Lithium hydride

Lithium hydride - Names and Identifiers

Name	Lithium hydride
Synonyms	Lithiumhydride Hydride lithium Lithium hydride LITHIUM HYDRIDE , -30 MESH
CAS	7580-67-8
EINECS	231-484-3
InChI	InChI=1/Li.H/q+1;-1

Lithium hydride - Physico-chemical Properties

Molecular Formula	HLi
Molar Mass	7.95
Density	0.82g/mLat 25°C(lit.)
Melting Point	680°C(lit.)
Water Solubility	reacts
Solubility	Slightly soluble in dimethylformamide. Insoluble in acetone, benzene and toluene.
Appearance	powder
Color	White to gray
Exposure Limit	TLV-TWA 0.025 mg/m3 (ACGIH).
Merck	14,5533
PH	>7 (21g/l, H2O, 20℃)
Storage Condition	Store below +30°C.
Sensitive	Air & Moisture Sensitive
Physical and Chemical Properties	Density 0.82 melting point 680°C water-soluble reactions
Use	Used as desiccant, hydrogen generator and organic synthesis reducing agent

Lithium hydride - Risk and Safety

Risk Codes	R14 - Reacts violently with water R34 - Causes burns R25 - Toxic if swallowed R14/15 -
Safety Description	S16 - Keep away from sources of ignition. S26 - In case of contact with eyes, rinse immediately with plenty of water and seek medical advice. S27 - Take off immediately all contaminated clothing. S36/37/39 - Wear suitable protective clothing, gloves and eye/face protection. S7/8 - S45 - In case of accident or if you feel unwell, seek medical advice immediately (show the label whenever possible.) S25 - Avoid contact with eyes.
UN IDs	UN 1414 4.3/PG 1
WGK Germany	2
RTECS	OJ6300000
FLUKA BRAND F CODES	10
TSCA	Yes
HS Code	28500090
Hazard Class	4.3
Packing Group	I
Toxicity	LD50 orally in Rabbit: 78 mg/kg

Lithium hydride - Nature

Open Data Verified Data

A glass-like colorless transparent solid. The commercial product is usually a gray powder. The relative density was 0. 78. Melting point 688 °c. Boiling point> 700 °c (decomposition). It quickly turned gray in light. At room temperature in dry air does not decompose, and water decomposition reaction into lithium hydroxide and hydrogen. In
At room temperature and chlorine, oxygen, hydrogen chloride does not occur. Thermal decomposition may occur at high temperatures. The dissociation pressure was 0. 7mmHg at 500 °c and 850 mmHg at °c. Heat of fusion 22. 59kJ/mol; Soluble in ether, insoluble in benzene, toluene.

Last Update：2024-01-02 23:10:35

Lithium hydride - Preparation Method

Open Data Verified Data

in the drying oven, put lithium into a reaction tube made of stainless steel, cover and vacuum, and then enter hydrogen gas. After the hydrogen pressure is 1 atmosphere and the temperature is 725 ° C. For 15h, with continued hydrogen flow, cooling was carried out, and the reactants were taken out from the drying oven, filled in an ammonia-sealed bottle, and stored in the dark to obtain lithium hydride with a purity of up to 99. 8%.

Last Update：2022-01-01 11:07:11

Lithium hydride - Use

Open Data Verified Data

for military use as a source of hydrogen generation. Organic synthesis is used as a reducing agent.

Last Update：2022-01-01 11:07:10

Lithium hydride - Safety

Open Data Verified Data

packaged in glass bottles, each bottle having a net weight of 500g, and then concentrated in a wooden box, inner bedding or metal drum lined with polyethylene bag hermetically sealed, each net weight of 25kg. The package is marked with "moisture-proof" and "flammable. Hazard code: flammable item in wet condition. GB 4.3, class 43016D UN N0.1414; IMDG, code 4.3, page 1. Store in a cool, dry, ventilated warehouse. Stay away from heat sources and fire and avoid direct sunlight. With flammable materials, acids, oxidants and ethanol and other Isolation of the storage and transport. Protection against rain and sun during transport. It is not allowed to be handled in rainy days. Light load and light discharge during handling to prevent damage to the container. When there is a fire, only the metal cover can be used to quench the fire, or dry graphite powder, dry dolomite powder and cement can be used to quench the fire. Do not use water, carbon dioxide, foam, halogenated hydrocarbons (such as 1211 extinguishing agent) and so on. However, when the amount is very small, a large amount of water can be used to stop the rescue. Toxicity and protection: in the humid air can spontaneous combustion. Heat or contact with water or acids can occur exothermic reaction, can also cause combustion. It can react vigorously with the oxidant, and the dense dust is exposed to heat or oxidant, and the explosion is carried out. Dust has a strong irritating effect on the eyes, nose, skin and respiratory system. Lithium hydroxide generated in the presence of moisture or moisture is highly corrosive. Patients who inhale dust should be removed from the contaminated area and placed to rest and keep warm. The patient was immediately washed with water for more than 15min after she was not careful to splash into the eyes. Skin contact first rinse with water, then wash thoroughly with soap, if there is a burn timely diagnosis and treatment. The patient was immediately given mouthwash and water.

