Lithiumhydrid

Bezeichnung:Lithiumhydrid

CAS-Nr7580-67-8

Englisch Name:Lithium hydride

CBNumberCB7319774

SummenformelHLi

Molgewicht7.95

MOL-Datei7580-67-8.mol

Synonyma

Lithiumhydrid

Lithiumwasserstoff

Lithiumhydrid physikalisch-chemischer Eigenschaften

Schmelzpunkt	680 °C(lit.)
Dichte	0.82 g/mL at 25 °C(lit.)
storage temp.	Store below +30°C.
Löslichkeit	Slightly soluble in dimethylformamide. Insoluble in acetone, benzene and toluene.
Aggregatzustand	powder
Farbe	White to gray
PH	>7 (21g/l, H2O, 20℃)
Geruch (Odor)	odorless
Wasserlöslichkeit	reacts
Sensitive	Air & Moisture Sensitive
Merck	14,5533
Expositionsgrenzwerte	TLV-TWA 0.025 mg/m³ (ACGIH).
InChI	InChI=1S/Li.H
InChIKey	SIAPCJWMELPYOE-UHFFFAOYSA-N
SMILES	[LiH]
CAS Datenbank	7580-67-8(CAS DataBase Reference)
NIST chemische Informationen	Lithium hydride(7580-67-8)
EPA chemische Informationen	Lithium hydride (7580-67-8)

Sicherheit

Kennzeichnung gefährlicher	F,C,T
R-Sätze:	14-34-25-14/15
S-Sätze:	16-26-27-36/37/39-7/8-45-25
RIDADR	UN 1414 4.3/PG 1
OEB	D
OEL	TWA: 0.025 mg/m3
WGK Germany	2
RTECS-Nr.	OJ6300000
F	10
TSCA	Yes
HazardClass	4.3
PackingGroup	I
HS Code	28500090
Giftige Stoffe Daten	7580-67-8(Hazardous Substances Data)
Toxizität	LD50 orally in Rabbit: 78 mg/kg
IDLA	0.5 mg/m3

Gefahreninformationscode (GHS)

Lithium hydride Chemische Eigenschaften,Einsatz,Produktion Methoden

ERSCHEINUNGSBILD
GERUCHLOSER WEISSER BIS GRAUER HYGROSKOPISCHER FESTSTOFF IN VERSCHIEDENEN FORMEN. VERFäRBT SICH DUNKEL BEI KONTAKT MIT LICHT.
PHYSIKALISCHE GEFAHREN
Staubexplosion der pulverisierten oder granulierten Substanz in Gemischen mit Luft möglich.
CHEMISCHE GEFAHREN
Kann sich beim Kontakt mit Luft spontan entzünden. Reagiert sehr heftig mit Oxidationsmitteln, Säurenund Wasser unter Bildung brennbarer/explosionsfähiger Gase (z.B. Wasserstoff, ICSC-Nr. 0001) und, im Fall von Wasser, Lithiumhydroxid, welches stark alkalisch reagiert. Bei Kontakt mit heißen Gegenständen oder Flammen Zersetzung unter Bildung reizender alkalischer Rauche.
ARBEITSPLATZGRENZWERTE
TLV: 0,025 mg/m?(als TWA) (ACGIH 2005).
MAK: IIb (nicht festgelegt, aber Informationen vorhanden) (DFG 2008).
AUFNAHMEWEGE
Aufnahme in den Körper durch Inhalation des Aerosols und durch Verschlucken.
INHALATIONSGEFAHREN
Verdampfung bei 20°C vernachlässigbar; eine gesundheitsschädliche Partikelkonzentration in der Luft kann jedoch schnell erreicht werden.
WIRKUNGEN BEI KURZZEITEXPOSITION
WIRKUNGEN BEI KURZZEITEXPOSITION:
Die Substanz verätzt Augen, Haut und Atemwege. Inhalation des Aerosols kann zu Lungenödem führen (s. Anm.).
LECKAGE
NICHT in die Kanalisation spülen. Verschüttetes Material in Behältern sammeln. Reste sorgfältig sammeln. An sicheren Ort bringen. Chemikalienschutzanzug mit umgebungsluftunabhängigem Atemschutzgerät.
R-Sätze Betriebsanweisung:
R14:Reagiert heftig mit Wasser.
R34:Verursacht Verätzungen.
R25:Giftig beim Verschlucken.
R14/15:Reagiert heftig mit Wasser unter Bildung hochentzündlicher Gase.
S-Sätze Betriebsanweisung:
S16:Von Zündquellen fernhalten - Nicht rauchen.
S26:Bei Berührung mit den Augen sofort gründlich mit Wasser abspülen und Arzt konsultieren.
S27:Beschmutzte, getränkte Kleidung sofort ausziehen.
S36/37/39:Bei der Arbeit geeignete Schutzkleidung,Schutzhandschuhe und Schutzbrille/Gesichtsschutz tragen.
S7/8:Behälter trocken und dicht geschlossen halten.
S45:Bei Unfall oder Unwohlsein sofort Arzt zuziehen (wenn möglich, dieses Etikett vorzeigen).
S25:Berührung mit den Augen vermeiden.
Beschreibung
Lithium hydride is an off-white to grayish,translucent, odorless solid or white powder that darkens rapidly on exposure to light. Molecular weight = 7.95; Specificgravity (H2O:1)=0.78; Boiling point = 850℃ (decomposesbelow BP); Freezing/Melting point = 689℃; Autoignitiontemperature = 200℃. Hazard Identification (based onNFPA-704 M Rating System): Health 3, Flammability 4,Reactivity 2. A combustible solid that can form airbornedust clouds which may explode on contact with flame, heat,or oxidizers.
Chemische Eigenschaften
Lithium hydride (LiH) is a crystalline salt substance(face-centered cubic) that is white in its pure form, As an engineering material, it has properties of interest in many technologies. For example,the high hydrogen content and light weight of LiH make it useful for neutron shields and moderators in nuclear power plants. In addition, the high heat of fusion combined with light weight make LiH appropriate for heat storage media for solar power plants on satellites and may be used as a heat sink for different applications. Typically, processes for production of LiH involve handling of LiH at temperatures above its meltingpoint (688 DC). Type 304L stainless steel is utilized for many process components handling molten LiH.

