Fluorosilicate, ammonium

Applications. Ammonium bifluoride solubilizes sihca and sihcates by forming ammonium fluorosilicate [16919-19-0] (NH 2 ip6 ... 

Ammonium acetate Ammonium adipate Ammonium benzoate Ammonium bicarbonate Ammonium biflluoride Ammonium binoxalate Ammonium bisulfate Ammonium bitartrate Ammonium tetraborate Ammonium bromide Ammonium carbonate Ammonium chloride Ammonium citrate Ammonium diclnomate Ammonium fluoride Ammonium fluorosilicate Ammonium gluconate Ammonium iodide Ammonium molybdate Ammonium nitrate Ammonium oxalate Ammonium perchlorate Ammonium picrate Ammonium polysulfide Ammonium salicylate Ammonium stearate Ammonium sulfate Ammonium sulfide (hydrosulfide) Ammonium tartrate Ammonium tliiocyanate Ammonium thiosulfate... 

Reactions with salts. This procedure is more limited and is illustrated by the use of chromium chloride solutions under reflux for partial dealumination of Y and X zeolites (19), as well as of erionite (20). It is assumed that in this case a partial substitution of chromium for aluminum takes place, leading to the formation of Si-O-Cr bonds in the framework (19). Up to 40 percent of aluminum was removed by this method. Zeolites can also be dealuminated with solutions of ammonium fluorosilicate (107). 

The 1980s saw major developments in secondary synthesis and modification chemistry of zeolites. SUicon-enriched frameworks of over a dozen zeolites were described using methods of (i) thermochemical modification (prolonged steaming) with or without subsequent acid extraction, (ii) mild aqueous ammonium fluorosilicate chemistry, (iii) high-temperature treatment with silicon tetrachloride and (iv) low-temperature treatment with fluorine gas. Similarly, framework metal substitution using mild aqueous ammonium fluorometaUate chemistry was reported to incorporate iron, titanium, chromium and tin into zeolite frameworks by secondary synthesis techniques. 

Ammonium fluorosilicate [16919-19-0] M 178.1. Crystd from water (2inl/g). 

FLUORURE de SULFURYLE (French) (2699-79-8) see sulfliryl fluoride. FLUORURO AMONICO (Spanish) (12125-01-8) see ammonixun fluoride. FLUORURO de ZINC (Spanish) (7783-49-5 73640-07-0) see zinc fluoride. FLUOSILICATE de AMMONIUM (French) or FLUOSILICATO AMONICO (Spanish) (1309-32-6) see ammonium fluorosilicate. 

AMMONIUM FLUOROSILICATE (1309-32-6) Aqueous solution is acidic. Contact with acid or acid fumes forms toxic fluorine. Keep away from strong oxidizers. 

Ammonium fluorosilicate Ammonium formate Ammonium hydride, cone. (1050LF) Ammonium iodide Ammonium lactate... 

Ammonium fluorosilicate (INCI) Ammonium fluosilicate. See Ammonium silicofluoride Ammonium formate... 

Fine alumina dust is also insecticidal. When larvae crawl over wet dust there is no effect because moisture is present. However, the skin has lost its oily protection by adsorption on the alumina and the insect dries out and dies quickly when placed in dry air (165). A combination of aerogel and ammonium fluorosilicate was especially effective for controlling mites on caged reptiles (166). Silica gel insecticides killed DDT-resistant mosquitoes (167) boric acid-modified silica aerogel was effective against cockroaches, and it was lethal even when their mouths were waxed shut so they could not eat it (168, 169). 

In practice the only chemically produced HSY-zeolite to be used on a large scale was made by reaction of NH4Y-zeohte with ammonium fluorosilicate... 

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