Sugars contaminants

The following are some of the typical industrial applications for liquid-phase carbon adsorption. Generally liquid-phase carbon adsorbents are used to decolorize or purify liquids, solutions, and liquefiable materials such as waxes. Specific industrial applications include the decolorization of sugar syrups the removal of sulfurous, phenolic, and hydrocarbon contaminants from wastewater the purification of various aqueous solutions of acids, alkalies, amines, glycols, salts, gelatin, vinegar, fruit juices, pectin, glycerol, and alcoholic spirits dechlorination the removal of... 

In some process applications condensate becomes contaminated in sugar refining it may contain sugar, in paper manufacture and some other processes it may be contaminated with raw water, and where it feeds turbines or other machinery it is liable to contain oil or grease. In all these cases the condensate may still provide a better source of boiler feed than the available raw water, but it may need condensate filtration or softening plant before re-use. 

Frequently, column problems are caused by the samples that are being analyzed. This type of problem is more likely to occur on capillary columns because of their low capacity for contamination. Contamination results when the sample contains nonvolatile or even semivolatile materials such as salts, sugars, proteins, and so on. Column contamination is more frequently observed with splitless injection because larger amounts of material are being injected on the column. 

Process leaks of sugars, fats, colloidal materials, pectins, emulsions, and proteins cause stable foams in the boiler, leading to carryover and a further contamination cycle. 

In general, organic contaminants induce foaming and inorganics increase surface tension, although clearly there are exceptions. For example, sugar increases surface tension, while tannins, lignosulfonates, car-boxymethyl cellulose (CMC), phosphinocarboxylic acids (PCAs), and other dispersants reduce surface tension and help destabilize foams. 

Process leaks from food and beverage production or wood leachates often produce sugars, colloidal materials, pectins, emulsions, and proteins that cause stable foams in the boiler. These lead to carryover and further steam-condensate line contamination. The temporary use of a demulsifier or defoamer as part of the water treatment program may be of particular benefit, but again the condensate is unsuitable for return to the boiler. Other process leaks include ... 

NOTE Tannin chemistry has been used very successfully for many years in Africa and in Central and South America, in sugar refinery boilers operating at 650 psig and higher, without any measurable breakdown in performance or detectable contamination of steam from volatiles. 

Yields of osones obtained by the oxidation of sugars by Fenton s reagent are low, and the osones are invariably contaminated both with starting material and with the products of further oxidation in consequence, the method has had only limited application.44... 

The purification of a pneumococcal polysaccharide may be difficult, and the polysaccharide material is sometimes contaminated by a cell-wall component known as the C-substance. The methods for structural analysis of polysaccharides (which, like several of the pneumococcal polysaccharides, contain amino sugar and uronic acid... 

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