Lithium hydride is a typical ionic hydride with lithium cations and hydride anions. Electrolysis of molten material results in formation of lithium metal at the cathode and hydrogen at the anode. The lithium hydride-water reaction, which results in the release of hydrogen gas, is also indicative of a negatively charged hydrogen.
Chemische Eigenschaften
Lithium hydride is an off-white to grayish, translucent, odorless solid or white powder that darkens rapidly on exposure to light. Pure lithium hydride forms colorless, cubic crystals. The commercial product contains traces of impurities, e.g., unreacted lithium metal, and is consequently light gray or blue. Lithium hydride is thermally very stable, being the only ionic hydride that melts without decomposition at atmospheric pressure (mp 688 ℃). In contrast to the other alkali metal hydrides, lithium hydride is slightly soluble in inert polar organic solvents such as ethers. It forms eutectic mixtures with a large number of salts. Lithium hydride is stable in dry air but ignites at increased temperature. In moist air it is hydrolyzed exothermically; finely divided material can ignite spontaneously. At elevated temperature, it reacts with oxygen to form lithium oxide, with nitrogen to form lithium nitride and hydrogen, and with carbon dioxide to form lithium formate.
Physikalische Eigenschaften
White crystalline solid; cubic crystals; density 0.82 g/cm³; melts at 686.4°C; decomposes in water; soluble in acids.
Verwenden
Lithium hydride is used in the manufactureof lithium aluminum hydride and silane, as apowerful reducing agent, as a condensationagent in organic synthesis, as a portablesource of hydrogen, and as a lightweight nuclear shielding material. It is now beingused for storing thermal energy for spacepower systems (Morris et al. 1988).
Verwenden
Lithium hydride is a bluish-white crystal that is flammable in moisture. Used as a source of hydrogen gas that is liberated when LiH becomes wet. LiH is an excellent desiccant and reducing agent as well as a shield that protects from radiation created by nuclear reactions.
Verwenden

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Industry

Application

Role/benefit

Hydrogen

Hydrogen storage

Storage material/has the highest hydrogen content of any hydride

Hydrogen preparation

Hydrogen source/reacts violently with water to yield hydrogen

Nuclear

Nuclear reactors

Neutron shield material

Thermonuclear weapons

Fusion fuel (lithium-6 deuteride)

Astronomy

Rocket fuel

Excellent thermal value

Organic chemistry

Synthesis of complex metal hydrides

Raw material

Preparation of LiAlH₄,LiBH₄ and LiBHET₃,etc.

