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Salts making crystals

Phosphonates are surface-active chelants and are widely used in industry for scale and corrosion control, and in cleaning agents, dispersants, and other applications. The annual sales of phosphonates in the U S A amount to over two billion dollars per year [8]. Phosphonates inhibit calcium scale formation by interfering with the crystal structure of calcium salts, making the crystals softer so that they are more easily removed by washing - the threshold effect [9]. A key application is controlling scale particularly in hard-to-reach places such as laundry and dishwashing machines. [Pg.284]

CRYSTALLIZATION—AS WATER IS REMOVED, THERE IS TOO LITTLE OF IT LEFT FOR THE SALT TO STAY IN SOLUTION. THE SALT MAKES ITS APPEARANCE AS TINY CRYSTALS. [Pg.21]

After a year he returned to Germany to teach and, as it turned out, to do the experiment that made him famous. The goal of the experiment was to prepare ammonium cyanate from a mixture of potassium cyanate and ammonium sulfate. He heated a solution of the two salts and crystallized the product. But the product didn t look like ammonium cyanate. It was a white crystalline material that looked exactly like urea Urea is a waste product of protein breakdown in the body and is excreted in the urine. Wohler recognized urea crystals because he had previously purified them from the urine of dogs and humans. Excited about his accidental discovery, he wrote to his teacher and friend Berzelius, "I can make urea without the necessity of a kidney, or even an animal, whether man or dog."... [Pg.294]

G. Rose says that Mitscherlich in Berlin in 1818 noticed that phosphates and arsenates gave very similar crystals, but was not able to make crystal measurements. Rose taught him this in exchange for instruction in chemical analysis. Mitscherlich throughout his life carried on many crystallographic investigations on salts which he prepared, which he never published. Three publications by Mitscherlich laid the foundations of the experimental and theoretical study of isomorphism ... [Pg.207]

From the final pond the concentrated brine (Table 1.3) with a density of about 1.25 g/cc was pumped nearly 4.8 km (3 mi 1.5 mi in 1967, Gadsby, 1967) to the processing plant in the town of Silver Peak. The plant had been converted from a silver ore cyanide-leach plant that had operated there from 1864-1961. In the conversion all of the tanks and settlers were rubber lined to reduce iron contamination in the product, and considerable new equipment was added. The solar pond brine was first reacted with lime to remove most of the residual magnesium and some of the sulfate and borate ions, and then a small amount of soda ash was added to precipitate most of the calcium from the lime reactions. The slurry from these operations was settled and filtered, and the overflow solution sent to storage tanks. From there the brine was pumped through filter presses to be totally clarified, and then heated to 93°C (200°F lithium carbonate has an inverse solubility) and reacted with dry soda ash and hot wash and make-up waters to precipitate the lithium carbonate product. Extra water was added to prevent salt from crystallizing, since the pond brine was samrated with salt. The lithium carbonate slurry was thickened in a bank of cyclones, and the underflow fed to a vacuum belt filter where it was washed and dewatered. The cyclone overflow and filtrate were... [Pg.107]

This intricate mode of crystallization requires more time to accomplish than, say, the entry of small ions into growing salt crystals. This, coupled with low chain mobility due to viscous effects, makes the rate of crystallization slow and accounts in part for the fact that with rapid cooling-called quenching-the temperature drops below T without crystallization. [Pg.206]

Black Liquor Soap Acidulation. Only two-thirds of a typical black Hquor soap consists of the sodium salts of fatty acids and resin acids (rosin). These acids are layered in a Hquid crystal fashion. In between these layers is black Hquor at the concentration of the soap skimmer, with various impurities, such as sodium carbonate, sodium sulfide, sodium sulfate, sodium hydroxide, sodium Hgnate, and calcium salts. This makes up the remaining one-third of the soap. Cmde tall oil is generated by acidifying the black Hquor soap with 30% sulfuric acid to a pH of 3. This is usually done in a vessel at 95°C with 20—30 minutes of vigorous agitation. Caution should be taken to scmb the hydrogen sulfide from the exhaust gas. [Pg.305]


See other pages where Salts making crystals is mentioned: [Pg.2900]    [Pg.407]    [Pg.236]    [Pg.533]    [Pg.61]    [Pg.62]    [Pg.522]    [Pg.667]    [Pg.852]    [Pg.3]    [Pg.418]    [Pg.257]    [Pg.191]    [Pg.522]    [Pg.667]    [Pg.852]    [Pg.270]    [Pg.97]    [Pg.456]    [Pg.2900]    [Pg.275]    [Pg.1107]    [Pg.510]    [Pg.371]    [Pg.172]    [Pg.119]    [Pg.268]    [Pg.533]    [Pg.487]    [Pg.526]    [Pg.95]    [Pg.522]    [Pg.528]    [Pg.459]    [Pg.328]    [Pg.31]    [Pg.151]    [Pg.1138]    [Pg.1655]    [Pg.43]    [Pg.375]    [Pg.133]   


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Crystallization salting

Salts, crystallization

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