Last Update：2022-01-01 11:07:12

Lithium hydride - Reference Information

NIST chemical information	information provided by: webbook.nist.gov (external link)
EPA chemical substance information	information provided by: ofmpeb.epa.gov (external link)
The only stable hydride	lithium hydride is the hydride of lithium, belonging to the alkali metal hydride, lithium hydride has a cubic structure, more stable than other group 1 metal hydrides, lithium hydride is the only stable hydride in alkali metal hydrides, glass-like colorless transparent cubic crystal or translucent solid, ionic crystal, with rock salt type structure, lattice constant = 0.4085nm. The color rapidly darkened to gray under light but did not decompose in dry air at room temperature. At high temperature, it is decomposed into lithium and hydrogen, when the hydrogen is decompressed to 1.013 × 105Pa, the temperature is about 850, is higher than the melting point of 686 °c at 0.1MPa in hydrogen. Relative molecular mass 7.95. Relative density 0.78(25 degrees C). Melting point of 680 deg C, higher than 700 deg C decomposition. A solvent that is insoluble in benzene and toluene and does not react at all has not yet been found. Lithium hydride can react vigorously with water to produce lithium hydroxide and hydrogen: LiH H2O → LiOH H2. stable in dry air, with possibility of spontaneous combustion in wet air. In addition to the reaction with water at room temperature, it also reacts with ethanol, carbon tetrachloride and liquid ammonia; At high temperature, it can react with oxygen and chlorine to generate corresponding oxides and chlorides; it reacts with nitrogen to form amine compounds, imine compounds, and nitrides. It can react with aluminum chloride in ether to generate lithium aluminum hydride, which is a method for preparing lithium aluminum hydride: 4LiH AlCl3 → LiAlH4 3LiCl. crystal structure of lithium hydride lithium hydride is an important reducing agent for organic synthesis reaction and a raw material for producing lithium aluminum hydride. In addition, since lithium hydride itself is a strong and powerful reducing agent, it can be used for the reduction reaction of an organic substance, and can also be used as a condensing agent and a drying agent for a hydrogen generating agent. lithium hydride is absorbed by the human body, causing renal and neurological disorders. The maximum allowable concentration in the workplace is 0.025mg/m3.
lithium aluminum hydride	lithium aluminum hydride is prepared by the interaction of lithium hydride and anhydrous aluminum chloride in ether or alkali metal hydride with aluminum and hydrogen in hydrocarbon or ether species hydride. lithium aluminum hydride can be used as a strong reducing agent for many inorganic and organic compounds, and has a certain degree of space selective reaction to organic compounds. Capable of reducing: Silicon tetrachloride, tin organic halides, carbonyl compounds, carboxylic acids, nitriles and the like to obtain silane or disilane, stannane, hydroxy compounds, primary alcohols, primary amines and the like, respectively. It can undergo an exchange reaction with a metal halide or a non-metal halide. Reference: Ma Shichang, ed. Dictionary of chemical substances. Xi'an: Shaanxi Science and Technology Press. 1999. P. 536.
dangerous situation	(1) lithium hydride is slightly toxic, and dust can irritate the mucosa of eyes and upper respiratory tract. (2) lithium hydride is flammable, has a greater risk of combustion, in the humid air will spontaneous combustion. The formation of airborne mist. The dust mist may be exposed to an open flame, heat, or oxidant. The allowable concentration in air is 0.025mg/m3 in the United States.
incompatibility	is incompatible with oxidants, halogenated hydrocarbons, acids, and water.
invasive route	inhalation, ingestion, contact with eye and skin.
invasion site	respiratory system, skin, eye.
harmful effects and toxic symptoms	This product can burn eyes and skin. Oral can cause Nausea, muscle twitching, mental abnormalities, blurred vision and other symptoms.
first aid	if this chemical enters the eye, rinse immediately with water or eye wash; if the skin is contaminated, rinse with water; If inhaled in large quantities, immediately remove the site to fresh air and, if necessary, perform artificial respiration; If swallowed, give medical observation, take a large amount of water, quickly gastric lavage, and then symptomatic treatment.