Preparation of other hydrides amides and 2H isotopic compound

Reducing agent
synthetische
Lithium hydride is prepared by heating lithium metal with hydrogen above 440°C. The reaction is exothermic and can be controlled once it is initiated, without external heating. The heat of formation is greater than that of sodium hydride: 2Li + H2 → 2LiH
Definition
lithium hydride: A white solid,LiH; cubic; r.d. 0.82; m.p. 680°C; decomposesat about 850°C. It is producedby direct combination of theelements at temperatures above500°C. The bonding in lithium hydrideis believed to be largely ionic;i.e. Li⁺H^- as supported by the factthat hydrogen is released from theanode on electrolysis of the moltensalt. The compound reacts violentlyand exothermically with water toyield hydrogen and lithium hydroxide.It is used as a reducing agent toprepare other hydrides and the 2Hisotopic compound, lithiumdeuteride, is particularly valuable fordeuterating a range of organic compounds.Lithium hydride has alsobeen used as a shielding material forthermal neutrons.
Reaktionen
Lithium hydride reacts vigorously with water, forming lithium hydroxide with the evolution of hydrogen:
LiH + H2O → LiOH + H2
The hydride also reacts with ammonia forming lithium amide and evolving hydrogen:
LiH + NH3 → LiNH2 + H2
Lithium hydride is a strong reducing agent and would, therefore, react with compounds that contain oxygen. Even many highly stable oxides of metals and nonmetals can be reduced. It reduces metal oxides to metals and carbon dioxide to carbon:
Fe3O4 + 4LiH → 3Fe + 4NaOH
2LiH + CO2 → Li2O + C + H2O
It undergoes violent reactions with oxidizing agents.
Lithium hydride reacts with aluminum hydride forming lithium aluminum hydride, a powerful reducing agent: LiH + AlH3 → LiAlH4
Lithium hydride consisting of Li+ and H– ions exhibits properties of an ionic salt, both cationic and anionic; such as a strong electrolyte. Thus, when electrolyzed at temperatures slightly below its melting point, it dissociates to Li+ and H¯ ions. Hydrogen gas is liberated at the anode.
The hydride ion, H:¯ being a strong base, would react with alcohols, forming alkoxides and liberating hydrogen:
CH3CH2OH + LiH → CH3CH2OLi + H2
(ethanol) (lithium ethoxide)
(CH3)3COH + LiH → (CH3)3COLi + H2
(tert-butanol) (lithium tert-butoxide)
Allgemeine Beschreibung
A white or translucent crystalline mass or powder. The commercial product is light bluish-gray lumps due to the presence of minute amounts of colloidally dispersed lithium.
Air & Water Reaktionen
Burns readily in air, particularly if powdered. May ignite spontaneously in moist air. Reacts rapidly with water to form caustic lithium hydroxide and hydrogen [Bretherick 1979 p. 107].
Reaktivität anzeigen
Lithium hydride is a strong reducing agent. May decompose violently in contact with most oxidizing materials. Reacts exothermically with water to form caustic lithium hydroxide and hydrogen gas; the hydrogen may ignite. May ignite spontaneously in moist air. Mixtures with liquid oxygen are explosive. Ignites on contact with dinitrogen oxide [Mellor, 1967, vol. 8, suppl. 2.2, p. 214].
Health Hazard
The health hazard due to lithium hydride maybe attributed to the following properties: (1)corrosivity of the hydride, (2) its hydrolysisto strongly basic lithium hydroxide, and (3)toxicity of the lithium metal. However, thelatter property, which may arise becauseof the formation of lithium resulting fromthe decomposition of lithium hydride andthe metabolic role of lithium, is not yetestablished.
This compound is highly corrosive to skin.Contact with eyes can produce severe irritationand possible injury. It can hydrolyzewith body fluid, forming lithium hydroxide,which is also corrosive to the skin andharmful to the eyes. Animal tests indicatedthat exposure to its dust or vapor at a levelexceeding 10 mg/m³ eroded the body fur andskin, caused severe inflammation of the eyes,and led to the destruction of external nasalseptum (ACGIH 1986). No chronic effectswere observed.
Brandgefahr
