Solubility organic substances

Reactions involving organic substances have some special features. Many of these substances are poorly soluble in aqueous solutions. Sometimes their solubilities can be raised by adding to the solution the salts of aromatic sulfonic acids with cations of the type [NHJ or alkali metal ions. These salts have a salting-in effect on poorly soluble organic substances. In many cases solutions in mixed or nonaque-ous solvents (e.g., methanol) are used. Suspensions of the organic substances in aqueous solutions are also useful for electrosynthesis. 

Dyes, often also called coloring matters or colorants, are intensely colored, soluble organic substances used to impart color to fibrous materials (see Textbox 66). Not all colored and soluble organic substances, however, are dyes only those whose molecules have a considerable structural complexity are useful for imparting color to other materials. Moreover, a substance is considered a dye only if the color it imparts is fairly permanent, that is, resistant to fading and disappearance. 

Billington, J.W., Huang, G.L., Szeto, F., Shiu, W.Y., Mackay, D. (1988) Preparation of sparingly soluble organic substances I. Single component systems. Environ. Toxicol. Chem. 7, 117-124. 

Use of the compound to synthesize soluble dyes ceased as of 1986, when better dyes from other sources were introduced. The distinction between dyes and pigments is not always clear. Pigments are almost without exception insoluble and exist as finely divided solid powders that are insoluble but wettable under the eonditions of use. Dyes are almost always soluble organic substances used in coloring textiles or other fibrous substances. 

From this result and those of the determinations of sections 1-4, the percentage of combined tannin is obtained by subtracting from 100, the sum of the percentages of moisture (taken as 18 if the other components are referred to the substance with normal moisture content), ash, fat, soluble organic substances and hide substance determined as above. 

Blaschke, H. 1979. Leaching of water-soluble organic substances from coniferous needle litter. Soil Biology and Biochemistry 11 581—584. 

Not only analytical or preparative separations can be performed on cyclodextrin polymer columns, but also undesired components can be removed from aqueous solutions, bitter tasting substances (narin-gin, limonin) can be removed or at least their concentration can be strongly reduced after treatment of citrus juice with cyclodextrin polymers in batch or column process (65,66). Phenylalanine can be eliminated from dietetic protein hydrolysates (67), water-soluble organic substances (e.g. polychlorinated biphenyls (68), 2-naph-talenecarboxylate or phenol can be removed from aqueous solutions (e.g. from pharmaceutical wastewater) by polystyrene-cyclodextrin derivatives (69), by 8-cyclodextrin immobilized on cellulose (70) or by 6-cyclodextrin-polyurethane polymer (71). 

Amberlite XAD-2 polymeric adsorbent beads for adsorbing water-soluble organic substances Marketed by Rohm and Haas Company, Philadelji a, PA... 

Effect of Mineral Salts. As cellular water is frozen, mineral salts and soluble-organic substances become concentrated in the remaining unfrozen phase. This increase in solute concentration, with corresponding changes in ionic strength and pH, is believed to affect dissociation and/or denaturation of proteins (1,2,62,96-98). Experiments by Fukumi et al. (99) support this theory. They found that freeze denaturation of washed actomyosin from Alaska pollack muscle was accelerated by the presence of Ca2+, Mg2+, K+, and Na+ ions and reduced by their removal. 

Aoyama M. (1996a), Fractionation of water-soluble organic substances formed during plant residue decomposition and high performance size exclusion chromatography of the firactions. Soil Sci. Plant Nutr., 42, 1, 31-40. 

Bilhngton, J.W., G.-L. Huang, F. Szeto, W.Y. Shiu, and D. Mackay. Preparation of Aqueous Solutions of Sparingly Soluble Organic Substances I. Single Component Systems, Environ. Toxicol. Chem., 7 117-124 (1988). 

Hori M, Ohta S, Murao N, Yamagata S (2003) Activation capability of water soluble organic substances as CCN. J Aerosol Sci 34 419-448... 

---