Sticky salts

Some waste feeds may contain a combination of abrasive particles and sticky salts. This can sometimes provide a benefit as tbe abrasive particles can scour the process surfaces and keep them sufficiently clear of solids buildup. U.S. Patent No. 5,620,606 teaches the addition of inert particles to SCWO feed to mitigate sohds build-up. 

Salt handling Not compatible sticky salts cause Compatible various approaches... 

With ASA, good first pass retention of ASA is paramount to good sizing efficiency, as any ASA not retained in the first pass can be easily hydrolysed in the white-water system. This is because the ASA dispersion is not as stable in the wet-end as that of rosin, or AKD, as these products are designed to be stable for a period of months. This hydrolysis product can react with calcium and/or magnesium to form sticky salts, which can deposit and cause many problems. If aluminium is not added to the ASA dispersion, then it should be added to the white-water system to react with any unretained, hydrolysed, ASA to prevent the formation of these salts, by formation of the less/non-sticky aluminium salt. There are appUcations of ASA that do not use aluminium species, where first pass ASA retention is optimised, but these tend to be in the minority. 

Sodium bicarbonate and sodium carbonate reach (at different levels) a good efficiency at T>355°F (180°C). They can be used in a wide range of temperatures but they involve some risk of sticky salt formation around 570-660°F (300-350°C)... 

The enamine protecting group was removed by dissolving 10 grams in aqueous acetone (250 ml water to 250 ml acetone) and vigorously stirring this solution at pH 2.5 for 1 hour. The acetone was removed in vacuo and the ester, which was salted out of the aqueous phase as a sticky yellow gum, was dissolved in ethyl acetate (200 ml) and washed twice with 200 ml portions of 1 N sodium bicarbonate and brine and dried over anhydrous magnesium sulfate. Careful addition of dry ester (about 50 ml) to the dry ethyl acetate layer... 

The chromiiun salts formed during the oxidation are quite sticky and tend to occlude product as well as starting material. 

The dimension of the resultant structure was visualized by atomic force microscopy (AFM). Indeed, the width of the fibers was reduced compared to that of SAF peptides however, its length was much more heterogeneous. Most fibers were also shown to be shorter than that of previously described coiled coil nanofibers. Fiber shortening could be related to the 1) weak association between sticky-ended coiled coils and 2) salt effects. It was found that sodium chloride and ammonium sulfate have a distinct effect on the fibril lateral aggregation, leading to short fibers in NaCl and long fibers in ammonium sulfate. 

It is a basic aluminium salt of sucrose octasulfate. It polymerizes at pH < 4 to form a sticky, viscid yellow white gel which adheres to ulcer base. The gel acts as a strong mechanical barrier because of a strong... 

Sucralfate is a basic aluminium salt of sucrose, a complex of sucrose octasulphate and aluminium hydroxide. At acid pH (<4), it forms a very sticky gel polymer, which adheres to epithelial cells and the base of ulcer craters. It has little or no antacid activity, but more importantly has a major cytoprotective action, both protecting the mucosa from damaging influences and also causing accelerated healing. It appears to work through a number of relatively poorly understood mechanisms, enhancing several gastric and duodenal protective mechanisms—different actions may be related to its chemistry as an aluminium salt, and to the sucrose octasulphate component. 

Although polymeric solvents have previously been prepared, they are usually based on pyridine, imidazole, or styrene and have the physical forms of a glass or a sticky rubber. Agents in the current application are liquids. Once dissolved poly(2-acrylamido-2-methyl-l-propanesulfonic acid) oxyethylene ammonium salts, however, can be directly converted into fabrics. 

Water is generated soon after the reaction mixture begins to reflux and is mostly removed by the toluene-water azeotropic distillation. The presence of a small amount of water appears to be essential to the reaction. However, too much water remaining in the reaction mixture mixes with the inorganic salts and forms a sticky, wet solid lump at the bottom of the flask that could be a potential problem for the stirring and subsequent filtration. 

This salt is much more difficult to obtain in dry, pure form than is the corresponding sulfate. It is very soluble in water, but from concentrated solution it is deposited in crystals which in color are almost identical with those of the sulfate. Upon exposure to air, even during filtration with the pump, the crystals turn yellow through oxidation. Probably this is not due to greater ease of oxidation on the part of the solid salt but to the physical conditions that prevail. The saturated, cold solution is very viscous and sticky, and absorbent paper absorbs this liquid very slowly. Owing to the great solubility of the salt, the solution has a low vapor pressure and does not tend to evaporate in the air. Consequently, the crystals remain coated with a film of concentrated mother liquor which oxidizes very fast in the air. 

When well-formed individual crystals have been obtained, filter them on a Witte plate, wash once with dilute nitric acid (1 3), pump as dry as possible, place the moist crystals in a suitable vessel, and put this in a desiccator over sulfuric acid. Watch the crystals carefully, with occasional stirring, and bottle them at once when they are dry. Do not touch them with the fingers, as this will discolor them. If they are allowed to overdry in the desiccator, they lose both crystal water and nitric acid and turn into a sticky mass of brownish-colored basic salt, which will not take up water from the air to reverse the reaction. Consequently, effloresced crystals cannot be used to complete the drying of the moist crystals. If the crystals are exposed to moist air, they deliquesce, undergo hydrolysis in the resulting solution, and form a basic salt. If they are bottled before they are dry, they will in time become discolored. If properly prepared, they will remain perfectly transparent and have a very pretty amethyst color, the intensity of which depends upon the size of the crystals. Crystals of iron alum have the same color. 

The alcohol may be made practically anhydrous by refluxing with successive portions of fused potassium carbonate until no further action is observed. The carbonate will remain finely divided and will not become sticky when water is absent. A considerable amount of allyl alcohol is lost mechanically during the drying in this way, so that the potassium carbonate which is used here should be employed for the salting out of fresh portions of allyl alcohol in the first part of subsequent preparations. The allyl alcohol thus produced is dry enough for all practical purposes (98-99 per cent) and it is unnecessary to dry with lime or barium oxide as advised in the literature in order to remove all of the water. The allyl alcohol obtained by this process boils at 94-97°-... 

Indeed, the Na-HMPA route consistently provided the cleanest products and has been the only synthesis to provide solutions of Na3[M(CO)4]. It is often important to use solutions rather than slurries of trianion salts to minimize the formation of side products during the reactions of these materials with electrophiles. Until recently, product separation from the viscous and high-boiling HMPA has always been a problem (and remains so in some cases). For example, addition of excess THF to solutions of Na3[M(CO)4] in HMPA invariably resulted in the formation of sticky solids that contained HMPA and did not analyze satisfactorily (14). But recently, it was discovered that addition of these HMPA solutions to excess liquid ammonia resulted in practically quantitative precipitation of tan to pale yellow brown solids, which provided satisfactory elemental analyses of unsolvated Na3[M(CO)4] (M = Mn, Re). Virtually all impurities remained in the HMPA-NHj filtrate [Eqs. (4) and (5)]. 

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