In a fire, irritating alkali fumes may form. Lithium hydride can form airborne dust clouds which may explode on contact with flame, heat, or oxidizing materials. Additionally, spontaneous ignition occurs when nitrous oxide and Lithium hydride are mixed. Lithium hydride also forms explosive mixtures with liquid oxygen. Contact with heat, moisture or acid causes exothermic reaction and evolution of hydrogen as well as lithium hydroxide. Incompatible with air and moisture, nitrous oxide, strong oxidizers, and liquid oxygen. Lithium hydride may ignite spontaneously in air and should be maintained and handled out of contact with air and moisture. Any contact with nitrous oxide; airborne powders may ignite upon reaching moisture.
Sicherheitsprofil
Poison by inhalation. A severe eye, skin, and mucous membrane irritant. Upon contact with moisture, lithium hydroxide is formed. The LiOH formed is very caustic and therefore highly toxic, particularly to lungs and respiratory tract, skin, and mucous membranes. The powder ignttes spontaneously in air. The solid can ignite spontaneously in moist air. Mixtures of the powder with liquid oxygen are explosive. Ignttes on contact with dinitrogen oxide, oxygen + moisture. To fight fire, use special mixtures of dry chemical. See also LITHIUM COMPOUNDS and HYDRIDES.
mögliche Exposition
Lithium hydride is used in preparation of lithium aluminum hydride; as a desiccant; it is used in hydrogen generators and in organic synthesis as a reducing agent and condensing agent with ketones and acid esters; it is reportedly used in thermonuclear weapons.
Erste Hilfe
If this chemical gets into the eyes, remove anycontact lenses at once and irrigate immediately for at least15 min, occasionally lifting upper and lower lids. Seek medical attention immediately. If this chemical contacts theskin, remove contaminated clothing and wash immediatelywith soap and water. Seek medical attention immediately. Ifthis chemical has been inhaled, remove from exposure,begin rescue breathing (using universal precautions, including resuscitation mask) if breathing has stopped and CPR ifheart action has stopped. Transfer promptly to a medicalfacility. When this chemical has been swallowed, get medical attention. If victim is conscious, administer water ormilk. Do not induce vomiting. Medical observation isrecommended for 24-48 h after breathing overexposure, aspulmonary edema may be delayed. As first aid for pulmonary edema, a doctor or authorized paramedic may consideradministering a corticosteroid spray.
Lager
The product should be handled under an inert atmosphere to avoid contamination and a fire. Powdered lithium hydride burns readily when exposed to the air. However, large pieces of the material are less flammable. Lithium hydride, like other strong bases, is harmful to the skin and should be handled with caution.
Versand/Shipping
UN1414 Lithium, Hazard Class: 4.3; Labels: 4.3-Dangerous when wet material. UN2805 Lithium hydride, fused solid, Hazard Class: 4.3; Labels: 4.3- Dangerous when wet material
läuterung methode
It should be a white powder; otherwise replace it. It darkens rapidly on exposure to air and is decomposed by H2O to give H2 and LiOH, and reacts with lower alcohols. One gram in H2O liberates 2.8L of H2 (could be explosive). [D.nges in Handbook of Preparative Inorganic Chemistry (Ed. Brauer) Academic Press Vol I p 987 1963.]
Inkompatibilitäten
A Strong reducing agent. Incompatible with oxidizers, halogenated hydrocarbons; acids can cause fire and explosion. Reacts with water, forming caustic lithium hydroxide and flammable hydrogen gas; reaction may cause ignition. May ignite spontaneously in moist air and may reignite after fire is extinguished. Dangerous when wet. Reacts with water to form hydrogen and lithium hydroxide. Powdered form and liquid oxygen form an explosive compound. Decomposes exothermically on contact with acids and upon heating to about 500C, producing flammable hydrogen gas. Reacts with carboxylic acids, lower alcohols; chlorine, and ammonia (at 400C), forming explosive hydrogen gas.
Waste disposal
Lithium hydride may be mixed with sand, sprayed with butanol and then with water, neutralized and flushed to a sewer with water

Lithium hydride Upstream-Materialien And Downstream Produkte

Lithiumhydrid Anbieter Lieferant Produzent Hersteller Vertrieb Händler.

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