure this continuum of binder and alleviates the requirements for extremely small ball size. The use of a total of 45% or more of crystalline oxidizer and (generally) metal fuel is essential if the propellant is to be competitive with other modern propellants now in service. 

Monoalkanolamine Condensates. Coco, lauric, oleic, and stearic monoethanolamides and monoisopropanolamides are the principal surfactants in the monoalkanolamide group (Table 24). Monoalkanolamides are generally water-insoluble solids that are easily solubilized by hydrophilic surfactants. Except for solubility and viscosity, properties and uses are similar to the diethanolamides. Manufacturing processes and yields have been described (96). 

Water-insoluble solids are potentized initially by trituration. This process breaks down drugs into nano particles which assume special importance because of their biological activity. Nano particles naturally occur in diseased tissues from which nosodes are prepared. The basis of liberation of dormant medicinal properties of drugs by trituration is the production of nano particles. Ethanol having a large non-polar part usually stabilizes specific water structures obtained during potentization of a drug. 

Suspension Polymerization Systems for Controlling Particle Size. Suspending Agents. Both types of suspension stabilizers—the finely divided water-insoluble solids and the soluble film formers—have been used extensively to prepare styrene polymers of a particle size between about 10 and 40 mesh. Examples of such materials are listed below ... 

NOTE CHB, container handling building WIL, water-immiscible liquid WIS, water-insoluble solid WML, water-miscible liquid and WSS, water-soluble solid. 

A mixture of 223 g. (1.26 moles) of -chloromethylnaphthalene [Org. Syntheses, 24, 30 (1944)] and a solution of 110 g. (1.7 moles) of potassium cyanide in 500 ml. of ethanol and 200 ml. of water is refluxed for 1 hour. The ethanol is distilled off, and the residue is washed with water and filtered to remove water-insoluble solid. After drying in vacuum, the material is distilled and the a-naphthylaceto-nitrile is collected at 175-185°/11-14 mm. 

Fluoride, chloride, bromide, and iodide derivatives of thallium(I) are well known. Their solubilities and photosensitivity are similar to the corresponding silver(I) systems. TIE is water-soluble, whereas the chlorides, bromides, and iodides are water-insoluble solids. This property is exploited in ligand-transfer chemistry involving thallium precursors. Some solid-state structures of thal-lium(I) salts of weakly coordinated anions show TT -halide interactions. Selective abstraction of a fluoride from a C-F bond, leading to thallium fluoride, has been described. The compound [ P(CH2CH2PPh2)3 RuH( 7 -ClTl)]PF6 represents the first metal complex containing an 77 -Cl-bonded TlCl ligand. This compound act as a thallium(I)-ion carrier. 

In some cases, the most convenient method for the purification of a solid consists in precipitating it from a solution in which it is contained as a derivative. A typical example is the purification of a water-insoluble solid carboxylic acid by dissolving it in sodium hydroxide solution, filtering, and precipitating the compound by the addition of acid. A similar procedure may be used with amines dissolve the compound in acid and precipitate it with a base. These procedures usuallv work quite well in that they utilize a chemical reaction to aid in separation from nonacidic or nonbasic impurities. 

The two water-insoluble solids, benzoic acid and o-chlorobenzoic acid, can be separated by treatment with an aqueous solution of sodium formate. What reaction takes place (Hint Look at the KaS in Table 18.2.)... 

Problem 22 1 Describe exactly how you would go about separating a mixture of the three water-insoluble liquids, aniline (b.p. 184 ), n-butylbenzene (b.p. 183 ), and /f-valeric acid (b.p. 187 ), recovering each compound pure and in essentially quantitative yield. Do the same for a mixture of the three water-insoluble solids, p-toluidine, o-bromobenzoic acid, and p-nitroanisole. 

The water-insoluble solids include hydrogenated soybean oil, hydrogenated vegetable oil, beeswax, and soy fatty acids and are usually used in a mixture of solvents to solubilize lipophilic drugs. 

Write the complete equation for the reaction between HN03( ) and water-insoluble solid MgC03. 

Enzymes are normally used as water-soluble homogeneous catalysts or immobilized onto water-insoluble solid supports. The many advantages of immobilized systems have been outlined in this chapter. Yet insoluble immobilized enzyme preparations can also have serious drawbacks. First, efficiency with macromolecular or insoluble... 

Not much is known about the normal azide Pd(N3)2 except that it is a brown, water-insoluble solid which is very sensitive to heat, friction, and impact [139,158]. It is precipitated when solutions of palladium salts and azide are combined, e.g., 0.1 M sodium azide and 0.01 M palladium perchlorate are mixed in molar ratios, but the precipitate cannot be dried without exploding [166]. This azide is occasionally obtained as an undesired intermediate to the complex paDadium azides. 

The simplest procedure is for a clear solution product, where no gums or water-insoluble solids are in the formulation. In this case, heat is usually not... 

Polymer coacervation can occur in either aqueous or organic liquids. Coacervation in aqueous liquids and the related processes are mainly used to encapsulate water-immiscible liquids or water-insoluble solid particles. On the other hand, coacervation in organic liquids, or sometimes called phase separation in organic liquids, is used to encapsulate core materials that are not miscible or soluble in the organic liquids. It may be induced by the addition of a nonsolvent to the polymer solution or by the addition of an incompatible polymer based on polymer-polymer incompatibility. This chapter will only discuss the coacervation in aqueous liquids. 

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