Protection Measure	During operation, you should wear protective work clothes to prevent the possibility of skin contact with its content> 0.1mg/m3. Wear protective glasses to prevent contact with the eyes. If the work clothes are contaminated, take them off immediately. If there is> 0.5mg/m3 concentration of lithium hydride in the air, should be provided with safety signal indicator, flushing equipment and eye wash.
medical monitoring	before employment and regular medical examination, pay attention to the inspection of the invasion site.
toxicity	spontaneous combustion in humid air. Heat or contact with water or acids can occur exothermic reaction, can also cause combustion. It can react vigorously with the oxidant, and the dense dust is exposed to heat or oxidant, and the explosion is carried out. Dust has a strong irritating effect on the eyes, nose, skin and respiratory system. Lithium hydroxide generated in the presence of moisture or moisture is highly corrosive. Patients who inhale dust should be removed from the contaminated area and placed to rest and keep warm. The patient was immediately washed with water for more than 15 min after she was not careful to splash into the eyes. Skin contact first rinse with water, then wash thoroughly with soap, if there is a burn timely diagnosis and treatment. The patient was immediately given mouthwash and water.
determination method	determination in air: Sampling with filter material and analysis by atomic absorption spectrometry.
storage	can be contained in a metal can, protected by a box skin, or contained in a metal barrel to prevent mechanical damage. Store in a cool, dry, well-ventilated place, to prevent moisture. The building must be well ventilated and structurally free from the accumulation of gas.
transportation requirements	lithium hydride is a Class I water burning article. Crisis#: 51007. Containers shall be marked with a "great risk of flammable solids and moisture" when transported.
fire extinguishing measures	Water, CO2, dry powder extinguishing agent and halogen extinguishing agent (such as CCl4) are prohibited. A small can can can be turned back on the fire to asphyxiate the fire. If a fire occurs in the barrel, the barrel can be covered. Dry graphite or marble can be used to asphyxiate the fire.
recommended waste treatment method	lithium hydride is mixed with sand, sprayed with butanol, then sprayed with water, neutralized, water was flushed into the sewer.
Use	for military use as a source of hydrogen generation. Organic synthesis is used as a reducing agent. used as desiccant, hydrogen generator and reducing agent in organic synthesis lithium hydride used as condensing agent, reducing agent, alkylating agent, drying agent in organic synthesis, at the same time, it is also a good hydrogen storage material In organic synthesis, used as condensing agent, reducing agent, alkylating agent, Clemson's reagent, can also be used as desiccant used as desiccant, organic synthesis of condensation agent, nuclear protective materials and reducing agents, such as
production method	in the drying oven, put lithium into the reaction tube made of stainless steel, cover and vacuum, and then enter the hydrogen gas, after the hydrogen gas pressure is one atmosphere pressure and the temperature is 725 ° C. For 15h, the reaction is cooled while the hydrogen gas is continued, and the reactant is taken out from the drying oven and put into a nitrogen-sealed bottle, stored in the dark, the highest purity of lithium hydride was 99.8%. Its 2 Li H2 → 2LiH
category	water burning articles
toxicity grade	high toxicity
Acute toxicity	oral-rat LD50: 77.5 mg/kg; Inhalation-rat LCL0: 10 mg/m3/4 h
stimulation data	eye-rabbit 5 mg/m3
explosive hazard characteristics	explosion of hydrogen emitted by water and moist air
flammability hazard characteristics	when water or moist air emits hydrogen
storage and transportation characteristics	The warehouse is ventilated and dried at low temperature; It is stored separately from oxidant, halogen and strong acid
extinguishing agent	dry powder, dry powder
Occupational Standard	TWA 0.025 mg/m3; Tel 0.075 mg/m3
toxic substance data	information provided by: pubchem.ncbi.nlm.nih.gov (external link)
immediate life-threatening and health concentration	0.5 mg/m3