Ammonium hydrogen sulfate

Structural formula
General
Surname	Ammonium hydrogen sulfate
other names	Ammonium bisulfate
Molecular formula	NH 4 HSO 4
Brief description	white odorless solid
External identifiers / databases
CAS number 7803-63-6 EC number 232-265-5 ECHA InfoCard 100.029.332 PubChem 24655 Wikidata Q423524
properties
Molar mass	115.10 g mol −1
Physical state	firmly
density	1.79 g cm −3 (at 20 ° C)
Melting point	120 ° C (decomposition)
solubility	easily in water (115.1 g l −1 at 20 ° C)
safety instructions
GHS labeling of hazardous substances danger H and P phrases H: 314 P: 280-305 + 351 + 338-310
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Ammonium hydrogen sulfate is an ammonium salt of sulfuric acid . It has the formula NH ₄ HSO ₄ .

Extraction and presentation

Ammonium bisulfate formed during decomposition of ammonium sulfate at temperatures above 100 ° C, whereby ammonia is released. Ammonium hydrogen sulfate is produced in large quantities as a separation product in activated coke filter systems for industrial exhaust gases containing sulfur dioxide . The filters are charged with oxygen, ammonia and water vapor, whereby hydrogen sulphate and ammonium sulphate are formed via sulfuric acid:

${\displaystyle \mathrm {2\ SO_{2}\ +\ O_{2}+2\ H_{2}O\longrightarrow 2\ H_{2}SO_{4}} }$

${\displaystyle \mathrm {H_{2}SO_{4}\ +\ NH_{3}\longrightarrow (NH_{4})HSO_{4}} }$

${\displaystyle \mathrm {(NH_{4})HSO_{4}\ +\ NH_{3}\longrightarrow (NH_{4})_{2}SO_{4}} }$

properties

Ammonium hydrogen sulfate forms white, monoclinic, hygroscopic crystals. The substance decomposes at temperatures above 120 ° C, releasing sulfur oxides, nitrogen oxides and ammonia . A solution of 100 g of ammonium hydrogen sulfate in 1 l of water has a pH value of 1 at 20 ° C , i.e. it is in the strongly acidic range.

use

It is used for the production of ammonium peroxodisulphate , as an additive in nitrogen fertilizers, for fighting forest fires as a viscous solution / suspension in water and for the production of ammonium alum and flame retardants for cellulose products.

safety instructions

Ammonium hydrogen sulfate is classified as slightly hazardous to water ( WGK 1).

Individual evidence

1. ↑ ^{a b c d e f} Entry on ammonium hydrogen sulphate in the GESTIS substance database of the IFA , accessed on February 14, 2017(JavaScript required) .
2. ↑ ^{a b} data sheet ammonium hydrogen sulfate (PDF) from Carl Roth , accessed on December 14, 2010.
3. ↑ Heinz Brauer: Handbook of environmental protection and environmental protection technology: Volume 3: additive environmental protection: treatment of exhaust air and exhaust gases. Springer, 1996, ISBN 9783540580607 , p. 577.
4. ^ Jean D'Ans, Ellen Lax: Pocket book for chemists and physicists. 3. Elements, inorganic compounds and materials, minerals. 4th edition, Springer, 1997, ISBN 9783540600350 , p. 596.
5. ^ Arnold Willmes: Pocket book chemical substances: elements - inorganics - organics - natural substances - polymers. 3rd edition, Harri Deutsch Verlag, 2007, ISBN 9783817117871 , p. 115.
6. ↑ Patent.de: Process for the production of granulated ammonium sulfate. Patent DE4126806A1, February 11, 1993.